Online Dictionary of Invertebrate Zoology Parasitology, Harold W

Home , Gyros (moth), Mentum, Phaos, Phiala, Phyle (moth), Plait (gastropod)

University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln

Armand R. Maggenti Online Dictionary of Invertebrate Zoology Parasitology, Harold W. Manter Laboratory of

September 2005

Online Dictionary of Invertebrate Zoology: P

Mary Ann Basinger Maggenti University of California-Davis

Armand R. Maggenti University of California, Davis

Scott Gardner [email protected]

Follow this and additional works at: https://digitalcommons.unl.edu/onlinedictinvertzoology

Part of the Zoology Commons

Maggenti, Mary Ann Basinger; Maggenti, Armand R.; and Gardner, Scott, "Online Dictionary of Invertebrate Zoology: P" (2005). Armand R. Maggenti Online Dictionary of Invertebrate Zoology. 9. https://digitalcommons.unl.edu/onlinedictinvertzoology/9

This Article is brought to you for free and open access by the Parasitology, Harold W. Manter Laboratory of at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Armand R. Maggenti Online Dictionary of Invertebrate Zoology by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. 651 On line Di ctio nar palaeartic region A zoogyeoofgraphical region encompassing Inv Europe and northern Asia incleurdteing Japan, the Middle and P bra Near East and areas along the southte rZn coast of the Medi- ool terranean Sea. ogy palatal a. [L. palatum, palate] 1. Belonging to the outer lip. 2. P 1 In Mendel's laws, the first parental generation; parents of a (MOLL: Gastropoda) Referring to folds and lamellae of the given individual of the F 1 generation. shell. pachynema n. [Gr. pachys, thick; nema, thread] Thickened, palatal setae (ARTHRO: Insecta) In Culicidae, four small pe- paired chromosomes of meiosis prophase I, third stage; glike cibarial setae located on the anterior hard palate. sometimes used as a synonym of pachytene. palate n. [L. palatum, roof of the mouth] 1. (ARTHRO: Diplo- pachyodont a. [Gr. pachys, thick; odous, tooth] (MOLL: Bival- poda) The endostome. 2. (ARTHRO: Insecta) The epiphar- via) With heavy, blunt, amorphous teeth. ynx. 3. (BRYO: Gymnolaemata) In Cheilostomata, the mandibular part of the avicularium. pachytene n. [Gr. pachys, thick; tainia, ribbon] A prophase I stage in meiosis in which the chromosomes are thickened palatum n. [L. palatum, roof of the mouth] (ARTHRO: Insecta) and paired and crossing over occurs. see pachynema. In Culicidae, the oral surfaces of the labrum and clypeus; divided into labropalatum and clypeopalatum. pad n. [origin uncertain] (MOLL: Bivalvia) In oysters, a thin aragonite layer on which the adductor muscle is inserted. palea n.; pl. paleae [L. palea, chaff] (ANN: Polychaeta) A broad flattened seta used for burrowing. paedogenesis n. [Gr. pais, child; gennaein, to produce] 1. (ARTHRO: Insecta) Parthenogenetic reproduction by insect paleospecies n. [Gr. palaios, ancient; L. species, form] Fossils larvae structurally unable to copulate. 2. Progenesis. see that are placed in a species because of similar appearance. neoteny. paleotropical n. [Gr. palaios, ancient; tropos, turn] Of or per- paedomorphosis n. [Gr. pais, child; morphosis, shaping] taining to the tropical or subtropical regions of the old Evolutionary change in which ancestrally immature struc- world. tures are retained. palette n. [L. pala, spade] (ARTHRO: Insecta) In males of Col- paedoparthenogenesis see paedogenesis eoptera, the modified cupule-bearing tarsus of an anterior leg. pagina n. [L. pagina, leaf] (ARTHRO: Insecta) The surface of a wing; inferior= lower surface; superior= upper surface. pali n.pl.; sing. palus [L. palus, stake] 1. (ARTHRO: Insecta) A straight or pointed spine. 2. (CNID: Anthozoa) Small ridges pagiopodous a. [Gr. pagios, solid; pous, foot] (ARTHRO: In- between the columella and septa of scleractinian corals. secta) In aquatic Hemiptera, refers to the posterior coxae having the articulation in the form of a hinge joint. see tro- palidium n.; pl. -ia [L. dim palus, stake] (ARTHRO: Insecta) In chalopodous. scarabaeoid larvae, a paired group of spines placed either before the anus or from the ends of the anal slit; the pali paired see didymous are recumbent and may occur in one to many rows. pairing a. [L. par, equal] Chromosome pairing, highly specific paliform lobe (CNID) A palus detached from the inner edge of association (side by side) of homologous chromosomes. a septum. pala n.; pl. palae [L. pala, shovel] (ARTHRO: Insecta) In corixid palingenesis n. [Gr. palin, back; genesis, descent] 1. Charac- Hemiptera, the tarsus modified as a hair-fringed scoop for teristics of an individual that repeats the phylogenetic de- particle feeding. 652 653 Maggenti and Gardner On line Di ctio nar velopment of its taxon. 2. The regeneration or restoration next to the pallial line. y of Inv of a lost part. 3. Abrupt metamorphosis. see cenogenesis, erte pallial retractor muscles Muscles tbhraat withdraw the edge of recapitulation theory. te Z the pallium into the shell. ool ogy palintrope n. [Gr. palin, back; tropos, turn] (BRACHIO) The re- pallial sinus 1. (BRACHIO) see mantle canal. 2. (MOLL: Bival- curved part of the ventral valve that fills the gap between via) A notch or recess in the pallial line. the beak and hinge line in the dorsal valve of some shells. palliobranchial fusion (MOLL: Bivalvia) Having the ctenidia palisade n. [L. palus, stake] (ARTHRO: Insecta) The clear re- outer tips fused to the mantle margin. gion formed around the rhabdom in a light-adapted eucone apposition eye when exposed to darkness. palliolum n. [L. dim. pallium, mantle] (ARTHRO: Insecta) In Siphonaptera, the outer (external) wall of the aedeagus. pallets n.pl. [L. dim. pala, spade] (MOLL: Bivalvia) Two variously shaped calcareous structures at the siphonal tip of palliopedal a. [L. pallium, mantle; pedis, foot] (MOLL) Pertains some woodboring forms; abrading tools. to the mantle and foot. pallial a. [L. pallium, mantle] (MOLL) Of or pertaining to the pallioperitoneal a. [L. pallium, mantle; Gr. periteinein, to mantle. stretch around] (MOLL) Pertaining to a complex that includes heart, renal organs, gonads and ctenidia. pallial artery (MOLL) An artery that supplies blood to the mantle. pallium n. [L. pallium, mantle] 1. The mantle of a bivalve Mol- lusca or a Brachiopoda. 2. (ARTHRO: Insecta) In certain pallial chamber or cavity (MOLL) The mantle cavity. Orthoptera (Caelifera), a membrane from the free margin pallial complex (MOLL) All of the organs of the mantle cavity of the subgenital plate covering the retracted phallus. combined (ctenidia, osphradia, anus, renal and genital palm see manus openings and glands). palmaria, palmars see tertibrach pallial curtain (MOLL: Bivalvia) The inner fold of the mantle edge of oysters, with a row of tentacles, supplied with palmate a. [L. palma, hand] 1. Digitate; parts arising from a muscles and blood sinuses. common center; flat and wide with projections like fingers, as certain corals. 2. (PORIF) Megasclere with chela having pallial duct (MOLL: Gastropoda) Region of the genital duct that sheetlike or winglike elaborations. has undergone elaboration or differentiation to provide for sperm storage and egg membrane formation. Palmen's organ (ARTHRO: Insecta) In Ephemeroptera, a cuticular nodule at the junction of four tracheae mid-dorsally pallial groove (MOLL: Polyplacophora) Ventral groove marking behind the eyes of the adult and larva; may function as a the separation between the foot and mantle. statocyst. pallial line (MOLL: Bivalvia) A fine, single-lined impression near palmula see pulvillus the periphery of each valve, produced by the edge of the mantle and indicating the internal line of attachment of the palp see palpus/palp mantle to the shell. palpation n. [L. palpus, feeler] (ARTHRO: Insecta) The act of pallial markings see vascular markings touching with labial or maxillary palps; serves as sensory probe or tactile signal to another insect. pallial nerves (MOLL) The pair of large dorsal nerves that in- nervate the mantle. palp foramen (ARTHRO: Crustacea) A small opening in the mandibular body. pallial region (MOLL: Bivalvia) Marginal region inside the shell palpifer n. [L. palpus, feeler; ferre, to carry] (ARTHRO: Insecta) 654 655 Maggenti and Gardner On line Di ctio nar A small lobe of the maxillary stipes to which the maxillary shape] Violin-shaped, oybolof ng at the two extremities and Inve palpus (palp) articulates. palpiferous a. see palpiger. contracted in the middle; pandurtreabte. rate palpiform a. [L. palpus, feeler; forma, shape] Shaped like a Pangaea n. [Gr. pan, all; gaia, earth] TheZtohoeory of an ancient log palpus. continent from which the present continenyts split off by palpiger n. [L. palpus, feeler; gerere, to carry] (ARTHRO: In- continental drift. secta) A lobe of the mentum of the labium that bears the pangamy see panmixia palpus. see palpifer. pangenesis n. [Gr. pan, all; genesis, origin] Darwin's pre- palpimacula n. [L. palpus, feeler; macula, spot] (ARTHRO: In- genetic hypothesis that somatic cells contain particles insecta) A sensory area on the labial palps of certain insects. fluenced by the environment that can move to the sex cells palpon see dactylozooid and influence heredity. palp proboscis/proboscide (MOLL: Bivalvia) A tentaculiform panmixia, panmixy n. [Gr. pan, all; mixis, a mixing] Random outgrowth on each outer labial palp that can extend into or interbreeding in a population; nonselective breeding. pan- on the substrate, where ciliated and glandular surfaces pick mictic a. up particles of food. panoistic ovariole Ovarioles that have no specialized nurse palpus/palp n.; pl. -pi [L. palpus, feeler] 1. (ANN) a. In Oli- cells and are of a primitive type; germ cells occurring with- gochaeta, one of a pair of elongate projections on the anal out interruption from one end to the other; panoistic egg segment. b. In Polychaeta, one of a pair of projections on tube. see meroistic. the sides of the head. 2. (ARTHRO: Chelicerata) a. In panthalassic a. [Gr. pan, all; thalassa, sea] Living in coastal Arachnida, the segmented appendage of the pedipalp, ex- and offshore waters. cluding coxa and endite; simple in female, a reproductive pantherine n. [L. pantherinus, panther-like] Spotted like a organ in males. b. In Acari, paired appendage of segment panther; similar in color to cervinus. 2, sensory in function; maybe up to 6 segments long. 3. (ARTHRO: Crustacea) In Cirripedia, oval, setose mandibular pantropical a. [Gr. pan, all; tropikos, turning] Denoting a endopod attached to the mandible or to the lateral margin thorough distribution in the tropics. of the labium. 4. (ARTHRO: Insecta) A telopodite of the panzootic a. [Gr. pan, all; zoon, animal] Referring to a wide- gnathal appendage. see maxillary palpus; labial spread disease of animals in a region; extensively epizo- palp/palpus. otic. paludicole a. [L. paludis, marsh; colere, to inhabit] Living in or papilioform a. [L. papilio, butterfly; forma, shape] Resembling frequenting marshes. a butterfly wing. palule n. [L. palus, stake] (CNID) A detached calcareous proc- papilla n., pl. -lae [L. papilla, nipple] 1. A nipplelike elevation, ess of corals. generally sensory in function. 2. (ANN: Hirudinoidea) In palus n.; pl. -li [L. palus, stake] 1. A stake-like structure. 2. leeches, a small to large protrusible sensory organ; (CNID) A verticle column along the inner edge of some metamerically arranged or scattered on the dorsal surface; septa. large papillae are called tubercules. 3. (ARTHRO: Crustacea) Small steep-sided prominences on the valve surface of Os- pandemic a. [Gr. pan, all; demos, people] A widespread epi- tracods. 4. (ARTHRO: Insecta) A minute soft projection, a demic. see eumenical, cosmopolitan, endemic. modified ligula of silk-spinning caterpillars. 5. (BRACHIO) panduriform a. [L. pandura, musical instrument; forma, Fine spines either solid or hollow on the inside of the shell; 656 657 Maggenti and Gardner On line Di ctio nar endospines. 6. (ECHINOD) In holothurians and ophiuroids, branchiocardiac and poystocfervical grooves and joining the Inve tube foot with sensory function. 7. (ECHI) Wart-like or postcervical in the lower part. rteb rate rounded tubercles on the surface of the body, maybe uni- paracardo n. [Gr. para, beside; L. cardo,Zhoionge] (ARTHRO: In- log form over the surface, and are often associated with glan- secta) A part of the basal sclerite of the cardyo of the max- dular cells. 8. (NEMATA) Pimple-like, simple sensory organs. illa. 9. (PLATY: Trematoda) An accessory adhesive organ bearing a retractile tip. 10. (SIPUN) Variously shaped elevations paraclypeus see mandibular plate of the surface of the trunk or introvert, usually associated paracme n. [Gr. parakme, decadence] The state of decline of a with glandular cells. group of organisms after the highest stage of development papillae anales (ARTHRO: Insecta) In female Lepidoptera, a (acme). see phylogerontic. pair of soft hairy lobes that flank the genital opening, paracopulatory organ (ARTHRO: Crustacea) In Isopoda, a sometimes modified and heavily sclerotized for the inser- specialized endopod of the pleopod utilized in copulation. tion of the eggs into plant tissue or into crevices. paracymbium n. [Gr. para, beside; kymbion, small boat] (AR- papilla genitalis (ARTHRO: Insecta) An outgrowth containing THRO: Chelicerata) In mature male Arachnida, a genital ap- the genital opening. pendage arising from the base of the cymbium in many papillary a. [L. papilla, nipple] A small nipple-like process; groups. minute nodes or bumps. parademe n. [Gr. para, beside; demas, body] A secondary papillary sac (MOLL) The left nephridium with two nephridia; apodeme arising from the edge of a sclerite. usually filled with projecting papillae. paraderm see pronymphal membrane papillate a. [L. papilla, nipple] Having surface elevations; paradigm n. [Gr. para, beside; deigma, example] An example, papillose; verrucose. pattern, or model. papilliform a. [L. papilla, nipple; forma, shape] Shaped like a paraerucism n. [Gr. para, beside; L. eruca, caterpillar] (AR- papilla. THRO: Insecta) Poisoning by hairless caterpillars with se- pappus n. [L. papus, down] Down. cretions by specialized glands. see lepidopterism. papula n.; pl. -lae [L. papula, pimple] 1. An isolated pimple or parafaciala n.pl. [Gr. para, beside; L. facies, face] (ARTHRO: small bump. 2. (ECHINOD: Asteroidea) Small finger-like Insecta) In Diptera, that portion of the face between the projections arising between the body wall spines, mainly on facial ridges and the eyes. see gena. the upper surface, that function in gas exchange and ex- parafrontals see genovertical plate cretion. paragaster see spongocoel papulous a. [L. papula, pimple] 1. Covered with small bumps paragastrula n. [Gr. para, beside; dim. gaster, stomach] (PO- or pimples. 2. (MOLL: Gastropoda) The operculum of some RIF) The gastrula formed by invagination of the flagellate Neritidae. cells of a amphiblastula. parabiosis n. [Gr. para, beside; biosis, manner of life] A form parageneon n. [Gr. para, beside; genos, descent] A little- of symbiosis where animals of two or more species live to- changing species that embraces some aberrant genotypes. gether amicably, but keep their broods separate. paragenetic a. [Gr. para, beside; genesis, descent] A chromo- parabranchial groove (ARTHRO: Crustacea) In Nephropidae, a some change that influences the expression of a gene but carapace groove below, behind and almost parallel to the not structure. 658 659 Maggenti and Gardner On line Di ctio nar paraglossa n.; pl. -ae [Gr. para, beside; glossa, tongue] (AR- next to an anal structurey.of Inv THRO: Insecta) One of a pair of terminal lingular lobes of erte paranal lobes see paraprocts bra the labium that arise distal to the postmentum. te Z ool paraneural muscle (SIPUN) Paired longitudoignyal muscles on paragnath n.; pl. -naths [Gr. para, beside; gnathos, jaw] 1. each side of the anterior portion of the nerve cord. Any part or structure that lies alongside a jaw or palp. 2. (ANN: Polychaeta) One of a pair of chitinous jaws. 3. (AR- paranota n.pl.; sing. paranotum [Gr. para, beside; notos, THRO: Crustacea) One of a pair of metastomal lobes. see back] (ARTHRO) Lateral extension of the tergite or pleuro- endognath. 4. (ARTHRO: Insecta) see superlinguae. tergite in Diplopoda and Insecta; paranotal expansions or lobes; generally accepted as the origin of wings. paragula n. [Gr. para, beside; gula, throat] (ARTHRO: Insecta) In some Coleoptera larvae, a paired, elongate sclerite on paranuclear body see centrosome either side of the gula. parapatric speciation Populations in geographical ranges that parahemizonid n. [Gr. para, beside; hemisys, half; L. zona, come in contact and genetic interchange is possible even girdle] (NEMATA: Secernentea) A hemizonion or other simi- without sympatry. see dichopatry. lar structure. parapet see collar paralabial areas (ARTHRO: Insecta) In aquatic Diptera larvae parapharynx see hypopharynx that possess a labial plate, a pair of areas lateral to the paraphyletic a. [Gr. para, beside; phyletes, tribesman] A mo- base of the labial plate. nophyletic group that does not contain all of the descen- paralectotype n. [Gr. para, beside; lektos, choose; typos, dants of the most recent common ancestor of that group. type] Any of the remaining syntypes after the selection of a paraphysis n.; pl. -yses [Gr. para, beside; physis, growth] lectotype. (ARTHRO: Insecta) In Coccoidea, the chitinized thickenings, paralimnion n. [Gr. para, beside; limne, pond] The shore area lateral ingrowths, or projections near the base of the py- of lakes. gidium. parallel mandibles (ARTHRO: Insecta) In Diptera larva, paral- parapleurolophocercous cercaria see pleurolophocercous lel mouth-hooks that move dorsoventrally. cercaria paramentum n. [Gr. para, beside; L. mentum, chin] (ARTHRO: parapleuron n.; pl. -ura [Gr. para, beside; pleuron, side] (AR- Insecta) In Coleoptera, paired, usually elongate, sclerite on THRO: Insecta) In Coleoptera, the undivided pleura of the either side of the mentum. thorax. paramera see parameres paraplicate folding (BRACHIO) A fold on either side of the dor- parameral lobes (ARTHRO: Insecta) In scarabaeoid beetles, sal sulcus on the brachial valve. lobe-shaped expansions at the distal end of a paramere. parapod, parapodium n.; pl. -dia [Gr. para, beside; pous, parameres n.pl. [Gr. para, beside; meros, part] 1. The right or foot] 1. (ANN: Polychaeta) Paired lateral, fleshy, paddle-like left halves of a bilaterally symmetrical animal. 2. (ARTHRO: appendages that bear one or more cirri; usually consisting Insecta) The outer pair of phallomeres that develop into of two main divisions, the notopodium and the neuro- male copulatory appendages; sometimes synonymized with podium. 2. (MOLL: Gastropoda) a. In Opisthobranchia, a lo- gonopophyses. 3. (ECHINOD) The perradius with half of in- belike extension of the creeping sole; a fin. b. In Apysiidae, terradius on either side. arising from the middle of the body. c. In Pteropoda, located anteriorly; functioning as oars. paranal a. [Gr. para, beside; L. anus, anus] To the side of or 660 661 Maggenti and Gardner On line Di ctio nar parapolar cells (MESO) Cells making up the ciliated somato- lives part or all of its lifey ionf or on the body of another living Inve derm behind the calotte. organism (host), obtaining nurttreibment from the latter, or rate paraproct n. [Gr. para, beside; proktos, anus] (ARTHRO) One exerting other harmful influence uponZoito. parasitic a. see log of a pair of plates, valves or lobes bordering the anus parasitoid. y lateroventrally in some Insecta, Chelicerata, and Diplo- parasitic castration Pertaining to the suppression or destruc- poda; synonyms vary with species and authors. para- tion of gonads by parasites; first used regarding Crustacea; proctal a. individual parasitic castration. see social parasitic cas- parapsidal see parapsis tration. parapsidal furrow (ARTHRO: Insecta) The longitudinal groove parasiticide a. [Gr. para, beside; sitos, food; L. caedare, to on each side of the mesonotum, lying near to the lateral kill] Distructive to parasites; parasiticidal. margin and separating the parapsides from the main parasitism n. [Gr. para, beside; sitos, food] A form of symbio- mesonotal plate. sis in which the symbiont benefits from the association and parapsidal grooves see parapsidal furrow causes detriment to the host. parapsidal suture (ARTHRO: Insecta) A longitudinal suture of parasitization n. [Gr. para, beside; sitos, food] The act of an the mesonotum separating the median area from the lat- organism taking food from the body of another organism eral area. (host) for the completion of its life cycle; usually detri- mental to the host. parapsis n.; pl. -sides [Gr. para, beside; hapsis, arch] (AR- THRO: Insecta) In Hymenoptera, side pieces of the scutel- parasitoid n. [Gr. para, beside; sitos, food; eidos, form] 1. lum separated from the median area by the parapsidal Any organism that is typically parasitic in its development, furrow or suture; scapula. but kills the host during or at the completion of its development. 2. Also used as an adjective to describe this mode paraptera see tegulae of life. 3. Alternately free-living and parasitic. parasagittal a. [Gr. para, beside; sagitta, arrow] A plane par- parasitology n. [Gr. para, beside; sitos, food; logos, dis- allel to the sagittal plane. course] The study of parasites. parascolus n. [Gr. para, beside; skolos, thorn] (ARTHRO: In- parasitophorous vacuole A vacuole within a host cell con- secta) In Coleoptera ladybird beetle larvae, a modification taining a parasite. of the scolus in which the projection is 2-3 times as long as wide. parasocial a. [Gr. para, beside; socius, companion] (ARTHRO: Insecta) Referring to forms that show one or more of the parascutal area see alar area following traits: cooperation in care of the young, repro- parasematic a. [Gr. para, beside; sema, sign] Pertaining to ductive division of labor, and overlapping of life stages that colors, structures or behavior that deceive preditors. see contribute to colony labor. see presocial. antiaposematic, sematic. parastipes see subgalea parasexual a. [Gr. para, beside; LL. sexualis, sexual] Refers to parasulcate folding (BRACHIO) With a sulcus on either side of all non-meiotic reproductive processes. the median fold of the brachial valve. parasigmoidal a. [Gr. para, beside; sigma, the 16th letter; parasymbiosis see neutralism eidos, form] Curved like a reversed letter "S." parasyndesis n. [Gr. para, beside; syndesis, binding together] parasite n. [Gr. para, beside; sitos, food] An organism that Parasynapsis; union of chromosomes side-to-side in the 662 663 Maggenti and Gardner On line Di ctio nar process of meiosis. see acrosyndesis. teeth. y of Inve paratenic host A host harboring a parasite that does not un- parecium n. [Gr. para, beside; ortiekbos, house] (ARTHRO: In- rate dergo further development and is generally of ecologic ad- secta) Air space surrounding a fungus Zgoaorden in the nest of log vantage in the disease cycle. Isoptera. y paratergite see laterotergite parenchyma n. [Gr. para, beside; NL. enchyma, type of cell parathyridium n.; pl. -dia [Gr. para, beside; dim. thyris, win- tissue] Undifferentiated tissue between organs in various dow] (BRACHIO) Deep indentation of both valves on either invertebrates. parenchymatous a. side of the beak; most pronounced in the dorsal valve. parenchymalia n.pl. [Gr. para, beside; NL. enchyma, type of paratomy n. [Gr. para, beside; tomos, cut] (ANN) Designating cell tissue] (PORIF: Hexactinellida) Spicules scattered the reproduction by fission with regeneration following pre- throughout the parenchyma, consisting of hexactines, di- paratory internal tissue reorganization. see architomy. actines, various hexasters and sometimes amphidisks. paratopotype n. [Gr. para, beside; topos, place; typos, type] parenchymula, parenchymella n. [Gr. para, beside; NL. en- A paratype recovered from the same locality as the holo- chyma, type of cell tissue] (PORIF) A solid, ciliated larva; a type. stereogastrula. paratroch see telotroch paria n.; pl. -ae [Gr. pareion, cheek] (ARTHRO: Insecta) In scarabaeoid larvae, the lateral paired region of the paratrophic a. [Gr. para, beside; trophe, food] Deriving food epipharynx from the clithrum, or epizygum and haptome- parasitically. rum to the dexiotorma or laetorma. paratype n. [Gr. para, beside; typos, shape] A specimen col- paries n.; pl. parietes [L. paries, wall] 1. A wall; any wall of a lected at the same time as the holotype and was so desig- part, cavity or hollow organ. 2. (ARTHRO: Crustacea) The nated or indicated by the original author. median part of every compartmental plate of sessile Cir- parauterine organ see paruterine organ ripedia. paraxial a. [Gr. para, beside; L. axis, axle] 1. To move parallel parietal a. [L. paries, wall] 1. (ARTHRO: Crustacea) Of or per- to the body axis. 2. par-axial (ARTHRO: Chelicerata) In spi- taining to paries. 2. (ARTHRO: Insecta) Referring to the dor- ders, pertaining to chelicerae with the paturon projecting sal sclerites of the cranium, between the frontal and oc- forward with the fangs moving in a downward direction. cipital areas; the adfrontal area or plate. 3. (MOLL: Gastro- see di-axial. poda) Pertaining to the inside wall of a univalve within the paraxial organs (ARTHRO: Chelicerata) Special gland pockets aperture, the broader upper part of the inner lip. that produce the spermatophores of male Scorpions. parietal callus (MOLL: Gastropoda) A thickening of the inner paraxon n. [Gr. para, beside; axon, axle] The collateral branch lip. of an axon. parietal fold (MOLL: Gastropoda) A spiral ridge on the parietal Parazoa n. [Gr. para, beside; zoon, animal] A subkingdom region projecting into the interior of the shell. containing Porifera; the sponges. parietal lip (MOLL: Gastropoda) A part of the inner lip on the parazoeal a. [Gr. para, beside; zoe, life] (ARTHRO: Crustacea) parietal region. In Bathynellacea, postembryological development (larval) parietal muscles (BRYO) Generally multiple, bilaterally paired phase, quite often completed in the egg. muscles that insert on the front wall or floor of the ascus; parcidentate a. [L. parcus, sparing; dens, tooth] Having few usually functioning in the hydrostatic system. 664 665 Maggenti and Gardner On line Di ctio nar parietal pore 1. (ARTHRO: Crustacea) see longitudinal tube. of a scolex extending they olef ngth of the bulbs at the tentacle Inve 2. (BRYO: Gymnolaemata) A hole in the distal wall of the base. rteb rate zooecium allowing communicating fibers between parsimony n. [L. parsimonia, frugality] ZEooconomizing in as- log polypides. sumption of reasoning. y parietal region (MOLL: Gastropoda) The basal surface of the pars incisiva see incisor process helical spiral shell located within and without the aperture. pars intercerebralis (ARTHRO: Insecta) A group of neurose- parietal ridge (MOLL: Gastropoda) The prominence on the pa- cretory cells near the midline on each side of the brain rietal lip near the adapical corner of the aperture. from which secretions promote the functioning of the pro- parietal septum see longitudinal septum thoracic glands, stimulate protein synthesis and are parietal tube see longitudinal tube thought to control water loss, oocyte development and activity. parietal wall see parietal region pars molaris see molar process parieto-basilar muscles (CNID: Anthozoa) Muscles on the column of Actinaria that run obliquely from the outer ends pars postbulbosa (PLATY: Cestoda) In Trypanorhyncha, a divi- of the mesenteries near the base on to the central parts of sion of the scolex from the hind margin of the tentacular the pedal disk; functioning to aid in fastening the animal to bulb to the posterior end of the scolex. the substratum. pars prostatica (PLATY: Cestoda) Dilation of the ejaculatory parivincular a. [L. par, equal; vinculum, bond] (MOLL: Bival- duct encircled by unicellular prostate cells. via) Having a ligament similar to a cylinder split on one pars stipitalis labii see prementum side, attached by several edges (nymphae), with one edge pars stridulans see strigil to each valve. see opisthodetic, amphidetic. pars vaginalis (PLATY: Cestoda) In Trypanorhyncha, a division parocciput n. [Gr. para, beside; L. occiput, back of head] (AR- of the scolex from the anterior end to the anterior end of THRO: Insecta) A thickening of the occiput for articulation of the tentacular bulbs. the cervical sclerites. parthenapogamy n. [Gr. parthenos, virgin; apo-, separate; paronychium n.; pl. -ia [Gr. para, beside; onykos, claw] (AR- gamein, to marry] Diploid parthenogenesis. THRO: Insecta) A bristle-like appendage on the pulvillus between the tarsal claw. parthenita n.; pl. -ae [Gr. parthenos, virgin] (PLATY: Trema- toda) The unisexual stage in an intermediate host. pars n.; pl. partes [L. pars, part] A part of an organ. parthenogenesis n. [Gr. parthenos, virgin; genesis, origin] pars ampullaris (ARTHRO: Crustacea) In Malacostraca (Hoplo- The development of an individual from an unfertilized egg. carida and Anaspidacea), a bottle-shaped structure at the parthenogenetic a. see arrenotoky, thelyotoky. entrance of the digestive glands into the pyloric chamber of the stomach. parthenogenone n. [Gr. parthenos, virgin; genesis, origin; on, being] A parthenogenetic organism; parthenogone. see pars basalis see cardo parthenote. pars bothrialis (PLATY: Cestoda) In Trypanorhyncha, a division parthenote n. [Gr. parthenos, virgin] A haploid organism pro- of the scolex from the anterior end to the hind margin of duced parthenogenetically. the bothridia. partial coverage see valve coverage pars bulbosa (PLATY: Cestoda) In Trypanorhyncha, a division particulate inheritance Mendel's theory that inheritance in an 666 667 Maggenti and Gardner On line Di ctio nar individual has distinct genetic factors from paternal and pathology n. [Gr. pathos,y osfuffering; logos, discourse] The Inv maternal forebearers. study of diseases. pathologicaerltea. bra te Z partite a. [L. partitus, divided] Divided; separated; parted. patocoles n.pl. [Gr. patos, bottom; L. coleroeo,lto dwell] Animals ogy parturition n. [L. parturire, to bring forth] The act of giving that spend part of their time dwelling in the cryptosphere birth. but emerge to hunt and mate. paruterine organ (PLATY: Cestoda) In Paruterininae, fibro- patronymic a. [Gr. pater, father; onyma, name] In nomen- muscular appendage that receives and stores the eggs, re- clature, a name based on that of a person. placing the uterus. patulous a. [L. patulus, standing open] Spreading; expanded; parva stage (ARTHRO: Crustacea) In Decapoda Caridea, the distended; having a wide aperture. first postlarval stage. paturon n. [Gr. patein, to trample on; oura, after part] (AR- parviconoid a. [L. parvus, small; conus, cone] Resembling a THRO: Chelicerata) In Acarina, a structure on the chelicera small cone. bearing numerous toothlike projections; rastellum. pastinum n. [L. pastinum, two pronged tool] (ARTHRO: Crusta- paucispiral a. [L. paucus, few; spira, coil] With relatively few cea) In male Ostracoda, chitinized skeletal rods (caudually whorls; oligogyral. fork-shaped) that support the entire copulatory complex. paunch see crop patabionts see cryptozoa Paurometabola n. [Gr. pauros, little; metabole, change] (AR- patagium n.; pl. patagia [L. patagium, border] (ARTHRO: In- THRO: Insecta) A division of the Heterometabola. secta) 1. In Lepidoptera, a pair of articulated, thin, lobe- paurometabolous a. [Gr. pauros, little; metabole, change] like erectile expansions (overlapping plates) of the protho- (ARTHRO: Insecta) Having slight metamorphosis, the young rax. 2. For Culicidae, see antepronotum. and adults living in the same habitat, and the adults have patella n.; pl. -lae [L. patella, small pan] 1. The knee cap. 2. wings. see holometabolous. (ARTHRO: Chelicerata) a. In Arachnida, a leg segment be- Pauropoda n. [Gr. pauros, little; pous, foot] (ARTHRO) Blind tween the femur and tibia (the 4th segment). b. For Acari, myriapoda, having 9-11 leg-bearing trunk segments, be- see genu. patelliform a. longing in the phylum Arthropoda. patellar a. [L. patella, small pan] 1. Pertaining to the patella; a paurostyle n. [Gr. pauros, little; stylos, pillar] (BRYO: Stenol- small pan; a kneepan. 2. (MOLL: Cephalopoda) The saucer- aemata) A type of stylet of cryptostomates with an irregu- shape, typical of Patellacea. lar rod of nonlaminated material, with laminae weakly de- patent a. [L. patens, lying open] Open; diverging; expanded; flected toward the zoarial surface; usually smaller than spreading apart. see prepatent period. acanthostyles. pathogen n. [Gr. pathos, suffering; gennaein, to produce] 1. A Pavan's gland (ARTHRO: Insecta) A gland of many Dolicho- disease causing microorganism. 2. A parasite causing in- derine, associated with a conspicuous palisade epithelium jury to a host. on the 7th sternum that functions to secrete a pheromone trail; a sternal gland. pathogenesis n. [Gr. pathos, suffering; genesis, origin] The origination and development of disease. pathogenic a. Pawlowsky's glands (ARTHRO: Insecta) In Siphunculata, a pair of glands that open into the stylet sac and possibly pathognomonic a. [Gr. pathos, suffering; gnom, sign] A diag- function to lubricate the stylets. nostic symptom by which a disease may be recognized. paxilla n.; pl. -lae [L. paxillus, a peg] 1. A small spine or peg. 668 669 Maggenti and Gardner On line Di ctio nar 2. (ECHINOD: Asteroidea) A raised ossicle on the aboral allows extension of the fyooft. Inv surface, crowned with small movable spines or granules. erte pedal glands (ROTIF: Bdelloidea) Glabnrdas in the retractile foot, paxilliform a. te Z opening through the toes, that secreteoaoln adhesive to at- ogy Pearman's organ (ARTHRO: Insecta) A rugose area adjacent tach the animal to the substrate while feeding. to a membranous tympanum on the inner side of the hind pedal groove (MOLL: Solenogastres) A longitudinal fold or folds coxae of Psocids, thought to be a stridulatory organ. with ciliated and secretory cells in the median ventral posi- pecilonymy see poecilonymy tion. pecking order see hierarchy pedalium n.; pl. -alia [Gr. pedalion, rudder] (CNID) Bladelike pecten n.; pl. pectines [L. pecten, comb] 1. Any comb- or expansions at each corner of the umbrella that bear a mo- rake-like structure. 2. (ARTHRO: Chelicerata) In Scorpiones, tile and contractile hollow tentacle or group of tentacles. one of a pair of appendages on the somite immediately be- pedal levator muscle see pedal retractor muscle hind the genital somite. 3. (ARTHRO: Insecta) a. In Culici- pedal lobe (ARTHRO: Insecta) A fleshy, bump-like, non-seg- dae, a Culicinae larvae, bearing a comblike row of spicules mented rudimentary leg of a larva. on the basal part of the siphon; in Anophelinae and Dixidae larvae, borne on the posterior margin of the pecten plate. pedal pit (MOLL: Solengastres) A ciliated pit containing secre- b. In Apidae, the pollen rake. c. In genitalia, distally point- tory cells at the anterior end of the pedal groove. ing rows of comblike teeth lining the articular membrane of pedal protractor muscle (MOLL: Bivalvia) The muscle that the gonopophyses. d. In Diaspidinae, see gland spines. extends the foot. pectina n.; pl. -ae [L. pecten, comb] (ARTHRO: Insecta) One of pedal retractor muscle (MOLL: Bivalvia) The muscle attached the broad fringed plates on the pygidium of coccids. to the shell that withdraws the foot; pedal levator muscle. pectinate a. [L. pecten, comb] 1. Having branches or proc- pedal stridulating organ (ARTHRO: Insecta) In male Hemip- esses like a comb. 2. Of claws; having teeth. terous Corixidae, the spinose area on the inside of each pectinate chaeta (ANN: Oligochaeta) Crochet seta with two front femur when drawn over the edge of the clypeus. lateral teeth with several fine teeth between. pedamina n.pl.; sing. -um [L. pes, foot; mina, projecting pectinations n.pl. [L. pecten, comb] (MOLL: Polyplacorphora) point] (ARTHRO: Insecta) In Lepidoptera, the aborted fore- Small sharp teeth on the outer edges of the insertion legs of a nymph. plates. peddler n. [ME. pedlere, fr. ped, basket] (ARTHRO: Insecta) A pectunculate a. [L. pecten, comb; -unculus, little] Having a larva of Cassidinae Coleoptera, having a forked caudal row of minute appendages; pectunculoid. process supporting excrement and exuviae. pectus n. [L. pectus, breast] (ARTHRO) A sclerite composed of pedicel n. [L. pediculus, little foot] 1. Any small or short stalk pleuron fused with the sternum. or stem supporting an organ or other structure. 2. (AR- THRO: Chelicerata) In Arachnida, the attenuated first ab- pedal a. [L. pedis, foot] Pertaining to a footlike appendage. dominal segment, joining the abdomen to the cephalotho- pedal disc (CNID: Anthozoa) In Actinaria, the base or foot. rax. 3. (ARTHRO: Insecta) a. The second segment of the pedal elevator muscle (MOLL: Bivalvia) Muscle fibers attached antenna. b. An ovariole stalk, or short duct connecting the in the umbonal cavity that raise the foot. egg tubes with the later oviduct. c. In Formicidae, the stem of the abdomen, between the thorax and gaster. pedal gape (MOLL: Bivalvia) Opening between shell valves that pedicellariae n.pl. [L. pediculus, little foot] (ECHINOD) In 670 671 Maggenti and Gardner On line Di ctio nar Echinoidea and Asteroidea, stalked pincer-like structures, ventral valve. y of Inv usually armed with teeth, used for removal of foreign parti- erte pedigerous a. [L. pes, foot; gerare, btroa carry] Bearing footlike cles and prevention of larvae of sessile organisms from te Z appendages. ool settling on the animal; sessile pedicellariae are composed ogy of two or more short, movable spines on the same or adja- pedipalp, pedipalpus n.; pl. -pi [L. pes, foot; palpare, to cent ossicles. touch] (ARTHRO: Chelicerata) The second pair of cephalo- thoracic appendages, variously modified as a pincerlike pedicellate a. [L. pediculus, little foot] Supported by a pedicel claw, or simple leg-like in different groups. or petiole. pedisulcus n. [L. pes, foot; sulcus, furrow] (ARTHRO: Insecta) pedicellus spines (ARTHRO: Insecta) In Hymenoptera and In Diptera, an indentation near the base of the second hind Diptera, sensory spines at the bases of the antennae that tarsal segment of some Simuliidae. play a role in the perception of gravity and possibly current stimuli. pedium n.; pl. -dia [Gr. pedion, open plain] (ARTHRO: Insecta) In scarabaeoid larvae, the central part of the epipharynx, pedicle n. [L. pediculus, little foot] (BRACHIO) A variously de- bare and soft-skinned, between the haptomerum and hap- veloped, tough flexible stalk protruding from the bivalve tolachus; crossed on the left side by the epitorma. shell; functioning as a tether, a pivot around which the shell may be moved, or as a locomotory organ. pedofossae n.pl. [L. pes, foot; fossa, ditch] (ARTHRO: Cheli- cerata) In Acari, concavities in the podosoma into which pedicle collar (BRACHIO) The two deltidial plates curved legs II, III and IV can be tucked. around the pedicle base, may or may not be fused. pedogenesis see paedogenesis pedicle foramen (BRACHIO) Ring-like perforation of a shell through which the pedicle passes. pedothecae n.pl. [Gr. pedon, ground; theke, case] (ARTHRO: Insecta) In Diptera pupae, the adhering sheaths of the pedicle groove (BRACHIO) When present, subtriangular groove legs. dividing the ventral pseudointerarea medially and allowing passage for pedicle. peduncle n. [L. pedunculus, small foot] A stem, stalk or petiole supporting an organ or other structure. pedunculate a. pedicle muscles (BRACHIO) 1. In Articulata, adjuster muscles external to the pedicle and longitudinal fibrils in the con- pedunculate bodies see corpora pedunculata nective tissue of the pedicle. 2. In Inarticulata, muscles in pedunculate papillae (NEMATA) A modified, stalked, genital the wall and coelom of the pedicle. papillae of males. pedicle plate (BRACHIO) A tongue-like shell deposit inside the pelagic a. [Gr. pelagos, open sea] Pertaining to the open sea; dorsal edge of the labiate foramen. ocean-dwelling. pedicle sheath (BRACHIO) A tube projecting posteroventrally pelagosphera n. [Gr. pelagos, open sea; sphaira, ball] (SIPUN) from the ventral umbo; probably enclosing the pedicle in The second larval stage, characterized by a terminal organ the young stages of shell development with a supra-apical for temporary attachment to the substratum, a band of pedicle foramen. metatrochal swimming cilia, and a retractable anterior pedicle tube (BRACHIO) A tube of secondary shell enclosing body. the proximal part of the pedicle. Pelecypoda see Bivalvia pedicle valve (BRACHIO) The valve from which the pedicle pellicle n. [L. pellis, skin] A thin skin, film or layer. usually emerges, generally larger than the brachial valve; pellions see rosettes 672 673 Maggenti and Gardner On line Di ctio nar pellucid a. [L. per, through; lucere, to shine] Transparent or penicilliform a. [L. peniciylluomf , painter's brush] Having the Inve clear; not colored. form of a brush or pencil; tippedrtewbith fine hairs or fibers. rate pelma n. [Gr. pelma, sole] (ECHINOD: Crinoidea) The stalk and penicillum, penicillus n.; pl. -li [L. Zpoeonicillum, painter's log holdfast beneath the crown. brush] A pencil or brush of setae or hair. y peloderan a. [Gr. pella, cup, bowl; deros, skin] (NEMATA) Per- peniferum n. [L. penis, male copulatory organ; ferum, bear] taining to caudal alae that meet at the male tail tip. see (ARTHRO: Crustacea) In Ostracoda, the varied, sclerotized leptoderan. male copulatory apparatus that bears the penis and hinge pelopsiform a. [Gr. pelops, genus of orbatid mites; L. forma, on which the apparatus may turn around the zygum. shape] (ARTHRO: Chelicerata) In Acari, having the form of penis n.; pl. -es [L. penis, male copulatory organ] A male the genus Pelops. copulatory organ or paired organs for conveying sperm to peltate a. [Gr. pelte, shield] Shield-shaped; escutcheon. pelta- the genital tract of a female. see phallus, aedeagus. tion n. penis funnel see anellus peltidium n. [Gr. pelte, shield] (ARTHRO: Chelicerata) In acari, penis valves (ARTHRO: Insecta) In Hymenoptera, genital the prodorsal shield. see schizopeltid. clasper organs. peltogonopod n. [Gr. pelte, shield; gone, seed; pous, foot] pennaceous a. [L. penna, feather] Resembling a feather, as a (ARTHRO: Diplopoda) Accessory gonopods; often plate-like marking; penniform. shields of the gonopods. pentacrinoid a. [Gr. pente, five; krinon, lily] (ECHINOD: Cri- pen n. [L. penna, feather] (MOLL: Cephalopoda) In Teuthoidea, noidea) A larval stage following the cystidean stage that an internal shell that may be slender, thin, delicate, horny attaches to the substrate or adult crinoid and develops a or lanceolate. see gladius. crown of arms and cirri. pencil n. [L. dim. penis, tail] 1. A brush of hair or bristles. see pentactula larva (ECHINOD: Holothuroidea) A young larva with brushes. 2. (ARTHRO: Insecta) In Diptera, sensory hair on 5 primary tentacles and one or two podia that eventually the distal part of the antenna. settle to the bottom and assume the adult mode of exis- pendent a. [L. pendere, to hang] Hanging; suspended from tence. above. pendulous a. pentaglossate a. [Gr. pente, five; glossa, tongue] (MOLL) penellipse n. [L. paene, almost; Gr. elleipsis, leaving out] (AR- Having no central tooth and teeth of the same shape that THRO: Insecta) In larvae, a series of crochets usually more increase in size toward the edge of the radula. than a semicircle and less than a complete circle. see lat- pentagonal a. [Gr. pente, five; gonia, angle] Five-sided; hav- eral penellipse, mesal penellipse. ing 5 angles. penetrant see stenotele pentamerous a. [Gr. pente, five; meros, part] Composed of 5 penial chaeta/seta (ANN: Oligochaeta) One of the extra seta similar parts; having 5-jointed tarsi. near the male pore that facilitate the passage of sperm pentaradiate a. [Gr. pente, five; L. radius, ray] Arranged in 5 during copulation; usually long, sculptured, and in paired rays. bundles. pentazonian segment (ARTHRO: Diplopoda) A segment penicilla n.; pl. -ae [L. penicillum, painter's brush] (ARTHRO: formed of 5 separate sclerites; the tergum, 2 lateral pleu- Crustacea) In certain Anaspidacea, dentate setae on the rites and 2 sternites. mandible. 674 675 Maggenti and Gardner On line Di ctio nar penultimate a. [L. paene, almost; ultimus, last] Next to the perianal a. [Gr. peri, arouyndo;f L. anus] Situated or occurring Inv last; the whorl preceding the last. around the anus. erte bra te Z peptonephridia n.pl. [Gr. pepton, digested; nephros, kidney] periaxial a. [Gr. peri, around; L. axis] To suororlound an axis. ogy (ANN: Oligochaeta) Organs opening into the buccal cavity of peribuccal a. [Gr. peri, around; L. bucca, mouth cavity] Encir- pharynx (supposedly modified nephridia). cling the buccal cavity. peraeon see pereon pericardial cavity see dorsal sinus peraeonite see pereonite pericardial cells (ARTHRO: Insecta) Nephrocytes present on peraeopod see pereopod the surface of the heart, or lying on the pericardial septum percurrent a. [L. per, through; currere, to run] Extending or the alary muscles. through the entire length; continuous. pericardial gland 1. (ARTHRO: Insecta) see prothoracic gland. percutaneous a. [L. per, through; cutis, skin] Penetration 2. (MOLL: Gastropoda) Marginal cells of the pericardium in through the skin. Prosobranchia; filled with yellow-green granules. peregrine see allochthonous, anthropochorous pericardial sinus see dorsal sinus pereionite see pereonite pericardium n. [Gr. peri, around; kardia, heart] The cavity enclosing the heart as well as membranes lining the cavity pereiopod see pereopod and covering the heart. pericardial a. pereon, pereion, peraeon n. [Gr. peraioun, to convey] 1. pericaryon see perikaryon (ARTHRO: Crustacea) A thoracic region of Isopoda; anterior portion of the trunk bearing thoracopods, except for maxil- pericentric inversion An inversion that includes the centro- lipedal somites and appendages. 2. pereion (ARTHRO: In- mere. secta) see prothorax. pereonal a. perichaetine a. [Gr. peri, around; chaite, mane] (ANN: Oli- pereonite n. [Gr. peraioun, to convey; -ites, joined to] (AR- gochaeta) Referring to setal location, when there is more THRO: Crustacea) Somite of the pereon; peraeonite, than 8 per segment, encircling a segment; perichaetal con- pereionite. dition. pereopod, peraeopod, pereiopod n. [Gr. peraioun, to con- perideltidium n.; pl. -ia [Gr. peri, around; dim. delta, ] vey; pous, foot] (ARTHRO: Crustacea) Thoracic appendage (BRACHIO) One of a pair of raised triangular areas on either used in locomotion and for seizing and handling food; am- side of the pseudodeltidium with both striae and growth bulatory leg; walking leg; trunk legs. lines. perideltidial a. perfect mesentaries (CNID: Anthozoa) Mesenteries spanning periderm n. [Gr. peri, around; derma, skin] (CNID: Hydrozoa) the gastrovascular space and inserting on the body wall A hydroid perisarc. and actino-pharynx. see imperfect mesentaries. perienteric a. [Gr. peri, around; enteron, gut] Surrounding the perfoliate a. [L. per, through; folium, leaf] With terminal joints alimentary tract. leaflike and surrounding the stalk connecting them. periflagellar membrane (PORIF) A membrane between choa- perforate a. [L. per, through; forare, to bore] Pierced; having nocyte collar tentacles and the apical flagellum. pores or small openings. perigastric a. [Gr. peri, around; gaster, stomach] Surrounding pergameneous a. [L. pergamena, parchment] Of the nature the visera. or texture of parchment. perignathic girdle (ECHINOD: Echinoidea) A calcareous ridge 676 677 Maggenti and Gardner On line Di ctio nar on the inner side of the peristomal edge of the test that gression from a copulatyoroyf stage to a noncopulatory stage Inv serves as the attachment for the muscles of the mastica- in consecutive molts; subsequeerntet molting leads to a copu- bra tory apparatus. latory stage again. te Z ool ogy perihemal a. [Gr. peri, around; haima, blood] (ECHINOD) Vari- periopticon see lamina ous tubular coelomic sinuses that form channels of the he- perioral disc see labial disc mal system. periostracal glands (MOLL: Bivalvia) Glands of the mantle perikaryon, pericaryon n.; pl. -karya [Gr. peri, around; edge that secrete the base layer of the periostracum. karyon, nucleus] The portion of the cell that contains the nucleus. periostracal groove (MOLL: Bivalvia) The groove between the tentacular fold and the shell fold that houses the periostra- perilemma n.; pl. -ae [Gr. peri, around; lemma, bark] (AR- cal glands. THRO) A layer of glial cells beneath the fibrous neurilemma glanglia. periostracum n. [Gr. peri, around; ostrakon, shell] A thin skin or horny covering on the exterior of the shells of most perilymph n. [Gr. peri, around; L. lympha, water] (MOLL: Mollusca and Brachiopoda. periostracal a. Cephalopoda) In Octopodidae, the liquid that fills the outer sac of the statocyst. periparturient period That period before, during and after giving birth. perimetrical attachment organ (BRYO: Stenolaemata) Col- larlike membrane attached to the tentacle sheath and to periphallic organs (ARTHRO: Insecta) Genital processes on the both the outer end of the membranous sac and skeletal posterior ventral surface of segment 9. body wall. peripharyngeal ganglion (BRYO) Prolongation of the cerebral perinaeum see perineum ganglion around the oral opening. perinductura n. [Gr. peri, around; L. inductura, a covering] peripheral a. [Gr. peri, around; pherein, to carry] To or to- (MOLL: Gastropoda) A continuous outer shell layer formed ward the surface; distant from the center. by the edge of the mantle reflected back over the outer lip. peripheral nerve net (NEMATA: Adenophorea) A subcuticular perineum n. [Gr. peri, around; enein, to empty out] (ARTHRO: neural meshwork that connects the setae and papillae on Insecta) The area between the posterior of the anus and the whole body surface of some marine forms. the anterior part of the external genitalia, especially in fe- peripheral nervous system Contains all sensory cell bodies males. perineal a. (exceptions rare), plus local plexuses in the body wall or perineural a. [Gr. peri, around; neuron, nerve] Surrounding a viscera, local ganglia of either sensory or motor-and-inter- nerve or nerve cord. nuncial composition, plus the pheripheral axons making up the nerves. perineurium n. [Gr. peri, around; neuron, nerve] (ARTHRO: Insecta) A layer of cells beneath the neural lamella in the periplasm n. [Gr. peri, around; plassein, to mold] (ARTHRO: nerve sheath. Insecta) A bounding layer formed by cytoplasm in the egg that lies just beneath the vitelline membrane and com- perinotum see girdle pletely surrounds the egg. periodicity a. [Gr. peri, around; hodos, way] Functions that peripneustic a. [Gr. peri, around; pneustikos, of breathing] occur at regular intervals or times; rhythm. (ARTHRO: Insecta) Having 9 pairs of functional spiracles; periodomorphosis n. [Gr. peri, around; hodos, way; morpho- usually a prothoracic pair and 8 abdominal pairs. see sis, shaping] (ARTHRO: Diplopoda) In some male Julida, re- polypneustic. 678 679 Maggenti and Gardner On line Di ctio nar peripodial cavities (ARTHRO: Insecta) A cavity formed during behind the prostomium.y of Inv metamorphosis when the imaginal disc becomes invagi- erte perisympathetic system (ARTHRO: bIrnasecta) Neurohemal or- nated beneath the larval epidermis. te Z gans connected to the transverse nerovoel s of the ventral ogy peripodial membrane (ARTHRO: Insecta) The cell layer or wall sympathetic nervous system, that release the products of surrounding the peripodal cavity and at pupation, comes to the neurosecretory cells in the ventral ganglia. form part of the epidermis of the general body wall. peritoneal membrane see peritoneum peripodial sac (ARTHRO: Insecta) In metamorphosis, the peritoneal sheath (ARTHRO: Insecta) A network of anasto- membrane enclosing the imaginal disc (bud). mosing muscle fibers that holds together the ovarioles of periproct n. [Gr. peri, around; proktos, the anus] 1. The distal the ovary. piece or segment of the body containing the anus. 2. (ANN: peritoneum n. [Gr. peri, around; tonos, strain; eous, com- Oligochaeta) The pygomere or pygidium. 3. (ARTHRO) see posed of] A thin serous membrane lining the body cavity; telson. 4. (ECHINOD) The circular membrane containing the covering and supporting the organs. peritoneal a. anus, surrounded by a varying number of embedded plates. peritreme n. [Gr. peri, around; trema, hold] 1. (ARTHRO: Che- licerata) In Acari, a concave plate surrounding a stigma perisarc n. [Gr. peri, around; sarx, flesh] (CNID: Hydrozoa) A (=spiracle). 2. (ARTHRO: Insecta) An annular sclerite sur- yellowish or brown chitinous covering of a colony that is rounding a spiracle. 3. (MOLL: Gastropoda) see peristome. secreted by the epidermis; the periderm. peritrophic membrane (ARTHRO) An extracellular sheath in perisomatic plates (ECHINOD: Crinoidea) Tegminal plates: which chitin is present, separating the apical surface of the interradials, interambulacrals, or radianal plates. mid-gut that protects the gut cells from mechanical dam- perispicular spongin (PORIF) Spongin surrounding spicules. age caused by abrasive food particles; usually loosening peristalsis n. [Gr. peri, around; stalsis, constriction] Rhythmic from the mid-gut and remaining around the food, passing movement of the wall of the enteron or other tubular or- with the feces. gans, traveling in successive contractions in one direction. perivisceral a. [Gr. peri, around; L. viscus, entrail] Surround- peristethium see mesosternum ing the viscera. peristigmatic glands (ARTHRO: Insecta) Glands that secrete a permanent haplometrosis (ARTHRO: Insecta) A colony that is hydrophobic material preventing wetting of the spiracles. founded by a single female whose initial offspring are ster- ile females, then later towards the end of the annual cycle peristome n. [Gr. peri, around; stoma, mouth] 1. The region reproductives are produced. see temporary haplometro- surrounding the mouth. 2. (ANN) Segment modified to form sis, functional haplometrosis. part of the head and surround the mouth; buccal segments. see prostomium. 3. (ARTHRO: Insecta) Membra- permanent hybrid Hybrid that maintains its heterozygosity by nous tissue around the base of the mouth. 4. (BRYO) Modi- balanced lethal factors in its genotype. fications of the area around the orifice. 5. (ECHINOD: Ophi- permanent parasite A parasite living its entire adult life uroidea) Membranous area surrounding the mouth; on the within or on a host. aboral surface of the jaw. 6. (MOLL: Gastropoda) Thickened permanent pleometrosis (ARTHRO: Insecta) In social Hymen- rim or lip around the mouth; the margin of the aperture. optera, the foundation of colonies through swarming. see peristomium n. [Gr. peri, around; stoma, mouth] (ANN: Oli- primary pleometrosis. gochaeta) The lateral and ventral margins of the mouth, permesothyridid foramen (BRACHIO) A pedicle opening found 680 681 Maggenti and Gardner On line Di ctio nar mostly within the ventral umbo. in a body, fixed or moviynogf, capable of active ingestion and Inve peronium n.; pl. -ia [Gr. perona, fibula] (CNID: Hydrozoa) digestion. see plasmatocytes.rteb rate Thick epidermal tract from the base of the tentacle on to phagocytosis n. [Gr. phagein, to eat; kZyotos, container] The log the bell. ingestion of solid particles by a cell. phagocyytic a. peroral a. [L. per, through; os, mouth] By way of, or through phagosome n. [Gr. phagein, to eat; soma, body] A mem- the mouth. brane-bound vesicle in the cytoplasm of a cell resulting perradius n.; pl. -ia [L. per, through; radius, ray] In Echino- from phagocytosis. dermata and Cnidaria, body parts and organs located along phagotroph n. [Gr. phagein, to eat; trophon, food] An organ- a limited number of radial planes; primary or 1st order ra- ism that ingests food by phagocytosis. dius. phallic gland (ARTHRO: Insecta) In some Orthoptera, a gland pervious a. [L. per, through; via, way] Perforate or open. that lies on the posterior part of the accessory gland tubule petaloid a. [Gr. petalon, leaf] Resembling petals. mass to the left of the ejaculatory duct and opens on the distal part of the left phallomere; conglobate gland. petasma n. [Gr. petasma, something spread out] (ARTHRO: Crustacea) Complex male copulatory organs with coupling phallic organ (ARTHRO: Insecta) Median intromittent appara- hooks on the first pair of pleopods. tus of males located on segment 9 and consisting of phallus or phallomeres and lobes from the phallobase; penis. petiole n. [L. petiolus, little foot] 1. A stock or stem. 2. (AR- THRO: Insecta) a. In Hymenoptera Apocrita, the narrow phallobase n. [Gr. phallos, penis; basis, bottom] (ARTHRO: In- constricted zone at the base of the gaster. b. In Formici- secta) Proximal part of the phallus of males, a large basal dae, a one or two segmented pedicel. petiolate a., petio- structure supporting the aedeagus; a thecal fold or sheath liform a. around the aedeagus; basal phallic sclerites in the wall of the genital chamber. petraliiform colony (BRYO: Gymnolaemata) In Cheilostomata, encrusting unilaminate colony loosely attached by the pro- phallocrypt n. [Gr. phallos, penis; kryptos, hidden] (ARTHRO: truding basal walls of zooids or by basally budded kenozo- Insecta) In males, a pocket of the phallobase or wall of the oids. genital chamber containing the base of the aedeagus. petricolous a. [L. petra, rock; colere, to inhabit] Dwelling phallomeres n.pl. [Gr. phallos, penis; meros, part] (ARTHRO: within stones, crevices or in hard clay. Insecta) Genital phalic lobes formed at the sides of the gonopore of males, that form an inner pair of mesomers pH A symbol of a scale measuring the acidity or alkalinity of a that unite to form the aedeagus, the intromittent organ, medium, with a value of 7.0 indicating neutral, lower val- and outer parameres that develop into claspers of variable ues indicating acidity, and higher values indicating in- form. creased values of alkalinity. phallosome n. [Gr. phallos, penis; soma, body] (ARTHRO: In- phacella n.pl.; sing. -um [Gr. phakellos, bundle] (CNID: Scy- secta) Complex structure ssurrounding the gonopore be- phozoa) Tentacle-like gastric filaments covered with gas- tween the proctiger, gonocoxite and sternum IX in male trodermis, nematocysts and gland cells. mosquitoes. phaeno- see pheno phallotheca n.; pl. -thecae [Gr. phallos, penis; theke, case] phage n. [Gr. phagein, to eat] A bacterial virus. (ARTHRO: Insecta) In males, a fold or tubular extension of phagocytes n.pl. [Gr. phagein, to eat; kytos, container] Cells the phallobase partly or completely enclosing the aedeagus. 682 683 Maggenti and Gardner On line Di ctio nar phallotreme, phallotrema n. [Gr. phallos, penis; trema, hole] jelly. b. Ventral : a tranysvoefrse row of cells opening into the Inv (ARTHRO: Insecta) In males, the opening of the duct at the floor of the pharynx between etrhte ducts of the lateral pha- bra tip of the aedeagus. ryngeal glands. 2. (NEMATA) see esotpehZageal glands. ool ogy phallus n. [Gr. phallos, penis] (ARTHRO: Insecta) The male pharyngeal skeleton see cephalopharyngeal skeleton copulatory organ; the parameres together with the pharyngeal tube (ARTHRO: Insecta) In Siphunculata, the en- aedeagus; the aedeagus; the penis. phallic a. trance to the cibarial pump. see sac tube, trophic sac. phanere n. [Gr. phaneros, visible] Any prominent tegumentary pharyngeate, nonocellate cercariae (PLATY: Trematoda) formation, i.e., setae or seta-like processes. Furcocercous cercariae that develop in sporocysts or rediae phanerocephalic pupa (ARTHRO: Insecta) In Diptera, the pu- and penetrate into a vertebrate to encyst. pal stage between the cryptocephalic pupa and the pharate pharyngo-intestinal valve see cardia adult. pharynx n.; pl. pharynges, pharynxes [Gr. pharynx, gullet] phanerocodonic a. [Gr. phaneros, visible; kodon, bell] (CNID: 1. In insects, annelids, arachnids and platyhelminths the Hydrozoa) Of or pertaining to detached and free-swimming anterior part of the foregut, between the mouth and the medusa of a hydroid colony. esophagus. 2. (NEMATA) a. The posterior portion of the phaneromphalous a. [Gr. phaneros, visible; omphalos, the stoma (esophastome); anterior stomal region of the navel] (MOLL: Gastropoda) A shell with a completely open esophagus proper. b. Sometimes used as a synonym of umbilicus; may be wide, narrow, or very minute. see esophagus. anomphalous. pharynx of Leisblein see esophageal bulb phanerotaxy n. [Gr. phaneros, visible; taxis, arrangement] phasic castration Pertaining to individuals in which the go- (ARTHRO: Chelicerata) The number and arrangements of nads are inhibited in development due to seasonal or onto- phaneres. phanerotactic a. genetic conditions. see alimentary castration, nutricial phanerotoxic a. [Gr. phaneros, visible; toxikos, poison] (AR- castration. THRO: Insecta) Erucism caused by toxic setae of lepidop- phasic muscle (MOLL: Bivalvia) In oysters, the fast muscle; terous caterpillars. see lepidopterism. adductor muscle that reacts quickly but does not endure. phaosome n. [Gr. phaos, light; soma, body] A light-sensitive phasma n.; pl. -ata [Gr. phasma, apparition] (NEMATA: Adeno- epidermal organelle; eyespot. phorea) Phasmid-like areas on the tails of some Desmo- pharate a. [Gr. pharos, garment] (ARTHRO: Insecta) 1. A stage scolecida; tiny canals lead away from these structures, but in metamorphosis that does not usually represent a distinct no phasmidial gland has been found. morphological stage. 2. Any stage of development that re- phasmid n. [Gr. phasma, apparition; edios, like] (NEMATA) One mains within the cuticle of the preceding stage. 3. Pertain- of a pair of lateral caudal pores (sensilla) connecting with a ing to the last larval instar forming the puparium and from glandular pouch that alledgedly functions as a chemore- which an adult emerges. ceptor. see scutellum. pharyngeal canal (CTENO) The stomodeal canal. Phasmidia see Secernentea pharyngeal ganglion see corpora cardiaca phena pl. of phenon pharyngeal glands 1. (ARTHRO: Insecta) In Hymenoptera: a. phene n. [Gr. phainein, to appear] A genetically controlled Lateral : a long coiled chain of follicles in the antero-dorsal phenotypic character. region of the head of worker Apoidea; the source of royal 684 685 Maggenti and Gardner On line Di ctio nar phenetic classification A classification based on phenotypes hemocoel. y of Inv rather than evolution from a common ancestor. erte phoba n.; pl. -ae [Gr. phobe, tuft] (AbRraTHRO: Insecta) In many te Z pheneticist see numerical phenetics scarabaeoid larvae, a dense hair-like osoel t of projections, ogy phenetic ranking Ranking into categories according to degree often forked, at the posterior inner edge of the paria. of overall similarity. phobotaxis see klinokinesis phengophil a. [Gr. phengos, light; philos, loving] Preferring phonation n. [Gr. phone, sound] The production of sounds. light. phonoreceptor n. [Gr. phone, sound; L. receptor, receiver] A phengophobe a. [Gr. phengos, light; phobos, fear] Shunning sense organ responsive to sound. light. phoresis n. [Gr. phoreus, carrier] A form of symbiotic relation- phenogram n. [Gr. phainein, to appear; gramme, mark] A ship when the symbiont, the phoront, is mechanically car- diagram showing degree of similarity among taxa. ried about by its host; neither being physiologically de- phenology n. [Gr. phainein, to appear; logos, discourse] A pendent on the other. see phoretic host, transport host. branch of science concerned with periodic biotic events phoresy see phoresis such as flowering, breeding and migration. phoretic host One partner in a phoretic relationship; an or- phenome n. [Gr. phainein, to appear] The phenotypic charac- ganism that transports another microorganism to which it ters of an organism. is nonsusceptible; a transport host; a mechanical vector. phenomenology see phenology phoretomorph n. [Gr. phoretos, carried; morphe, form] (AR- phenon n. [Gr. phainein, to appear] A group of phenotypically THRO: Chelicerata) In mites, forms adapted especially for similar organisms. phoretic transport. phenotype n. [Gr. phainein, to appear; typos, type] The Phoronida, phoronids n.; n.pl. [L. Phoronis, surname of Io] physical appearance of an individual as a result of interac- Phylum or class of the phylum Lophophorata; marine, en- tion between genotype and environment. terocoelic coelomates, free-living in secreted chitinous, cylindrical tubes. pheromone n. [Gr. phero, bear; hormao, to instigate] A chemical substance secreted by an animal on the substra- phoront n. [Gr. phoretos, carry] Any organism mechanically tum, on the bodies or possibly in the air, that influences conveyed by another organism. see phoresis. the behavior of other individuals of the same or different phospholipids n.pl. [Gr. phosphoros, light bringer; lipos, fat] species, such as trail-marking or following, alarm, dispers- Lipids containing phosphorus and nitrogen, found in all ants, territorality, synchronization, aggregation and sex cells. attractants. phosphorescent see bioluminescence phialiform, phialaeform a. [L. phiala, shallow cup; forma, photic zone Surface waters penetrated by light. see aphotic shape] Cup-shaped; saucer-shaped. zone. philopatry n. [Gr. philos, loving; patrios, fatherland] The ten- photochemical a. [Gr. phos, light; chemeia, infusion] Per- dency of an individual to either stay in or return to its taining to any chemical reaction produced by exposure to home or adopted locality. light. phlebedesis, phleboedesis n. [Gr. phleps, vein; desis, a photogenic a. [Gr. phos, light; genes, born] Light producing; binding together] Suppression of the true coelom by a luminescent. 686 687 Maggenti and Gardner On line Di ctio nar photokinesis n. [Gr. phos, light; kinesis, movement] A kinesis phragmocone n. [Gr. phraygomf os, fence; konos, cone] (MOLL: Inv in response to stimulation by visual cognizance. Cephalopoda) A thin, conical inetreternally chambered shell. bra te Z photophil n. [Gr. phos, light; philos, loving] Light-loving. see phragmocyttarous a. [Gr. phragmos, fenocoel; kyttaros, parti- ogy phengophil. tion] (ARTHRO: Insecta) Pertaining to nests, especially of photophobic, photophobe a. [Gr. phos, light; phobos, fear] social wasps, in which brood combs are attached laterally Shunning or avoiding light. see lucifugous, lucipetal, to the inner surface of the sack-like envelope. phengophobe. phragmosis n. [Gr. phragmos, fence] (ARTHRO: Insecta) A photophobotaxis n. [Gr. phos, light; phobos, fear; taxis, ar- method used by Formicidae and Termitidae in which the rangement] Movement involved in the avoidance of light; head or tip of the abdomen is used as a plug for the nest negative tropism. entrance. photophore n. [Gr. phos, light; pherein, to bear] A light pro- phthiriasis n. [Gr. phtheir, louse; -iasis, disease] A skin condi- ducing organ of certain marine Hydrozoa, Crustacea and tion caused by an infestation of certain Siphunculata. Cephalopoda. phthisaner n. [Gr. phthisis, decline; aner, male] (ARTHRO: In- photopic see apposition eye secta) A pupal male Formicidae in which the wings are suppressed and the legs, head, thorax and antennae re- photoreactivation reaction Partial reversal of damage to main abortive due to the extraction of the juices of the late biological systems by ultraviolet light by longer wave length larval or semi-pupal stage by the larval ant chalcid wasp of light. the family Eucharitidae. see phthisogyne. photoreceptor n. [Gr. phos, light; L. receptor, receiver] A phthisergate n. [Gr. phthisis, decline; ergates, worker] (AR- sense organ responsive to light. THRO: Insecta) In Formicidae, an emaciated pharate adult photosynthesis n. [Gr. phos, light; synthesis, place together] worker due to parasitic feeding in the larval, prepupal or The formation of carbohydrates from carbon dioxide and pharate adult stage by the larval ant chalcid wasp of the water by the absorption of light by chlorophyll. family Eucharitidae; an infra-ergatoid form. phototaxis n. [Gr. phos, light; taxis, arrangement] The phthisodinergate n. [Gr. phthisis, decline; deinos, terrible; movement in response to the stimulus of light. see helio- ergate, worker] (ARTHRO: Insecta) In Formicidae, pupated taxis. soldier denied adulthood due to parasitism. phototelotaxis n. [Gr. phos, light; telos, end; taxis, arrange- phthisogyne n. [Gr. phthisis, decline; gyne, woman] (ARTHRO: ment] The direct movement of an animal toward shade. Insecta) In Formicidae, a form resulting from a female phototonus n. [Gr. phos, light; tonos, tension] 1. Sensitive- larva under the same parasitism as a phthisaner. ness to light. 2. Muscle tonus stimulated by light. phylacobiosis n. [Gr. phylax, guard; biosis, manner of life] phototropism n. [Gr. phos, light; tropos, turn] Movement de- (ARTHRO: Insecta) A form of symbiosis in which a species of termined by the direction of incident light. photropic a. Formicidae lives in the hills of Termitidae supposedly acting as a guard or protector. phragma n.; pl. -mata [Gr. phragmos, fence] 1. An inwardly extending process. 2. (ARTHRO: Insecta) In winged forms, phylactocarps n.pl. [Gr. phylax, guard; karpos, fruit] (CNID: an internal plate or invagination of the dorsal wall for the Hydrozoa) Protective modifications for the gonangia of Hy- attachment of muscles. phragmatal a. see prephragma, droida. see corbula. postphragma. Phylactolaemata, phylactolaemates n.; n.pl. [Gr. phylax, guard; laimos, throat] A small, basically cylindrical, mono- 688 689 Maggenti and Gardner On line Di ctio nar morphis, freshwater class of Bryozoa, with a crescentic lo- zoa) In Siphonophora, ya otfhick, gelatinous leaf-like or hel- Inve phophore and an epistome. met-shaped medusoid containritnegb a simple or branched rate phylacum n. [Gr. phylax, guard] (ARTHRO: Diplopoda) In gastrovascular canal, protective in funZocotion; a hydrophyl- log Julida, the outer leaf-like flange of the solenomerite. lium; a bract. y phyletic a. [Gr. phyle, tribe] Pertaining to a line of descent. phylogeny n. [Gr. phyle, tribe; genesis, beginning] The study see phylogeny. of the history of the lines of evolution of a species or higher group of organisms; distinguished from ontogeny. see phyletic correlation The occurrence of characters that are classification. phylogenetic a. phenotypic manifestations of a well-integrated ancestral gene complex. phylogerontic a. [Gr. phyle, tribe; gerontos, old man] In phylogeny, referring to the decadence of the old age stage. phyletic evolution Genetic changes that occur within an evo- see paracme, typolysis. lutionary line. phylogram n. [Gr. phyle, tribe; gramme, mark] A tree-like phyllidium n. [Gr. phyllon, leaf] (PLATY: Cestoda) Leaf-shaped diagram indicating degree of relationship among taxa. outgrowth on the side of the scolex; bothridium. phyloneanic a. [Gr. phyle, tribe; neanikos, youthful] Adoles- phylliform a. [Gr. phyllon, leaf; L. forma, shape] Leaf-shaped. cent stage in phylogeny. see neanic. phyllobombycin n. [Gr. phyllon, leaf; L. bombyx, silkworm] phylum n.; pl. phyla [Gr. phyle, tribe] One of the higher taxo- (ARTHRO: Insecta) In Lepidoptera, a crystalline derivative of nomic categories of the animal kingdom. chlorophyll found in the feces of silkworms. physa n. [Gr. physa, bladder] (CNID: Anthozoa) The bulbous phyllobranch, phyllobranchia a. [Gr. phyllon, leaf; branchia, base of burrowing Actinaria. gills] (ARTHRO: Crustacea) A gill with paired lamellar branches (leaflike filaments) arising from the branchial physergate n. [Gr. physa, bladder; ergate, worker] (ARTHRO: axis. phyllobranchiate a. Insecta) In Hymenoptera Formicidae, large workers capable of egg production, but mainly utilized for honey stor- phyllode n. [Gr. phyllon, leaf] (ECHINOD: Echinoidea) Petal-like age. arrangement of ambulacra around the peristome. physiogenesis n. [Gr. physis, nature; genesis, beginning] phyllophagous a. [Gr. phyllon, leaf; phagein, to eat] Feeding Differentiation of the embryo leading to distinctive differ- upon leaf tissue. ences between and within regions. see histogenesis. phyllopod(ium) n.; pl. -dia [Gr. phyllon, leaf; pous, foot] physiology n. [Gr. physis, nature; logos, discourse] The study (ARTHRO: Crustacea) Leaflike thoracic appendages. of cell and tissue function and activities of living organisms. phyllosoma n. [Gr. phyllon, leaf; soma, body] (ARTHRO: physogastry n. [Gr. physa, bladder; gaster, belly] (ARTHRO: Crustacea) In Decapoda, a larval stage in the development Insecta) Swelling of the abdomen due to hypertrophy of fat of Palinuridae, characterized by a flattened leaf-shaped bodies, ovaries, or both. planktonic form; equivalent to zoea stage of other crusta- cean larvae. phytoalexins n. [Gr. phyton, plant; alexein, to protect] A group of protective substances synthesized by plants as a phyllotriaene n. [Gr. phyllon, leaf; triaina, trident] (PORIF) result of infection, thought to aid in resistance to nema- Tetractinal spicule with three rays of flattened discs and the todes, bacteria and environmental accidents. fourth ray short and pointed. phytobiotic a. [Gr. phyton, plant; bios, life] Living within phyllozooid n. [Gr. phyllon, leaf; zoon, animal] (CNID: Hydro- plants. 690 691 Maggenti and Gardner On line Di ctio nar phytoparasite n. [Gr. phyton, plant; para, beside; sitos, food] of the choanocyte ychoaf mbers. see exopinacocyte, Inv A plant parasite. phytoparasitic a. endopinacocyte, basopinacoerctyete. bra te Z phytophaga n.pl. [Gr. phyton, plant; phagein, to eat] A mem- pinacoderm, pinnacoderm n. [Gr. pinax, toaobl let; derma, skin] ogy ber of a vegetable-eating group of animals. (PORIF) The outer delimiting membrane layers of pinaco- phytophagous a. [Gr. phyton, plant; phagein, to eat] Feeding cytes; ectosome. on plants; herbivorous. pinaculum n. [Gr. pinax, tablet] (ARTHRO: Insecta) Small, flat phytophilous a. [Gr. phyton, plant; philos, loving] Pertaining or slightly raised chitinized area with one to four setae. to species that live or feed on plants. pincers n.pl. [OF. pincier, to pinch] Any structure that resem- piceous a. [L. piceus, pitchy] Pitch-black, brownish or reddish bles the grasping end of pincers. black. pinna n.; pl. pinnae [L. feather] 1. A wing or fin. 2. (ARTHRO: pick n. [A.S. pic, pike] (ARTHRO: Insecta) In Psocoptera, a de- Insecta) The part of the trumpet of Culicidae pupae from tached styliform process of the lacinia. the apex to an imaginary line drawn approximately perpendicular to the longitudinal axis at the proximal margin pictured a. [L. pictura, picture] (ARTHRO: Insecta) Pertaining to of the spiracular opening. spots or bands on wings. pinnafid n. [L. pinna, feather; findare, to split] (ARTHRO: In- pigment n. [L. pignere, to paint] Coloring matter of plants and secta) Wings that are deeply divided, as in Thysanoptera. animals. pinnate a. [L. pinnatus, feathered] 1. Feather or fern-like in pigmenta cercaria (PLATY: Trematoda) Amphistome cercaria appearance. 2. Having hairs, thorny or lateral processes on with stellate melanophores. see diplocotylea cercaria. opposite sides. pigment cell A chromatophore; a chromocyte. pinnules n.pl. [L. dim. pinna, feather] 1. (ANN: Polychaeta) pileus n.; pl. pilei [L. pileus, cap] (CNID: Scyphozoa) The um- The lessened lateral paddle-like parapodia. 2. (ECHINOD: brella-shaped structure of a jellyfish. Crinoidea) Short tapering, flexible lateral projections or pilidium n. [L. dim. pileus, cap] (NEMER) A helmet-shaped branches on either side of the arms. free-swimming larva. pinocytosis n. [Gr. pino, drink; kytos, container] Ingestion or pilifer n. [L. pilus, hair; ferre, to carry] (ARTHRO: Insecta) In absorption of surrounding fluids by a cell, that forms a Lepidoptera, one of a pair of lateral projections on the la- vesicle by incupping of the surface membrane. brum. pinosome n. [Gr. pino, drink; soma, body] Intracellular vesicle piliferous a. [L. pilus, hair, ferre, to carry] Bearing hair. containing material taken up by pinocytosis. pillar n. [L. pila, pillar] 1. (MOLL: Bivalvia) An inwardly pro- pinule, pinulus n. [L. dim. pinna, feather] (PORIF) A spicule jecting outer shell layer along the length of the lower valve. resembling a fir tree because of small spines developing on 2. See columella one ray, usually 5 rayed spicules. pillared eye see turbinate eye pioneer community Organisms that establish a new community on bare ground. pilose a. [L. pilus, hair] Hairy; with fine, soft hair. piping n. [L. pipare, to chirp] (ARTHRO: Insecta) In Apis, sound pilus n.; pl. pili [L. pilus, hair] A hair or hair-like structure. made by young queens after their emergence. pinacocyte n. [Gr. pinax, tablet; kytos, container] (PORIF) The piptoblast n. [Gr. piptein, to fall; blastos, bud] (BRYO) An en- large flat polygonal cells that line all surfaces, except those capsulated bud not released from parent colony. 692 693 Maggenti and Gardner On line Di ctio nar piriform a. [L. pirum, pear; forma, shape] Pear-shaped; pyri- of a ciliated planula, puyrpoofrted to be a stage in the evolu- Inv form. tion of higher animals. erte bra te Z piscicolous a. [L. piscis, fish; colere, to inhabit] Living in fish. plane a. [L. planus, flat] 1. A smooth flatooslurface, devoid of ogy pisciform n. [L. piscis, fish; forma, shape] Fish-shaped. markings or configurations. 2. A plasmagene or plasmid. pisiform a. [L. pisum, a pea; forma, shape] Pertaining to pea- plane of symmetry The median plane dividing a bilaterally shaped; a small globular body. symmetrical animal into two halves that are mirror images of each other. pit gland (ROTIF: Monogononta) A secretion gland in the form of a cuplike pit on the corona. planidium n.; pl. -idia [Gr. dim. plane, wanderer] (ARTHRO: Insecta) The free-living, active, first-instar larva of some pith n. [A.S. pitha, marrow, pith] (PORIF) A central region of parasitic hypermetamorphic Neuroptera, Coleoptera (triun- more diffuse collagen found within a spongin fiber. gulin), all Strepsiptera (triungulinid), Diptera, Lepidoptera pivotal axis (MOLL: Bivalvia) An axis at the ligament about and Hymenoptera. which the valves rotate. planipennate a. [L. planus, flat; penna, wing] Flat-winged. pivotal bar (BRYO) In Cheilostomata avicularia, a complete planispiral a. [L. planus, flat; spira, coil] (MOLL: Gastropoda) skeletal rim on which the fixed end of the mandible is Shells coiled in a single plane like a flat spiral with sym- hinged. metrical sides; loosely used for shells whorled in a discoid placids n.pl. [Gr. plax, plate] (KINOR) Large plates located on form with asymmetrical sides. see isostrophic. the 3rd zonite (neck) with retractable necks; nonre- plankton n. [Gr. plankton, wandering] 1. Pelagic animals col- tractable are located on the 2nd zonite and sometimes re- lectively, distinguished from coast or bottom forms. 2. A ferred to as a closing apparatus. general name for animals (zooplankton) or plants (phyto- placoid a. [Gr. plax, plate] Plate-like. plankton) living at or near the surface of the water. see placoid sensilla see sensillum placodeum seston. plaga a.; pl. plagae [L. plaga, stripe] A stripe or streak of planktotrophic larva (BRYO: Gymnolaemata) Free-living, cili- color. plagate a. ated larvae with a long motile life before metamorphosis. plagiosere n. [Gr. plagios, oblique; serere, to join] The suc- planoblast (CNID: Hydrozoa) The free-swimming medusa form. cession of plant diversion into a new course by biotic factor planorboid a. [L. planus, flat; orbis, a circle] Flat and orb-like. or factors. see prisere. planta n.; pl. plantae [L. planta, sole of foot] (ARTHRO: In- plagiotriaene a. [Gr. plagios, oblique; triaina, trident] (PORIF) secta) In some larval forms, an apical area of the leg In tetraxons, having clads directed forward and making an bearing a row or circle of outwardly curved hooks or cro- angle of about 45° with the produced axis of the rhab- chets that aid in gripping. dome. plantar a. [L. planta, sole of foot] (ARTHRO: Insecta) Of or plagula n. [L. plagula, veil] (ARTHRO: Chelicerata) In Arach- pertaining to the planta or sole of the foot. nida, a ventral plate protecting the pedicle. plantella see empodium plait n. [L. plicare, to fold] 1. Longitudinally folded or laid in plantula n.; pl. -lae [L. plantula, small sole] (ARTHRO: Insecta) pleats. 2. (MOLL: Gastropoda) Applied to folds on the colu- A pad-like sole on the underside of the tarsal segment. see mella or pillar. pulvillus. planaea n. [L. planus, flat] A conjectured organism in the form 694 695 Maggenti and Gardner On line Di ctio nar planula n.; pl. -lae [L. planus, flat] (CNID) A free-swimming plates n.pl. [L. plattus, flat]y o(fARTHRO: Insecta) In Diaspidinae, Inv ciliated larva, cylindrical to ovoid with two cell layers (ecto- gland spines of the pygidiumerttheat are multiple branched, bra derm and endoderm). with or without a duct. te Z ool ogy plaques n. [F. plaque, plate] 1. (NEMATA) Cuticular "warts". 2. platyform larva (ARTHRO: Insecta) An extremely flattened (POGON) Small scales of cuticle on the trunk papillae. larva; an onisciform larva. plasma n. [Gr. plasma, formed or molded] The fluid portion of Platyhelminthes n.pl. [Gr. platys, flat; helminthos, of worms] blood or lymph. A phylum of acoelomate animals commonly called flat- plasmagene n. [Gr. plasma, formed or molded; gennaein, to worms, including the flukes, tapeworms and turbellarians. produce] A genetic factor located in the cytoplasm, rather platymyarian a. [Gr. platys, flat; mys, muscle] (NEMATA) than in the nucleus; a plasmid; a plane. Having fibers of the muscle cells adjacent and perpendicu- plasmalemma see plasma membrane lar to the hypodermis. see coelomyarian. plasma membrane A unit membrane surrounding the cell's plectanes n. [Gr. plektos, twisted] (NEMATA) Cuticular plates protoplasm; cell membrane; plasmalemma. that function as supports for the male genital papillae. plasmatocytes n.pl. [Gr. plasma, formed or molded; kytos, plectolophe n. [Gr. plektos, twisted; lophos, crest] (BRACHIO) container] Small to large polymorphic hemocytes with a A lophophore where each branchium has a U-shaped side round to elongate nucleus and with either homogeneous or arm with a double row of paired filamental appendages, finely granular or finely vacuolated cytoplasm. terminating distally in a medial plano-spire normal to commissural plane with a single row of paired appendages. plasmid n. [Gr. plasma, formed or molded; eidos, like] DNA plectolophous a. molecules that are not attached to a chromosome but are inherited regularly. plectrum n. [L. plectrum, a tool for plucking a stringed instrument] (ARTHRO: Insecta) In Coleoptera, a single scraper plasmon n. [Gr. plasma, formed or molded] All extrachromo- used against a roughened file (strigil) that causes a mem- somal hereditary determinents; plasmotype. brane to vibrate and therefore produce sound. plasmosome see nucleolus plegma n.; pl. plegmata [Gr. plegma, plaited] (ARTHRO: In- plasmotype see plasmon secta) In scarabaeoid larvae, a single fold. see plegma- plastic a. [Gr. plasma, a thing molded] Formative. tium, proplegmatium. plastids n.pl. [Gr. plastos, formed; dim. -idion] A generalized plegmatium n.; pl. -tia [Gr. plegma, plaited] (ARTHRO: In- term for cell organelles. secta) In scarabaeoid larvae, a lateral paired area with a plicate, sclerotized surface, bordered by marginal pleg- plastosomes see mitochondria mated spines with acanthoparia. plastron n. [F. plastron, breast plate] 1. The chorion of some pleiomorphic, pleomorphic a. [Gr. pleion, more; morphe, eggs. 2. (ARTHRO: Insecta) A permanent film of air retained form] Having the ability to change shape; polymorphic, or by hairs on the outside of an aquatic insect body allowing a type of polymorphism. an air water interface for gaseous exchange. 3. ECHINOD: Echinoidea) In Spatangoida, a ventral interambulacral area pleiomorphism, pleomorphism n. [Gr. pleion, more; mor- between the labrum and periproct, sometimes with special phe, form] 1. Polymorphism. 2. A type of polymorphism spination. exhibited as several different stages in a life cycle. plate organ see sensillum placodeum pleiotrophy, pleiotropism n. [Gr. pleion, more; tropein, to 696 697 Maggenti and Gardner On line Di ctio nar turn] Multiple phenotypic effects of a single gene. primitive form of assoycioaftion approaching symbiosis. 2. Inv (ARTHRO: Insecta) Living in cloesreteproximity, i.e., compound pleomere see abdominal somite bra nests of different species of FormicidteaeZ and Isoptera; rudi- ool pleometrosis n. [Gr. pleion, more; metros, mother] (ARTHRO: mentary form of social symbiosis. ogy Insecta) A colony containing two or more fertilized egg- laying females (queens); social colony foundation; mono- plesiomorphy n. [Gr. plesios, near; morphos, form] A term metrosis; polygyny. pleometrotic a. see pri- referring to original or primitive characters being retained; mary/periodical pleometrosis, permanent pleometro- normally used in cladistic taxonomy. see apomorphy, sis, temporary pleometrosis, secondary pleometrosis, symplesiomorph. haplometrosis. plesiotype n. [Gr. plesios, near; typos, type] A specimen upon pleomorphic see pleiomorphic which a subsequent or additional description or illustration of a previously named species is based. pleomorphism see pleiomorphism pleura n.pl; sing. pleuron [Gr. pleura, side] (ARTHRO) A lateral pleon, pleonites see abdomen region on the sides of the body of certain arthropods; for pleonic hinges (ARTHRO: Crustacea) In Decapoda, mid-lateral crustaceans see epimere. pleural a. hinges that lock together the pleural somites. pleural angle (MOLL: Gastropoda) In the plane through entire pleophyletic see polyphyletic shell axis, angle between two straight lines lying tangential pleopod n. [Gr. plein, to swim; pous, foot] (ARTHRO: Crusta- to the last two whorls on opposite sides. cea) In Malacostraca, paired appendages of any of the first pleural apophyseal pit (ARTHRO: Insecta) In Diptera, an ex- 5-6 somites, adapted for swimming; swimmeret. ternal depression at the point of origin of the pleural pleotelson n. [Gr. plein, to swim; telson, limit] (ARTHRO: apophysis, usually situated at the lower end of the pleural Crustacea) The telson and one or more abdominal somites suture. combined by fusion. pleural apophysis (ARTHRO: Insecta) The internal arm of the plerergate see replete pleural ridge that aids in resistance to the lateral elasticity of the thorax when in flight. see sternal apophyses. plerocercoid n. [Gr. pleres, full; kerkos, tail; eidos, like] (PLATY: Cestoda) An elongate metacestode developed from pleural area 1. (ARTHRO: Insecta) In Hymenoptera, the lateral a procercoid. area of the propodeum, next to the metapleurum; divided into three parts, the first (front), second (middle), with the plerocercoid stage (PLATY: Cestoda) A third-stage larva of first and second usually united, and third (hind). 2. (MOLL: Pseudophyllidea and Proteocephalidea with a solid body. Polyplacophora) Side slopes, not including the jugal area or plerocercus stage (PLATY: Cestoda) In Trypanorhyncha, a lateral areas where the latter are well defined. metacestode in which the posterior forms a bladder (blas- pleural arm see pleural apophysis tocyst) into which the rest of the body withdraws. pleural coxal process (ARTHRO: Insecta) The process of the plerocestoid n. [Gr. pleres, full; kestos, girdle; eidos, like] pleuron at the base of the pleural ridge with which the coxa (PLATY: Cestoda) The stage emerging from an oncosphere articulates. that upon development is known as a metacestode. pleuralia n.pl. [Gr. pleura, side] (PORIF) Spicules protruding plesioasters n.pl. [Gr. plesios, near; aster, star] (PORIF) from lateral surface. Streptasters with few spines from a very short axis. pleural lobe see epimere plesiobiosis n. [Gr. plesios, near; biosis, manner of life] 1. A 698 699 Maggenti and Gardner On line Di ctio nar pleural membrane (ARTHRO: Insecta) The membrane occur- pleuron see pleura y of Inv ring between the tergum and sternum of a body segment. erte pleuropod see precoxa bra te Z pleural ridge (ARTHRO: Insecta) A vertical strengthening ridge ool pleuropodium n.; pl. -dia [Gr. pleuron, sideo;gypous, foot] 1. above the coxa that divides the pleuron into an anterior (ARTHRO: Insecta) Lateral embryonic band formed by a episternum and a posterior epimeron, well developed in modified abdominal leg. 2. (MOLL: Gastropoda) One of a wing bearing segments and continuing dorsally into the pair of mantle lobes. pleural wing process; the entopleuron. see pleural apophysis. pleurosternal suture see mesopleurosternal suture pleural sclerites see pleura pleurosternite see laterosternite pleural sulcus see mesopleural suture pleurosternum n. [Gr. pleuron, side; sternon, chest] (ARTHRO: Insecta) A thoraxic sternal plate that facilitates the limb pleural suture 1. (ARTHRO: Crustacea) The line of separation bases; the coxosternum. pleurosternal a. of carapace in molting. 2. (ARTHRO: Insecta) A suture on a thoracic pleuron extending from the base of the wing to the pleurostoma n. [Gr. pleuron, side; stoma, mouth] (ARTHRO: base of the coxa, separating the episternum and epimeron; Insecta) The region of the subgena above the mandible. referred to as pro-, meso-, or metapleural ridge. pleurostomal a. pleural wing process (ARTHRO: Insecta) 1. The dorsal margin pleurostomal suture (ARTHRO: Insecta) The part of the sub- of the pleural ridge that articulates with the second axillary genal sulcus above the mandible. sclerite in the wing base. 2. In Culicidae mesothorax, lo- pleurotergite n. [Gr. pleuron, side; L. tergum, back; Gr. -ites, cated posterior to the basalare at the apex of the posterior nature of] (ARTHRO: Insecta) 1. A sclerite containing both mesanepisterum; in the metathorax, behind the basalare at pleural and tergal elements. 2. In Diptera, the lateral area the apex of the metepisternum. of the mesopostnotum, above the metathoracic spiracle; in pleurella see sternopleurite mosquitoes, divisible into lower and upper pleuotergites, represented by apodemes internally. pleurembolic proboscis (MOLL) A partially invaginable proboscis with the distal part enclosed in a proboscis sheath. pleurothetic a. [Gr. pleuron, side; thatos, placed] (MOLL: Bi- see acrembolic proboscis. valvia) Resting on its side, especially in regard to oysters. pleurepimere see epimere pleuston n. [Gr. pleustes, sailor] Free-floating macroorgan- isms. pleurergate n. [Gr. pleuron, side; ergate, worker] (ARTHRO: Insecta) In Formicidae, a worker capable of ingesting liquid plexus n.; pl. plexuses [L. plexus, a twining] A network of food into its gaster until it becomes a spherical sac. interlaced nerves or blood vessels. pleurite n. [Gr. pleuron, side; -ites, nature of] (ARTHRO) A lat- plica n.; pl. -cae [L. plicare, to fold] 1. A bend, fold, wrinkles, eral sclerite of a somite; for crustaceans see epimere. crenulations or scallops; annulets. 2. (MOLL: Bivalvia) a. A lamellibranch gill in which the lamella are thrown into verti- pleurobranch n. [Gr. pleuron, side; branchia, gills] (ARTHRO: cal folds; the apex is farthest from the interlamellar cavity. Crustacea) In Decapoda, a gill attached directly to the body b. Fold or costa involving the entire thickness of the shell wall; pleurobranchia. wall; plication. pleurolophocercous cercaria (PLATY: Trematoda) A gymno- plica analis see vannal fold cephalous type cercaria with a pair of fin folds; parapleurolophocercous cercaria. plica jugalis (ARTHRO: Insecta) The jugal fold or radial line of 700 701 Maggenti and Gardner On line Di ctio nar folding of wings, setting off the jugal region from the van- In Gnathiidea Isopoda, ythoef first thoracopod of the male; it Inv nal region; axillary furrow, plica anojugalis. may be flattened and cover thertbeuccal cavity or in juveniles bra be shaped as a hook. te Z plicate a. [L. plicare, to fold] Folded; parallel ridges or striae ool ogy appearing as folds or pleats. pneumatization n. [Gr. pneuma, air] (ARTHRO: Insecta) A plication n. [L. plicare, to fold] A minute fold or ridge. plica- process completed in an embryonic tracheal system when tulate a. liquid is replaced by gas. pneumatized a. plica vannalis see vannal fold pneumatized a. [Gr. pneuma, air] Having air cavities. pliciform a. [L. plicare, to fold; forma, shape] Having a plait- pneumatocodon n. [Gr. pneuma, air; kodon, bell] (CNID: Hy- like form. drozoa) In Siphonophora, the external wall of a float. ploidy n. [Gr. aploos, onefold; edios, like] A term referring to pneumatophore n. [Gr. pneuma, air; phoreus, bearer] (CNID: the number of chromosome sets. Hydrozoa) In Siphonophora, a muscular organ that pos- sesses a gas secreting gland and functions as an air sac plumbeous a. [L. plumbum, lead] Lead-colored. float of a colony. plume n. [L. pluma, feather] Feather-like structures. plumate pneumatosaccus n. [Gr. pneuma, air; sakkos, sac] (CNID: a. Hydrozoa) In Siphonophora, an air sac; an internal subum- plumicome n. [L. pluma, feather; coma, hair] (PORIF) A spi- brellan wall. cule with plume-like tufts. pneumostome n. [Gr. pneuma, air; stoma, mouth] (MOLL: plumoreticulate skeleton (PORIF) A type of skeletal con- Gastropoda) A pore connecting the pulmonate lungs with struction having fibers or spicule tracts diverge in plumose the exterior. fashion, still retaining cross-connections. see plumose pneumotaxis n. [Gr. pneuma, air; taxis, arrangement] A re- skeleton. action to gases, particularly carbon dioxide. plumose a. [L. pluma, feather] Having fine processes on oppo- poculiform a. [L. poculum, cup; forma, shape] Cup-shaped; site sides; feather-like. goblet-shaped. plumose skeleton (PORIF) A type of skeletal construction pod n. [ME. pod, bag] (ARTHRO: Insecta) Eggs cemented to- having diverging fibers or spicule tracts showing few if any gether in a mass, particularly in Orthoptera. cross-connections. see plumoreticulate skeleton. podeon see propodeum, metapodeon plurilocular a. [L. plus, more; loculus, little place] With 2 or more loculi or compartments; multilocular. podial opening/pore (ECHINOD: Asteroidea) The passage between ambulacrals for passage of the tube foot. plurinuclear a. [L. plus, more; nuclear, kernal] Having many nuclei present, as in syncytium. podilegous a. [Gr. pous, foot; legere, to collect] (ARTHRO: In- secta) Having pollen baskets on the legs. pluriseptate n. [L. plus, more; septum, partition] With multiple septa. podite n. [Gr. pous, foot] (ARTHRO) A limb segment; podomere. pluteus larva, dipluerula (ECHINOD) A free-swimming, bilaterally symmetrical larva of the echinoderm classes Ophiur- podium n.; pl. podia [Gr. pous, foot] (ECHINOD: Asteroidea) oidea and Echinoidea, characterized by the cilia extending The cyclindrical outer part of the tube foot. onto arms projecting from body. podobranch n. [Gr. pous, foot; branchia, gills] (ARTHRO: plyopod n. [Gr. plynos, basin; pous, foot] (ARTHRO: Crustacea) Crustacea) Gills borne on the coxa of the thoracopod; po- 702 703 Maggenti and Gardner On line Di ctio nar dobranchia. exactly alike. 2. The dyevoef lopment of two or more larval Inv forms of the same sex. poeceilrotegonous a. see poecilog- podocephalic glands (ARTHRO: Chelicerata) In actinotroch bra eny. te Z Acari, ancestrally four glands near the base of leg I; ante- ool ogy rior, median, coxal, and lateral glands. poecilogyny n. [Gr. poikilos, various; gyne, wife] (ARTHRO: podocyst n. [Gr. pous, foot; kystis, bladder] (MOLL: Gastro- Insecta) More than one form of female. poda) A sinus in the foot. poecilonymy, pecilonymy n. [Gr. poikilo, varied; onyma, podocyte see plasmatocyte name] 1. The use of two or more terms to indicate the same thing. 2. A synonym, i.e., a systematic name, as of a podomere n. [Gr. pous, foot; meros, part] (ARTHRO) An indi- species or genus, being designated and later regarded as vidual segment of a limb; a podite. an incorrect form, rejected and replaced with another more podophthalmite n. [Gr. pous, foot; ophthalmos, eye] (AR- correctly applied. THRO: Crustacea) In segmented eyestalks, one of 2 seg- Pogonophora, pogonophorans n.; n.pl. [Gr. pogonophoros, ments bearing the cornea. wearing a beard] A phylum of sedentary marine worms podosoma n. [Gr. pous, foot; soma, body] (ARTHRO: Chelicer- that are the only nonparasitic metazoans that lack a ata) In Acari, the region of the body that bears the legs. mouth, gut or anus, and are commonly called beard podospermia n. [Gr. pous, foot; sperma, seed] (ARTHRO: Che- worms. licerata) A type of sperm transfer by the male chelicera poikilonymy n. [Gr. poikilo, varied; onyma, name] The com- (gonopod) of certain Acari, to the paired orifices of the fe- bining of names or terms from different systems of nomen- male receptaculum seminis. see tocospermia. clature. podous n. [Gr. pous, foot] A walking leg. poikilosmotic a. [Gr. poikilos, various; osmos, impulse] Hav- poecilacanthous armature (PLATY: Cestoda) Armature with ing an internal osmotic pressure varying with the environ- hooks on tentacles of differing sizes, shapes and arrange- mental medium. ments with chainettes present. poikilothermal a. [Gr. poikilos, various; thermos, warm] Cold- poecilandry n. [Gr. poikilos, various; aner, man] More than blooded; having a body temperature that rises or falls with one form of male. see poecilogyny. the environmental temperature; ectothermal. poikilotherm n. see homoiothermal. poecilocyttares n.pl. [Gr. poikilos, various; kyttasos, comb] (ARTHRO: Insecta) A type of nest of Vespidae in which the point mutation Intragenic mutation in which recombination is layers of brood comb are supported by the outer covering not impaired. and a central support, as the limb of a tree, sometimes re- poiser see halter garded as a group Poecilocyttares. see phragmocyttar- poison glands 1. (ARTHRO: Insecta) a. In Apocritan Hymen- ous. optera, modified accessory reproductive glands associated poecilogeny n. [Gr. poikilos, various; gennaein, to produce] with the ovipositor or sting. b. In Lepidoptera larvae, epi- (ARTHRO: Insecta) In Diptera, larval polymorphism with dermal glands associated with setae or spines. 2. (MOLL: more than one form, some being paedogenic and others Cephalopoda) The posterior salivary glands. developing normally into winged sexual adults. poison sac see venom gland poecilogony n. [Gr. poikilos, various; gonos, progeny] 1. De- poison seta 1. (ANN: Polychaeta) Elongate pungent chitinous velopment in certain invertebrate animals of the same spe- bristles that project from the parapodia, may be hollow and cies producing two kinds of young, although the adults are 704 705 Maggenti and Gardner On line Di ctio nar filled with fluid, contain retrorse spinules along the staff, or pollex n. [L. pollex, thumby]of1. The thumb. 2. (ARTHRO: In- Inv be needlelike in appearance. 2. (ARTHRO: Insecta) Hollow secta) In Lepidoptera, a fingere-rltieke process at the anal an- bra seta through which they discharge an irritating secretion gle of the cucullus of Noctuidae. 3t.e Z(ARTHRO: Crustacea) ool from the venom glands. see fixed finger. ogy polar body A minute, functionless cell produced and discarded polliniferous, pollinigerous a. [L. pollen, fine flour; ferre, to during the development of an oocyte. carry] Pollen bearing; formed for collecting pollen. polar cap (MESO) The eight anterior cells in the nematogen. pollinose a. [L. pollen, fine flour; -osus, full of] Covered with a polar field/plate (CTENO) One of two long ciliated depressions powdery coating. in the floor of the statocyst. polyact n. [Gr. polys, many; L. actum, deed] (PORIF) A megas- polarity n. [L. polus, axis] The condition of having opposite clere spicule with many rays diverging from a central focus. poles or qualities. polyadenous cercaria (PLATY: Trematoda) Cercaria with a polarization n. [L. polus, axis] 1. A potential difference across stylet and paired groups of penetration glands. a membrane. 2. Light that is filtered to vibrate in one plane polyandric a. [Gr. polys, many; aner, male] (ANN: Oli- only. gochaeta) Having testes in more segments than x-xi. polar plates 1. (CNID) Balance organs of two narrow ciliated polyandry n. [Gr. polys, many; aner, male] Females that mate bands in the transverse plane. 2. (CTENO) see polar with more than one male. polyandrous a. field/plate. polyarthric see multiarticulate polar ray see astral ray polyaxon n. [Gr. polys, many; axon, axle] (PORIF) Spicules polian tubules/villi see contractile tubules with several equal rays radiating from a central point. Polian vesicles (ECHINOD) In Holothuroidea and Asteroidea, polybasic a. [Gr. polys, many; basis, base] 1. Having more elongated sacs in the coelom that open into the ring canal than one base. 2. Genera originated on a number of spe- and function as expansion chambers. cies. polian vessel see contractile vessel polycentric a. [Gr. polys, many; kentron, point] Having sev- pollen basket see corbicula eral growth centers or centromeres. pollen brush/comb see scopa Polychaeta, polychaetes n.; n.pl. [Gr. polys, many; chaite, hair] The largest and very diverse class of the Phylum An- pollen pocket (ARTHRO: Insecta) In Hymenoptera, a reservoir nelida; commony called bristle worms, widely distributed for pollen beside a cell in some species of bumblebees; lar- throughout the marine environment. vae and adults have free access to the pollen. polychromatic a. [Gr. polys, many; chroma, color] Having pollen pot (ARTHRO: Insecta) In Hymenoptera, soft cerumen many colors. container used to store pollen by stingless bees; larvae do not have direct access to the pollen. polydelphic a. [Gr. polys, many; delphys, womb] (NEMATA) Having more than four uteri. pollen rake (ARTHRO: Insecta) In Hymenoptera, a comblike row of bristles at the apex of the hind tibia of a bee; a polydisk, polydisc n. [Gr. polys, many; diskos, disc] (CNID: pecten. Scyphozoa) The process of several ephyrae developing simultaneously, the most mature at the distal end. see pollen storers (ARTHRO: Insecta) In Hymenoptera, bumble- monodisk, strobilation. bees that temporarily store pollen in abandoned cocoons. 706 707 Maggenti and Gardner On line Di ctio nar polydiverticulate a. [Gr. polys, many; L. diverticulum, digres- thousand. y of Inve sion] (ANN) Referring to spermathecae with more than two polyhedron n.; pl. -dra [Gr. polys,rtmebany; hedros, side] Many- rate diverticula. sided; many angled; a solid having mZoaony faces. polyhe- log polydomous a. [Gr. polys, many; domos, house] Inhabiting dral a. y many abodes or nests. see monodomous. polykaric a. [Gr. polys, many; karyon, nut] Multinucleate. polyembryony n. [Gr. polys, many; embryon, fetus] The for- polylectic a. [Gr. polys, many; lektos, chosen] (ARTHRO: In- mation of multiple embryos from a single egg. polyem- secta) In Hymenoptera, species of bees that take pollen bryonic a. from a wide variety of plants. polyethism n. [Gr. polys, many; ethisma, habit] (ARTHRO: In- polyloculate a. [Gr. polys, many; L. loculus, small room] secta) In social insects, the division of labor among mem- (ANN: Oligochaeta) Having several seminal chambers in the bers of a colony. see age polyethism, caste polyethism. spermathecal diverticulum. polygamy n. [Gr. polys, many; gamein, to marry] Polygyny polymer n. [Gr. polys, many; meros, part] A large molecule and/or polyandry. polygamous a. see monogamy. made up of several to many smaller units called mono- polygenes n.pl. [Gr. polys, many; pan, all; gennaein, to pro- mers. duce] Genes that jointly, with a group of other genes, con- polymeric a. [Gr. polys, many; meros, part] Gene interaction trol a character. polygenic a. see oligogene. in which genes of equivalent effect intensify each others polygenic a. [Gr. polys, many; genos, descent] Dependent on effect. the interaction of genes; polygenetic. see monogenic. polymerization n. [Gr. polys, many; meros, part] Formation polygigeriate a. [Gr. polys, many; L. gigerium, gizzard] (ANN) of polymers from monomers. Having several gizzards. polymorph n. [Gr. polys, many; morphos, shape] 1. An indi- polygonadal a. [Gr. polys, many; gone, seed] (ANN) Having vidual within a species exhibiting a change in shape, color more than four gonads. or structure. 2. (BRYO) A zooid that differs from feeding zo- polygonal a. [Gr. polys, many; gonia, angle] Having many an- oids of the same stage of development; specialized zooid. gles, many sides; more than 4 sided. polymorphic, polymorphous a. [Gr. polys, many; morphe, polygoneutism n. [Gr. polys, many; gennaein, to produce] form] Having many forms or types of structure in the same The ability to produce several broods in one season. poly- species. goneutic a. polymorphism n. [Gr. polys, many; morphe, form] 1. The si- polygyny n. [Gr. polys, many; gyne, female] 1. The mating of multaneous occurrence of two or more distinctive and dis- a male with more than one female. see monogamy. 2. continuous genetic types existing in a population. 2. (AR- (ARTHRO: Insecta) In Hymenoptera, the coexistance of sev- THRO: Insecta) In social insects, the coexistence of two or eral to many queens in the same colony. a. Primary poly- more phases or castes, belonging to the same sex, within gyny: Two or more queens found a colony together. b. an individual colony. a. In Formicidae, the occurrence of Secondary polygyny: One queen founds a colony with oth- nonisometric growth of size variation in a normal mature ers added after the colony is founded. polygynous a. colony, thus producing individuals of distinctly varying pro- portions. 3. (BRYO) Repeated, discontinuous variation in polygyral see multispiral zooid morphology in a colony. polyhaline a. [Gr. polys, many; hals, sea] Pertaining to brack- polymyarian n. [Gr. polys, many; mys, muscle] (NEMATA) ish water of a wide range of salinities; 16 to 30 parts per 708 709 Maggenti and Gardner On line Di ctio nar Muscle arrangement in which there are many cells between polypidom see polypary y of Inve adjacent hypodermal cords. polymyarial a. see mero- Polyplacophora, polyplacophorarntenb. [Gr. polys, many; plax, rate myarian. tablet; phora, producing] A class of Zforoee-living mollusks log polynemic a. [Gr. polys, many; nema, thread] Chromosomes commonly referred to as chitons or coat-yof-mail shells; with a primarily multistranded structure, not the result of distinguished by having a shell with 8 dorsal calcareous endoreduplication. plates that overlap each other; in some classifications listed polyp n. [Gr. polys, many; pous, foot] (CNID) Any colonial or as the class Amphineura. solitary attached individual. polyploid a. [Gr. polys, many; aploos, onefold] Referring to an polypalmate a. [Gr. polys, many; palma, palm] (BRACHIO) A individual having more than two sets of chromosomes. see mantle canal system with more than 4 principal canals in chromosome. each mantle. polyploidy n. [Gr. polys, many; aploos, onefold] A condition in polypary n.; pl. -ies [Gr. polys, many; pario, to beget] (CNID: which the chromosome sets in the nucleus are a multiple of Hydrozoa) Structure/tissues in which the polyps of corals the normal diploid number. and other compound forms are embedded; polypidom; polypneustic a. [Gr. polys, many; pneustikos, of breathing] polyparium. (ARTHRO: Insecta) Having at least 8 functional spiracles on polyphagous a. [Gr. polys, many; phagein, to eat] Feeding on each side, including the holopneustic, peripneustic, hemip- many kinds of food. polyphagia n. neustic. polyphagy see polyphagous polypneustic lobes see respiratoria, respiratory plates polyphenism n. [Gr. polys, many; phaneros, visible] The oc- polypod larva (ARTHRO: Insecta) 1. An insect larval stage currence in a population of several phenotypes that are not found in Lepidoptera and some Hymenoptera with thoracic due to genetic differences between individuals; polypheny. appendages and caterpillar-like abdominal locomotory processes (prolegs); polypodeiform; eruciform larva. see polyphenol layer A silver binding product exuded from the tip protopod larva, campodeiform larva. 2. In parasitic of the pore canals, formerly considered as a sublayer in the Hymenoptera, it has many different forms, often unlike a epicuticle. normal insect. polyphyletic a. [Gr. polys, many; phyle, tribe] 1. Of mixed polypodous a. [Gr. polys, many; pous, foot] Having many evolutionary origin, not derived from a common ancestor. feet. see protopod, oligopod. 2. Pertaining to a group whose most recent common ancestor is not cladistically a member of that group. 3. Pleo- polypoid see polyp phyletic. polyphyly n. see monophyletic, oligophyletic. polyprostatic a. [Gr. polys, many; prostates, stands before] polyphyly see polyphyletic (ANN: Oligochaeta) Having more than six prostates in three segments or over eight in two segments. polypide n. [Gr. polys, many; pous, foot] (BRYO) The living portions of the zooid. polysaccharides n.pl. [Gr. polys, many; L. saccharum, sugar] A carbohydrate, one molecule of which can yield by hy- polypidian bud (BRYO) A newly developing polypide of a de- drolysis, many monosaccharide molecules, usually struc- veloping zooid. tural or storage, such as chitin, cellulose, starch and glyco- polypidian vesicle (BRYO) A polypidian bud, double-layered, gen. with an undifferentiated internal epithelium lined central polysaprobic a. [Gr. polys, many; sapros, putrid] Referring to cavity. 710 711 Maggenti and Gardner On line Di ctio nar a body of water with high decomposition rate and very low see oligotrophic. 2. Hayvionfg many trophi. Inve oxygen. polytrophic ovariole (ARTHRO: Inrstebcta) An ovariole in which rate polysiphonous a. [Gr. polys, many; siphon, tube] (CNID: Hy- trophocytes accompany each oocyteZooand are enclosed log drozoa) Pertaining to a hydrocaulis covered by stolons from within the follicle; a polytrophic egg tube. ysee meroistic the hydrorhiza. see monosiphonous. ovariole. polysomatic a. [Gr. polys, many; soma, body] Tissues or indi- polytropic a. [Gr. polys, many, tropikos, a turning] (ARTHRO: viduals having both diploid and polyploid cells. Insecta) Visiting many kinds of flowers for nectar. see polysome n. [Gr. polys, many; soma, body] A multiribosomal monotropic, oligotropic. structure consisting of ribosomes bound by messenger polytypic a. [Gr. polys, many; typos, type] A taxon containing RNA; very active in protein synthesis. subordinate units. polysomic a. [Gr. polys, many; soma, body] A diploid cell with polyvoltine see multivoltine one or more chromosomes represented three or four times, polyxenic a. [Gr. polys, many; xenos, guest] The rearing of instead of two. one or more individuals of one species in association with polyspermy n. [Gr. polys, many; sperma, seed] Entry of sev- many other known species of organisms. see dixenic, ax- eral sperm into the ovum. enic, synxenic, trixenic, xenic. polystichous a. [Gr. polys, many; stichos, row] Arranged in Polyzoa, polyzoan see Bryozoa many rows; multifarious. polyzoarium see zoarium polystomate, polystomatous a. [Gr. polys, many; stoma, polyzoic a. [Gr. polys, many; zoon, animal] (PLATY: Cestoda) mouth] 1. Having many mouths. 2. (ANN: Oligochaeta) Strobila consisting of more than one proglottid. Referring to nephridia with several nephrostomes. ponderous a. [L. pondus, weight] Of great weight; large; polytene chromosomes Giant chromosomes. see band. huge, bulky. polytesticulate a. [Gr. polys, many; L. testiculus, small testi- pons n. [L. pons, bridge] A bridge; structure connecting two cle] (ANN: Oligochaeta) Having more than two pairs of tes- parts. tes. pons cerebralis see protocerebral bridge polythalamous gball (ARTHRO: Insecta) In Hymenoptera, a chalcid gall containing more than one larval cell. population n. [L. populus, people] A group of individuals, especially with reference to numbers and statistics. polythecal a. [Gr. polys, many; theke, case] (ANN: Oli- gochaeta) Earthworm having more than one or two pair of population density The number of a group of individuals as to spermathecae per segment. see monothecal. unit area or volume. polythetic a. [Gr. polys, many; tithenai, to place] Referring to population, local The individuals of a potentially interbreeding a classification with each member of a group having the community. see deme. majority of a set of characters. see monothetic. porate a. [Gr. poros, channel] Bearing pores. polytopic a. [Gr. polys, many; topos, place] Occurring in sev- porcate a. [L. porca, ridge between two furrows] With longitu- eral geographical locations. dinal ridges and furrows. polytrophic a. [Gr. polys, many; trophein, to feed] 1. Having porcellaneous, porcelanous, porcelaneous a. [It. porcel- nutrition supplied from more than one organism or source. lana, procelain] Resembling porcelain; an enameled-like 712 713 Maggenti and Gardner On line Di ctio nar surface; a nacreous luster. bearing a pore. y of Inv erte pore n. [Gr. poros, channel] A minute opening or orifice; porose a. [Gr. poros, channel] Contabinraing pores; porous; per- te Z ostium. forate. ool ogy pore canals 1. (ARTHRO: Insecta) Flat or ribbon-like twisted porose area (ARTHRO: Chelicerata) Depressed areas on the channels of the procuticle, running through it perpendicu- capitulum of certain mites and ticks. larly to its surface. 2. (ARTHRO: Crustacea) In Ostracoda, a porphyrins n.pl. [Gr. porphyra, purple] Four pyrrole rings as- small tubular passageway extending through the shell. sociated with various metals forming chlorophyll, hemoglo- pore cells see porocytes bin, etc. pore-chambers (BRYO) Small chambers where new zooids are porrect a. [L. por, before; regere, to stretch] Elongated for- budded in the angles between the lateral and basal walls ward; stretched out horizontally. that are connected to the intrazooidial pores. portal of entry Point at which the invading parasite enters the pore diaphragm (PORIF) The closure of the porocyte. body of an animal; through either natural or unnatural pore plates 1. (ARTHRO: Insecta) In the soft scale Towmeyella openings. parvicornis , groups of invaginated, biocular pores on the position effect The difference in the phenotypic expression of dorsal surface of the derm. see sensilla placodea. 2. a gene due to a change in their position with respect to (BRYO: Gymnolaemata) An interior chitinous or calcareous other genes on the chromosome. wall of a zooid with one or more minute pores through positive geotropism Attraction toward the center of the which special cells project; part of the communication or- earth. gan. positive tropism/taxis The tendency to be attracted to a pore space The insterstice between soil particles. source of stimulus. Porifera n. [Gr. poros, channel; L. ferre, to bear] Phylum of postabdomen n. [L. post, after; abdomen, belly] 1. (ARTHRO) aquatic animals commonly called sponges; lacking organ- The usually slender, modified posterior segment of the ab- ized tissues and a digestive cavity. domen of Crustacea and Insecta. 2. (ARTHRO: Chelicerata) poriferous a. [Gr. poros, channel; L. ferre, to bear] Having The anal tubercle in spiders; in scorpions the metasoma or numerous openings. posterior narrower five segments of the abdomen. see tel- poriform a. [Gr. poros, channel; L. forma, shape] Resembling son. a pore; poroid. postacrostichal bristles see acrostichal bristles porocalyx n. [Gr. poros, channel; kalyx, cup] (PORIF: postalar a. [L. post, after; ala, wing] (ARTHRO: Insecta) Behind Demospongiae) In some Spirophorida, a specialized, the wings. sunken, inhalant and exhalant aperture. postalar arm (ARTHRO: Insecta) An extension behind the wing porocyte n. [Gr. poros, channel; kytos, container] (PORIF) in many insects, connecting the postnotum to the Pinacocytes enclosing a pore that functions as an inhalant epimeron; postalar bridge; postalare. see prealar arm. canal. postalar bridge see postalar arm poroid a. [Gr. poros, channel; eidos, like] Pore-like; poriform. postalar bristles (ARTHRO: Insecta) In Diptera, bristles on the porophore n. [Gr. poros, channel; phorein, to carry] (ANN: postalar callus. Oligochaeta) Any area, protuberance or special structure posticum see apopore 714 715 Maggenti and Gardner On line Di ctio nar postalar callus (ARTHRO: Insecta) In Diptera, the prominent gland cells are found. y of Inv posterodorsal angle of the scutum. erte postcoxal bridge (ARTHRO: Insecta) bTrhae post coxal part of the te Z postalar declivity see postalar wall thoracic pleuron, often united with the osotel rnum behind the ogy postalare see postalar arm coxa. postalar tail (NEMATA: Secernentea) That segment of the tail postembryonic a. [L. post, after; Gr. embryon, fetus] Per- posterior to the leptoderan bursa or caudal alae. taining to the life stage succeeding the embryonic. postalar wall (ARTHRO: Insecta) In Diptera, the ventrolateral postepipleurite see surpedal area surface below the postalar ridge; postalar declivity. posteriad adv. [L. post, after; -ad, toward] Directed backward, postanal plate see telson as opposed to anteriad. postantennal organ (ARTHRO: Insecta) In some Collembola, a posterior a. [L. posterior, latter] 1. Situated behind; behind variously shaped structure (ring-like, rosette, or complex), the axis. 2. (MOLL: Bivalvia) Direction along the major axis immediately behind the antennal bases; comprised of in which the anus faces and the exhalant current flows. sense-cell and several enveloping cells, possibly functioning posterior apophysis (ARTHRO: Insecta) In female Lepidoptera, as a chemorecepter. sclerotized, paired apodemes of the 8th abdominal seg- postapical a. [L. post, after; apex, the tip] (MOLL: Bivalvia) ment, extending cephalad and serving for muscle attach- Referring to lateral teeth situated behind the umbo or ment; apophyses posteriores. apex. posterior area (MOLL: Bivalvia) Area on the surface of the postbasal a. [L. post, after; Gr. basis, a pedestal] Behind; be- valve posterior to the posterior ridge. yond; near the base. posterior bulb see esophageal bulb postbascillary eyes (ARTHRO: Chelicerata) In Arachnida, the posterior callosity see postalar callus anterior median eyes that have the retinal nuclei behind posterior cardiac lobe see intestinal region the light-sensitive rods. see prebascillary eyes. posterior carina see intestinal region postcerebral glands see cephalic salivary glands posterior cell (ARTHRO: Insecta) In Diptera, one of the wing postclypeus n. [L. post, after; clypeus, shield] (ARTHRO: In- cells extending to the hind margin, between the third and secta) In some insects, the posterior or upper division of sixth longitudinal veins. the clypeus differentiated by a suture from the anteclypeus, the ginglymus of the mandible attaches here; posterior cephalic foramen see foramen magnum nasus; prefrons. see anteclypeus. posterior cribellum (ARTHRO: Chelicerata) In Arachnida, the postcolon n. [L. post, after; colon, colon] (ARTHRO: Chelicer- posterolateral spinnerets in Stenochilidae. ata) Region of the gut between the colon and the rectum in posterior cross vein (ARTHRO: Insecta) In Diptera, a wing certain mites. cross vein at the apex of the discal cell. postcornu n. [L. post, after; cornu, horn] (ARTHRO: Insecta) In posterior flange (MOLL: Bivalvia) In oysters, the flange poste- Hymenoptera, a single, supra-anal, sclerotized caudal spine rior to the left valve separated from the main body of the of Symphyta larvae. valve by the posterior radial groove. postcorpus n. [L. post, after; corpus, body] (NEMATA) The posterior gastric pit (ARTHRO: Crustacea) In Decapoda, one posterior part of the esophagus in which the esophageal of two small dorsal depressions midline on the exterior of 716 717 Maggenti and Gardner On line Di ctio nar carapace identifying the point of insertion of the stomach posterodorsal margin (MOyLLo:f Bivalvia) The margin of the dor- Inve muscle. sal part of the shell posterior tortehbe beaks. rate posterior lateral tooth (MOLL: Bivalvia) In heterodonts, the posterolateral a. [L. posterus, following;Zolaotus, side] Posteri- log lateral tooth situated posterior to the beaks and ligament. orly and toward the side. y posterior notch (MOLL) An indentation in the outer lip near the postesophageal commissure (ARTHRO: Insecta) The commis- suture. sure that joins the tritocerebral lobes of the brain and posterior orbit (ARTHRO: Insecta) In Diptera, part of the head passes beneath the stomodeum; tritocerebral commissure. behind the eyes. postesophageal loop (SIPUN) An extra loop in the foregut of posterior ridge (MOLL: Bivalvia) A ridge passing over or origi- species of Sipunculus and some Xenosiphon. nating near the umbo and running diagonally towards the post-fibers (ARTHRO: Crustacea) In Decapoda, giant nerve fi- posteroventral area of the valve. bers in crayfish that supply the deep parts of the abdominal posterior respiratory process (ARTHRO: Insecta) In Diptera, flexors and are responsible for escape reaction. see pre-fi- among Syrphidae larvae, caudal respiratory organ com- bers. posed of two fused tubes. postfrenum, postfroenum see postscutellum posterior sinus (MOLL: Polyplacophora) A recess in the poste- postfrons n. [L. post, after; furca, fork] (ARTHRO: Insecta) rior median line of a tail valve, formed by the tegmentum That portion of the frons posterior to the antennary base or in some forms by the articulamentum. line. posterior slope (MOLL: Bivalvia) The surface sector running postfrontal ridge (ARTHRO: Insecta) In Culicidae, an apodeme posteroventrally from the umbo of the valve. externally differentiated by the postfrontal suture. posterior spiracle (ARTHRO: Insecta) Spiracles on the caudal postfrontal suture (ARTHRO: Insecta) Facial sutures present segment or the most caudal pair of segments. occurring above the lateral ocelli and extending laterad of posterior spiracular plate (ARTHRO: Insecta) In Diptera, the the antennal bases. flattened tip of each tube that bears the posterior spiracles postfurca n. [L. post, after; furca, fork] (ARTHRO: Insecta) The of Syrphidae larvae. forked sternal process or apodeme of the metathorax. posterior stigmatal tubercle (ARTHRO: Insecta) In caterpil- postgena n.; pl. -ae [L. post, after; gena, cheek] (ARTHRO: lars, tubercles on the thoracic and abdominal segment. Insecta) A sclerite on the posterior lateral surface of the posterior tentorial arms (ARTHRO: Insecta) The apodeme head. postgenal a. extending anteriad from the posterior tentorial pits of the posthumeral bristle (ARTHRO: Insecta) In Diptera, one or head. more bristle(s) on the anterolateral surface of the posterior tooth (ARTHRO: Crustacea) In Decapoda, a midline mesonotum; near the inner edge of the humeral callus. carapace tooth between the posterior margin and the mar- postlabium see postmentum ginal groove. postlarval stage (ARTHRO: Crustacea) A developmental stage posterobiprostatic a. [L. posterus, following; bis, twice; Gr. after completion of the megalopal or equivalent metamor- prostates, stands before] (ANN: Oligochaeta) With refer- phosis, differentiated by appearance of adult characters. ence to male terminalia, prostates in segment xix after loss postmandibular area (BRYO) Membranous part of the frontal of a pair in segment xvii of an acanthodrilin set. wall on which the mandibular muscles insert. 718 719 Maggenti and Gardner On line Di ctio nar postmarginal vein (ARTHRO: Insecta) The fore wing vein along postpalmars n. [L. post, ayftoefr; palma, palm] (ECHINOD: Cri- Inve the anterior margin, beyond where the stigmal vein arises. noidea) Any brachials after the rtteerbtibrachs. rate postmentum n. [L. post, after; mentum, chin] (ARTHRO: In- postpectus n. [L. post, after; pectus, bZroeoast] (ARTHRO: In- log secta) A primary division of the labium; the basal portion, secta) The ventral surface of the metathorax.y proximad of the labial suture. postpedes see anal proleg post-mortem After death; post-mortem changes. postpedicel a. [L. post, after; pes, foot] (ARTHRO: Insecta) postnodal cross veins (ARTHRO: Insecta) A series of short The third segment of the antenna. wing cross veins behind the costal margin, between the postpeltidium see schizopeltid nodus and stigma. postpetiole n. [L. post, after; petiolus, little leg] (ARTHRO: In- postnotal plate see metapostnotum, mesopostnotum secta) 1. In Formicidae, the second segment of a two-seg- postnotum n.; pl. -ta [L. post, after; Gr. notum, back] (AR- mented pedicel. 2. In Ichneumonidae, where the petiole THRO: Insecta) The phragma-bearing plate in the dorsum of (first body segment) abruptly broadens near the spiracles. a pterothoracic segment, originating from the acrotergite of postphragma n. [L. post, after; Gr. phragma, fence] (ARTHRO: the following notum. see mesopostnotum, metapost- Insecta) 1. Internal plates developed from the antecostal notum. ridges at the front and back of the mesothorax and the postoccipital ridge (ARTHRO: Insecta) The internal aspect of back of the metathorax that provide attachment for the the postoccipital suture. large longitudinal muscles moving the wings. 2. In Diptera, postoccipital suture (ARTHRO: Insecta) The transverse suture a well developed phragma at the posterior extension of the on the head immediately posterior to the occipital suture, postnotum. and ending at the posterior tentorial pit on either side and postpudendum n.; pl. -da [L. post, after; pudenda, external along which are inserted the dorsal prothoracic muscles genitals of female] (NEMATA) The female genital tube that that move the head. proceed posteriorly from the vulva. postocciput n. [L. post, after; occiput, back of head] (ARTHRO: post-pygidial gland (ARTHRO: Insecta) In Formicidae, a gland Insecta) The extreme narrow posterior rim of the head, associated with the membrane between abdominal terga 7 between the postoccipital suture and the foramen mag- and 8, sometimes large; function unknown. see pygidial num. glands. postocellar area (ARTHRO: Insecta) In Hymenoptera, that part postreduction n. [L. post, after; reducere, to lead back] Re- on the dorsal aspect of the head bounded by the ocellar duction of the chromosome number to haploid in the sec- and vertical furrows and the caudal margin of the head. ond meiotic division. postocellar bristles see postvertical bristles postscutellum n. [L. post, after; dim. scutum, a shield] (AR- postocellar glands (ARTHRO: Insecta) In Hymenoptera, a THRO: Insecta) 1. A small transverse piece of a thoracic mass of glands situated above the ocelli in the drone and notum immediately behind the scutellum or between the queen bees; detached lobes of the cephalic salivary glands. apex of the scutellum and the base of the propodeum; pseudonotum. 2. In Diptera, a convex, transverse swelling postoral a. [L. post, after; os, mouth] Behind the mouth. below the scutellum; subscutellum. postorbital bristles (ARTHRO: Insecta) In Diptera, a row of postsegmental region see telson bristles behind and nearly parallel to the posterior of the eye. postsoma see metathorax 720 721 Maggenti and Gardner On line Di ctio nar poststernellum see spinasternum ing in meadows or bogs.y of Inv erte poststigmatal primary tubercle (ARTHRO: Insecta) In cater- preadaptation n. [L. pre, before; adbaraptatus, fitted] The poste Z pillars, a tubercle on the thorax. session of the necessary genotypic or phoeonl otypic properties ogy postsynaptic a. [L. post, after; Gr. synapsis, union] Pertaining that permit a shift into a new niche or habitat. to structures or events on the receiving side of a synapse. prealar arm (ARTHRO: Insecta) An extension in front of the posttriangular cells see discoidal cell wings connecting the prescutum with the pleuron; prealar bridge; prealare. see postalar arm. postuterine sac (NEMATA) A reduced, degenerate uterus non- functional in gamete production, usually posteriad to the prealar callus (ARTHRO: Insecta) In Diptera, a projection situ- vulva; may function as a storage organ for sperm in some ated just above the root of the wing. species. prealare see prealar arm postvertical bristles (ARTHRO: Insecta) In Diptera, a pair of preanal region see remigium bristles behind the ocelli, generally on the posterior surface preanal ring (ARTHRO: Diplopoda) Post-segmental ring ending of the head. trunk; usually has a tail, anal valves and scales; forms the postvulvar uterine branch see postuterine sac telson. potamoplankton n. [Gr. potamos, river; plankton, wandering] preapical a. [L. prae, before; apex, tip] Before the apex. Plankton of running water. preapical bristle (ARTHRO: Insecta) In Diptera, a bristle on the potential n. [L. potens, having power] In electrophysiology, outer border of the tibia, below the apex. the difference in charge between two points; usually in mil- preapical gland see phasmid livolts. preaxial a. [L. prae, before; axis, axle] On the anterior border pouch n. [OF. poche] 1. A small or moderate size receptacle, or before the axis. sac or bag. 2. (ARTHRO: Insecta) In Hymenoptera, the food holder for bumblebee larvae. 3. (CNID: Scyphozoa) An ex- preaxillary excision (ARTHRO: Insecta) In hind wings of Hy- tension of the stomach cavity. menoptera, a second notch of the apex of the first anal fold, just anterior of the first anal vein, in addition to the pouch-makers (ARTHRO: Insecta) Bumblebee species that axillary notch. build special pollen-filled pouches next to groups of their larvae. prebascillary eyes (ARTHRO: Chelicerata) In Arachnida, the anterior lateral, posterior lateral and posterior median eyes praecoxa n.; pl. -ae [L. prae, before; coxa, hip] (ARTHRO: that have the retinal nuclei in front of the light-sensitive Chelicerata) In arachnids, a term used instead of coxa in rods. see postbascillary eyes. some groups. prebasilare n. [L. prae, before; basis, base] (ARTHRO: Diplo- praesoma n. [L. prae, before; Gr. soma, body] (ACANTHO) The poda) In the gnathochilarium, a narrow transverse sclerite, proboscis, neck, and attached muscles and organs. just basal to the mentum. praniza n. (ARTHRO: Crustacea) In Isopoda, a parasitic larva of precardo n. [L. prae, before; cardo, hinge] (ARTHRO: Diplo- fishes in the suborder Gnathiidea. poda) The distal joint of a two piece cardo. prasinous a. [Gr. prasinos, leek green] Light green tending to precheliceral a. [L. prae, before; Gr. chele, claw; keras, horn] yellow; the color of a leek. (ARTHRO: Chelicerata) Anterior to the chelicerae; the acron pratinicolous n. [L. pratum, meadow; incola, inhabitant] Liv- and the three or four embryological segments anterior to 722 723 Maggenti and Gardner On line Di ctio nar the cheliceral segment; segment I. pre-epipod(ite) n. [L. praey,ofbefore; Gr. epi-, on; pous, foot] Inv (ARTHRO: Crustacea) The lateraerlltye directed lobe of the coxa. precibarium n. [L. prae, before; L. cibarius, pertaining to bra te Z food] (ARTHRO: Insecta) A canal formed by the union of the pre-episternum n. [L. prae, before; Gr.ooelpi-, on; sternon, ogy epipharynx and the hypopharynx, providing a connecting chest] (ARTHRO: Insecta) The anterior part of the epister- link between the food canal of the maxillary stylets and the num marked off as a separate plate. cibarial pump. prefemur see ischiopodite precipitin n. [L. praeceps, head long] A specific antibody de- pre-fibers n. [L. prae, before; fibra, fiber] (ARTHRO: Crusta- veloped in response to foreign protein in the blood. cea) In Decapoda, 4 giant nerve fibers in crayfish, 2 me- precocious stages 1. Premature development. 2. An organ dian making snaptic contact with the brain and with fibers that appears earlier in the development of a species than in from the anterior sense organs; 2 lateral ones are products the development of other related species. of the fusion of many cells. see post-fibers. preconnubia n. [L. prae, before; connubium, marriage] The preformation n. [L. prae, before; forma, shape] The archaic coming together of animals before mating season. theory that the egg (or sperm or zygote) contains a pre- precornua n. [L. prae, before; cornu, horn] (ARTHRO: Insecta) formed adult in minature, and only nourishment is required In Diptera larvae, the cornua of the cephalo-basipharynx. during development. precosta n. [L. prae, before; costa, rib] (ARTHRO: Insecta) In prefrons see postclypeus some primitive forms, the small first wing vein. pregula n. [L. prae, before; gula, throat] (ARTHRO: Insecta) In precoxa n. [L. prae, before; coxa, hip] 1. (ARTHRO: Crustacea) larval Coleoptera, the anterior section of the gular plate, in When present, the segment of the protopod proximal to the front of a median gular suture in hydrophilid, staphylinid, coxa; pleuropod. 2. (ARTHRO: Insecta) see subcoxa. pre- etc. coxal a. prehalteres n.pl. [L. prae, before; Gr. halter, weight] (AR- precoxal bridge (ARTHRO: Insecta) That part of the thoracic THRO: Insecta) In Diptera, the squamae. pleuron anterior to the trochantin, usually continuous with prehensile a. [L. prehendere, to seize] Adapted for grasping or the episternum and the basisternum; precoxale. holding; formed to coil around or cling. precursor n. [L. prae, before; currare, to run] 1. Element or prehensile spines see grasping spines substance that preceeds the final one. 2. Ancestor or an- preimago n. [L. prae, before; imago, image] (ARTHRO: In- cestral part. see anlage, rudiment. secta) The last phase of pupal stage when the adult struc- precursory cell A mother cell or metrocyte. tures are seen within the pupal covering. preimaginal a. predaceous, predacious a. [L. preda, prey] Having the char- preischium n. [L. prae, before; Gr. ischion, hip] (ARTHRO: acteristics of a predator. Crustacea) When present, the segment of the endopod predator n. [L. praedator, plunderer] An animal that kills or between the protopod and the ischium. renders its prey insensible in order to mostly or entirely prelarva n. [L. prae, before; larva, mask] (ARTHRO: Chelicer- consume it. ata) In Acari with a four stage development, the first predictive value The capability of a classification to make pre- postembryonic stage usually occurring in the egg, but may dictions on newly employed characters or newly discovered be a non-feeding form after eclosion; prelarval phase. taxa. prelateral lobe (ARTHRO: Crustacea) In Stomatopoda, the proximal lateromarginal lobe of the telson. 724 725 Maggenti and Gardner On line Di ctio nar Pre-Linnaean name A name published prior to January 1, prephragma n. [L. prae, yboeffore; Gr. phragma, fence] (AR- Inve 1758, the starting date of zoological nomenclature. THRO: Insecta) In Diptera, a phrtreabgma at the anterior mar- rate premandibular suture 1. (ARTHRO: Chilopoda) A suture that gin of the mesonotum, often smaZllooor vestigial. see log rises posterior to the eyes, and extends transversely across phragma, postphragma. y the head. 2. (ARTHRO: Insecta) Known as the epicranial prepuce n. [L. prae, before; Gr. posthe, penis] 1. (ARTHRO: suture. Insecta) see preputium. 2. (MOLL: Gastropoda) In certain premental gutter (ARTHRO: Insecta) In Diptera, the median Pulmonata, an extension of the distal end of the penis dorsal longitudinal groove of the prementum (theca) that sheath. houses the fascicle (stylets); labial gutter; labial lumen. prepupa n.; pl. -ae [L. prae, before; pupa, puppet] (ARTHRO: premental setae (ARTHRO: Insecta) In odonatan nymphs, se- Insecta) Quiescent last larval instar before ecdysis to a tae on the prementum which are of taxonomic importance. pupa; not ordinarily representing a distinct morphological stage; propupa. see pharate. a. In Thysanoptera and male prementum n. [L. prae, before; mentum, chin] (ARTHRO: In- Coccidae, a morphological stage, a quiescent instar follow- secta) The distal part of a labium in which all the labial ing the last larval instar, followed by a second quiescent, muscles have their insertion. pupal instar. b. In Diptera, the third instar larva between premorse a. [L. prae, before; modere, to gnaw] Terminating pupariation and the larval-pupal apolysis. prepual a. abruptly, as if bitten or broken off; having blunt or jagged preputial a. [L. prae, before; Gr. posthe, penis] Of or pertain- termination. ing to the prepuce. prenymph n. [L. prae, before; nympha, bride] (ARTHRO: Cheli- preputial sac (ARTHRO: Insecta) An eversible sac(s) on the cerata) In Acari, a nonfeeding, quiescent stage in the life penis bearing a small toothed plate that grips the wall of cycle of Trombiculidae. the female vagina during copulation; vesica; genital sac. preocellar band (ARTHRO: Insecta) In Odonata, a darkly pig- preputium n. [L. prae, before; Gr. posthe, penis] The external mented stripe in front of the ocelli. covering of the penis. preoral cavity 1. The mouth cavity. 2. (ARTHRO: Chelicerata) prepygidium n. [L. prae, before; Gr. pyge, rump] (ANN: Poly- In Acari, the space between the lips anterior to the oral chaeta) An area of segment addition anterior to the py- commissures. gidium. preoral sting (ARTHRO: Crustacea) In Branchiura, a retractile prerectum n. [L. prae, before; rectus, straight] An identifiable piercing structure with a basal poison gland, between the section of the alimentary canal between the mesenteron maxillulae (suction discs). proper and the rectum. prerectal a. prepatent period The biological incubation period. prereduction n. [L. prae, before; reducere, lead back] The re- prepectal carina (ARTHRO: Insecta) In certain Hymenoptera, duction to haploid of the chromosome number in the 1st an area near the front of the mesothorax, traversing the meiotic division. mesosternum near the front, and continuing upward on presaepium n. [L. prae, before; sepes, fence] (ARTHRO: In- each side of the front part of the mesopleurum. secta) In larvae of the ant tribe Camponotini, the shallow prepectus n. [L. prae, before; pectus, chest] (ARTHRO: In- depression on the venter of some anterior abdominal secta) The differentiated anterior portion of the mesepis- somites; suggested to resemble the trophothylax of pseu- ternum, often forming a conspicuous plate on the lateral domyrmecinae larva. thorax between the pronotum and mesepisternum. prescutal ridge (ARTHRO: Insecta) The internal strengthening 726 727 Maggenti and Gardner On line Di ctio nar ridge formed by the prescutal sulcus. pod(ite). 2. (ARTHRO: Chyeolficerata) In Acari, a small, termi- Inv nal part of the tarsus with aenrteendoskeleton of two scle- prescutal sulcus (ARTHRO: Insecta) A transverse sulcus divid- bra rotized pieces articulating with the apteotZele. ing the notum into an anterior prescutum and a scutum. ool ogy prescutellar area (ARTHRO: Insecta) In Diptera, the median preungual process (ARTHRO: Crustacea) In Malacostraca, a posterior area of the scutum, situated between the acros- structure at the base of the dactyl of the 4th pereopod in tichal area and the scutellum; prescutellar space. Paguridae; thought to be sensory in function. prescutellar seta/bristles (ARTHRO: Insecta) In Diptera, seta preupsilon see sternal apophyses occurring in several rows on the anterior and/or lateral prevalence n. [L. prae, before; valens, to be strong] The total margins of the prescutellar area. number of cases of a particular disease at a particular time, prescutellum n. [L. prae, before; scutum, shield] (ARTHRO: in any given population. see incidence. Insecta) The sclerite nearest the head when, on the rare prevulvar setae (ARTHRO: Insecta) In Coccidae, large setae occasion, the upper part of the segment of the notum is di- found anterior to the vulva on abdominal segments 6, 7, 8. vided into 4 parts. prezoea n. [L. prae, before; zoe, life] (ARTHRO: Crustacea) A prescutum n. [L. prae, before; scutum, shield] (ARTHRO: In- newly-hatched postnaupliar larva covered by embryonic secta) The first subdivision of the notum, usually followed cuticle. by scutum and scutellum; the anterior division of the Priapulida, priapulids n.; n.pl. [Gr. Priapos, god of male fer- meso- or metanotum. tility] A phylum of burrowing, vermiform marine animals presegmental region see acron with a variety of protuberances that are used in taxonomy. presocial a. [L. prae, before; socialis, of companionship] (AR- primary n. [L. primus, first] First; original. THRO: Insecta) Applied to groups that display some degree primary bud (BRYO) A hollow outward expansion of the body of social behavior short of true social behavior. see subso- walls of the ancestrula. cial, parasocial. primary circlet (ECHINOD: Asteroidea) A ring of prominent os- presternum n. [L. prae, before; Gr. sternon, chest] (ARTHRO: sicles on the aboral surface. Insecta) The first subdivision of the eusternum, followed by the basisternum and sternellum. primary culture A culture started from cells, tissues, or organs taken directly from organisms; if then subcultured, it prestomal teeth (ARTHRO: Insecta) In Diptera, a row of teeth becomes a 'cell line'. protruded by the labella, by means of blood-pressure, to allow food particles to traverse the pseudotrachae. primary epithelium The blastoderm. presutural bristles (ARTHRO: Insecta) One or more thoracic primary denticle (ARTHRO: Crustacea) In barnacles, denticles bristles of Diptera, immediately in front of the transverse found on the sutural edges of the compartmental plate. suture on either side. primary fiber (PORIF: Desmospongiae) Fiber at right angles to presynaptic a. [L. prae, before; Gr. synapsis, union] Pertain- the surface; containing sand or debris taken up by the ing to structures or events before a synapse. sponge. pretarsus n. [L. prae, before; Gr. tarsos, flat of the foot] 1. primary homonym Each of two or more identical species- (ARTHRO) The terminal segment of the leg of various ar- group names that were proposed in combination with the thropods, usually consisting of the lateral claws (ungues), same generic name at the time of original publication. and one or more pad-like structures; dactyl; dactylo- primary host see definitive host 728 729 Maggenti and Gardner On line Di ctio nar primary intergradation An intermediate zone between two budded after larval metyaomf orphosis; differing from subse- Inve phenotypically different populations, developed in situ as a quent zooids. rteb rate result of selection. see secondary intergradation. primary zoological literature The liteZroaoture dealing with log primary iris cells see corneal pigment cells animals or zoological phenomena, not mereyly a listing of primary ligament (MOLL: Bivalvia) Original ligamental struc- names. ture consisting of periostracum, lamellar layer and fibrous primaxil n. [L. primus, first; axis, axle] (ECHINOD: Crinoidea) layers; not secondary additions such as the fusion layer. The first axillary arm; the axillary primibrach. primary ocelli see dorsal ocelli primibrachs n.pl. [L. primus, first; Gr. brachion, upper arm] primary/periodical pleometrosis (ARTHRO: Insecta) In social (ECHINOD: Crinoidea) All brachials of an unbranched arm; Hymenoptera, a colony founded by a group of queens, there are usually 2, the second of which is an axillary. however, after emergence of the first workers, all but one primibrachial a. female disperse. see secondary pleometrosis, tempo- primitive a. [L. primus, first] Ancestral; original form; primor- rary pleometrosis. dial. primary pigment cells see corneal pigment cells primitive streak see germ band primary reproductive (ARTHRO: Insecta) In Isoptera, the primogyne n. [L. primus, first; Gr. gyne, female] The primary queen or male termite derived from winged adults, that type female of a species. establish a colony. see adultoid reproductive, nymphoid primordial a. [L. primordialis, original] Original or primitive; reproductive, ergatoid reproductive. having the simplest and most underdeveloped character. primary riblet (MOLL: Bivalvia) In shells with various strength primordial soup The solution or suspension of organic mole- of riblets, the riblet appearing early in development and cules thought to have given rise to life. remaining stronger than later ones. primordial valve (ARTHRO: Crustacea) In Lepadomorpha and primary royal pair see primary reproductive Verrucomorpha Cirripedia, one of 5 chitinous plates of cyr- primary segmentation The segmental division of the body pid larvae. originating in embryonic metamerism. primordiotrichy n. [L. primordialis, original] The hypothetical primary setae (ARTHRO: Insecta) In Lepidoptera, setae with a theory of chaetotaxy of ancestral types. see atactotrichy. definite arrangement found on caterpillars in all instars. primordium n.; pl. -dia [L. primordialis, original] 1. The ori- primary sexual characters Gonads and associated ducts. gin; beginning. 2. The first cells that are identifiable as the primary shell layer (BRACHIO) Outer layer under the perio- beginning development of an organ or structure; anlage; stracum; deposited by columnar epithelium of the outer blastema; fundament. mantle lobe. principalia n.pl. [L. principium, foundation] (PORIF) Spicules primary somatic hermaphrodite see intersex constituting main skeletal framework. primary spicule (PORIF) A major structural megasclere. priodont a. [Gr. prion, saw; odous, tooth] (ARTHRO: Insecta) In Coleoptera, referring to male Lucanidae bearing small primary teeth (BRACHIO) The cardinalia or central teeth below mandibles. see amphidont, teleodont. the umbones. prionodont a. [Gr. prion, saw; odous, tooth] (MOLL: Bivalvia) primary zooid (BRYO: Gymnolaemata) In some Cheilostomata, With teeth developed transversely to the cardinal margin; the ancestrula or one to several zooids simultaneously 730 731 Maggenti and Gardner On line Di ctio nar similar to taxodont. cular end of the proboscyisofsheath that causes the probosci- Inve priority n.; pl. -ties [L. prior, former, superior] The principle des to evert. rteb rate that of two competing names for the same taxon (below proboscis pore (NEMER) An aperture throZouogh which the pro- log the rank of an infraorder) the validity is based on which boscis is everted; the rhynchostome. y was published first, either by date or page (when in the proboscis sheath (PLATY: Cestoda) In Trypanorhyncha, a tube same journal). into which the proboscides maybe retracted. prisere n. [L. primus, first; serere, to join] A primary sere; proboscis worm The Nemertea, also called ribbon-worms. complete natural succession of communities, from bare habitat to climax. see plagiosere. probursal a. [L. pro, before; bursa, purse] (PLATY: Turbellaria) In Tricladida, having the bursal stalk long and arching an- prismatic a. [Gr. prisma, prism] 1. In the shape of a prism; teriorly over the penis, so that the bursa lies anterior to the microscopically honeycombed; a needle-like prism struc- penis. see retrobursal. ture. 2. (MOLL: Bivalvia) Pertaining to a type of shell structure that consists of calcite or aragonite prisms. procephalic lobes (ARTHRO: Insecta) In embryology of the cephalic region, expansion of the neural ridges forming the proala n. [L. pro, before; ala, wing] (ARTHRO: Insecta) The future brain and divided into three neuromeres, known as anterior wing; fore wing. proto-, deuto- and tritocerebrum; procephalon. proandry n. [Gr. pro, before; aner, male] 1. Anterior pair of procercoid n. [Gr. pro, before; kerkos, tail; eidos, like] (PLATY: testes. 2. (ANN: Oligochaeta) Testes restricted to segment Cestoda) The metacestode developing from the onco- X or homoeotic equivalent. sphere, containing a body proper and caudal vestige of the probofossa see premental gutter oncosphere, the cercomere. see neotenic procercoid. probolae n.pl. [Gr. probolos, any projecting prominence] process n.; pl. processes [L. processus, proceed] A marked (NEMATA) Ornate cuticular structures often fringed and/or prominence, projecting part, or outgrowth. branched, of the labial or cephalic region. processi longi see bacilliform proboscides n.pl. [Gr. pro, before; proboskis, trunk] (PLATY: processus ventralis (ARTHRO: Crustacea) A process on the Cestoda) Four long, tentacle-like, retractable structures posterior or lower side of the pars media, variable in shape, with rows of hooks in the order Trypanorhyncha. armed with thick, short spines, small in size or deeply cleft. proboscidial fossa (ARTHRO: Insecta) In Hymenoptera, the proclinate a. [Gr. pro, before; klinein, to incline] Inclined for- deep groove on the under side of the head of bees, in ward or downward. which the proboscis is folded in repose. procoria a. [L. pro, before; corium, leather] (ARTHRO: Insecta) proboscipedia n. [Gr. proboskis, trunk; L. pes, foot] (ARTHRO: Referring to coria anterior to the prothorax. Insecta) The anomaly of a labellum maturing as a leg. procorpus n. [L. pro, before; corpus, body] (NEMATA: Se- proboscis n.; pl. proboscises [Gr. proboskis, trunk] 1. Any cernentea) In Tylenchida, the anteriormost cylindrical part extended trunk or beaklike sucking mouth parts of numer- of the esophagus, between the stylet and metacorpus (me- ous invertebrates, as of leeches, planarians, dipteran in- dian bulb). sects, nemertine worms, acanthacephalans, annelids and mollusks. 2. (ECHI) Muscular food gathering and respiratory procrusculus n.; pl. -culi [L. pro, before; crusculus, little leg] organ extending from the trunk near the mouth. (PLATY: Trematoda) One or more stumpy, locomotive appendages on the posterior of a redia. proboscis bulb (PLATY: Cestoda) In Tranypanorhyncha, mus- 732 733 Maggenti and Gardner On line Di ctio nar procryptic colors Imitative colors useful for concealment as a creted by the mantle edgy eo.f Inve protection against enemies. see Batesian mimicry, Mul- prodorsal dehiscence (ARTHRO: Crthebelicerata) In molting, the rate lerian mimicry. line of weakness following the abjugalZofuorrow between the log proctal see anal aspidosoma and prodosoma. y proctiger n. [Gr. proktos, anus; L. gerere, to bear] (ARTHRO: prodorsum n. [L. pro, before; dorsum, back] (ARTHRO: Cheli- Insecta) Anal portion of the 10th abdominal segment. cerata) The dorsal surface of the aspidosomal tagma; may proctodaeal, proctodaeum see proctodeum have one or two transverse furrows. proctodeal feeding (ARTHRO: Insecta) In Isoptera, a drop of prodrome n. [Gr. prodromos, preceding] A premonitory the contents of the rectal pouch being obtained from the symptom, indicating the initial stage of a disease. prodro- anus of another termite. see stomodeal feeding. mal a. proctodeal valve see pyloric valve produced a. [L. producere, to produce] Elongated; extended; projecting. production n. proctodeum n. [Gr. proktos, anus; hodos, way] (ARTHRO) The posterior ectodermal region of the alimentary canal; hind- proecdysis n. [Gr. pro, before; ekdysis, getting out of] gut; proctodaeum. Preparation for molting, especially in decapod crustaceans. proctostome n. [Gr. proktos, anus; stoma, mouth] The proeminent see prognathous "mouth" of Cnidaria and Turbellaria. proenchium n. [Gr. pro, before; enchos, spear] (NEMATA) Has procumbent a. [L. pro, before; cubare, to lean] Prostrate; been used for both prostome and mesostome. trailing; leaning forward. proepilobous a. [Gr. pro, before; epi, upon; lobos, projection] procurved a. [L. pro, before; curvare, to curve] (ARTHRO: Che- (ANN: Oligochaeta) The prostomium slightly indenting the licerata) In Arachnida, used to denote the curvature of the first segment. eyes when the lateral eyes are further forward than the proepimeron n.; pl. -mera [Gr. pro, before; epi, upon; median eyes. see recurved. meros, part] (ARTHRO: Insecta) The epimeron of the pro- procuticle n. [L. pro, before; cutis, skin] (ARTHRO) The thicker thorax. layer beneath the epicuticle consisting of endocuticle and proepisternum n.; pl. -sterna [Gr. pro, before; epi, upon; exocuticle that lends mass and strength to the cuticle; it sternon, chest] (ARTHRO: Insecta) The episternum of the contains chitin, sclerotin and also calcium carbonate and prothorax. calcium phosphate deposits in Crustacea. proepistome see interantennular septum prodehiscence n. [L. pro, before; dehiscere, to divide] (AR- profile n. [L. pro, before; filum, outline] An outline as seen THRO: Chelicerata) In Acari, molting in which the splitting from the side or lateral view. of the old cuticle occurs laterofrontally beside the frontal protuberance. profundal region In deep lakes from limnetic zone to bottom. prodelphic a. [Gr. pro, before; delphys, womb] (NEMATA) Uteri profuse a. [L. profusus, abundant] Abundant. parallel and anteriorly directed. see amphidelphic, progenesis n. [Gr. pro, before; genesis, origin] 1. Retention of monodelphic, didelphic, opisthodelphic. juvenile characters by precocious, sexually mature mor- prodissoconch n. [L. pro, before; dis, two; concha, shell] phologically juvenile stage. see paedogenesis. 2. (PLATY: (MOLL: Bivalvia) 1. The embryonic shell. 2. Early shell se- Trematoda) Larval reproduction. creted by the shell gland of the larva. 3. Later shell se- progenital a. [L. pro, before; gignere, to beget] (ARTHRO: 734 735 Maggenti and Gardner On line Di ctio nar Chelicerata) In Acari, referring to the area between the prohaptor n. [Gr. pro, befoyreo;f haptein, to fasten] (PLATY: Tre- Inv primary and secondary genital opening and to the secon- matoda) In Monogenea, the aenrterior adhesive and feeding bra dary opening itself. organs. te Z ool ogy progenital chamber (ARTHRO: Chelicerata) In Acari, the prohemocyte, prohaemocyte n. [Gr. pro, before; haima, chamber between the primary and secondary genital blood; kytos, container] (ARTHRO) A small, round, oval or opening of Acariformes. elliptical hemocyte with a relatively large nucleus and in- progenital lips (ARTHRO: Chelicerata) In Acari, paired sym- tensely basophilic cytoplasm that divides and gives rise to metrical valves that close the progenital chamber of many other types of cells; hemocytoblast; stem cell; urzellen. Acariformes. prolegs n.pl. [L. pro, before; ON. leggr, leg] (ARTHRO: Insecta) progenitor n. [L. pro, before; gignere, to beget] An ancestral The fleshy abdominal legs of larvae; false legs. species. proleucocyte see prohemocyte progeny n. [L. pro, before; gignere, to beget] Offspring; proleucocytoid see prohemocyte young. proliferation n. [L. proles, offspring; ferre, to bear] An in- proglottid n. [Gr. pro, before; glotta, tongue] (PLATY: Cestoda) crease in size due to budding or cell division. One complete unit of reproductive organs in a strobila; proliferation zone (ARTHRO: Diplopoda) The place where new usually corresponding to a segment. segments are formed; between last segment and telson. proglottis n.; pl. -ides [Gr. pro, before; glotta, tongue] prolobic a. [Gr. pro, before; lobos, lobe] (ANN: Oligochaeta) (PLATY: Cestoda) A proglottid. Referring to a prostomium demarcated from and without a prognathous a. [Gr. pro, before; gnathos, jaw] Having mouth tongue in the peristomium. parts directed forward. see hypognathous, opisthogna- prolymphocyte see prohemocyte thous. promentum n. [L. pro, before; mentum, chin] (ARTHRO: Diplo- progoneate a. [Gr. pro, before; gonos, offspring] Having the poda) A median sclerite in the gnathochilarium, anterior of genital opening in the anterior region of the body. see op- the mentum or stipites. isthogoneate. promerites n.pl. [Gr. pro, before; meros, part] (ARTHRO: Dip- prograde a. [Gr. pro, before; L. gradus, step] (ARTHRO: Cheli- lopoda) In male Julida, the eighth pair of body limbs used cerata) In spiders, having the dorsal surface of the leg up- in conjunction with the ninth pair of trunk legs (mesomer- permost. ite) to draw out the female vulva. progredientes n.pl. [L. progrediens, advancing] (ARTHRO: In- promesonotal suture (ARTHRO: Insecta) In Hymenoptera, the secta) In Adelgidae, nymphs of the third generation that transverse seam separating the pronotum from the soon develop into wingless agamic females. mesonotum of Formicidae. progressive provisioning The practice of feeding the young prometaphase n. [Gr. pro, before; meta, between; phasis, during their development. see mass provisioning. appearance] In meiosis and mitosis the stage at which the progynous a. [Gr. pro, anterior; gyne, woman] (ANN: Oli- chromosomes move to the equatorial plate. gochaeta) Having ovaries restricted to segment xii or a prominence n. [L. prominens, projecting] A raised, produced homoeotic equivalent. or projecting area. prominent a. prohaemocyte see prohemocyte promitochondrion n.; pl. -ria [Gr. pro, before; mitos, thread; 736 737 Maggenti and Gardner On line Di ctio nar chondros, grain] The possible precursor of a mitochondrion. areas of the posterior seyctoofr of the shell. Inv erte promotion n. [L. pro, before; motio, move] (ARTHRO: Insecta) propedes n.pl. [L. pro, before; pes,brfaoot] (ARTHRO: Insecta) te Z The movement of the coxa, resulting in protraction. The forelegs, or prolegs of larvae. ool ogy promyal passage (MOLL: Bivalvia) In oysters, the exhalant propeltidium n. [Gr. pro, before; dim. pelte, shield] (ARTHRO: water passage found between the adductor muscle and Chelicerata) In Arachnida, the covering of the prosoma, ex- mantle isthmus. cept for plates V and VI. pronotal comb (ARTHRO: Insecta) In Siphonaptera, the row of prophallus n.; pl. -li [Gr. pro, before; phallos, penis] (ARTHRO: strong spines on the posterior margin of the pronotum. Insecta) In Odonata, the penis in the floor of fenestra be- pronotum n. [Gr. pro, before; notos, back] (ARTHRO: Insecta) tween hamuli; sheath of penis. The dorsal sclerite of the prothorax. prophases n.pl. [Gr. pro, before; phasis, appearance] The pronucleus n. [L. pro, before; nucleus, kernal] The spermato- early stages of mitosis or meiosis. zoa and ova nucleus after maturation, prepared for fusion prophragma n. [Gr. pro, before; phragma, fence] (ARTHRO: to form a zygote nucleus. Insecta) The anterior dividing wall of cuticular material pronymph n. [Gr. pro, before; nymphe, pupa] (ARTHRO: In- connecting the pro- and mesothorax. secta) An individual enclosed in an embryonic cuticle which prophylaxis n.; pl. -laxes [Gr. pro, before; phylaktikos, is shed during eclosion and left in the egg shell, or cast af- guard] Methods designed to preserve health and prevent ter hatching; vermiform larva; primary larva. the spread of disease. pronymphal membrane Embryonic cuticle covering the pro- proplegma n.; pl. -ae [Gr. pro, before; plegma, plaited] (AR- nymphs with simple (hemimetabolus) or sometimes com- THRO: Insecta) A single fold of the proplegmatium. plete (holometabolus) metamorphosis, which are shed by a proplegmatium n.; pl. -ia [Gr. pro, before; plegma, plaited] process similar to molting before or shortly after hatching; (ARTHRO: Insecta) In scarabaeoid larvae, one of two areas embryonic cuticle; paraderm. with a plicate surface inside, usually in front of a plegma- proorchic a. [Gr. pro, before; orchis, testicle] (NEMATA) An tium; submarginal striae. anteriorly directed testis. propleural bristles (ARTHRO: Insecta) In Diptera, bristles situ- proostracum n. [Gr. pro, before; ostrakon, shell] (MOLL: ated on the propleuron; just above the coxae of the fore- Cephalopoda) The anterior prolongation of the rostrum; a legs. horny pen. see gladius. propleuron n.; pl. -pleura [Gr. pro, before; pleura, side] (AR- propagate v. [L. propagare, to propagate] 1. To transmit a THRO: Insecta) The lateral portion of the prothorax. wave of excitation along a nerve fiber. 2. To continue or propneustic a. [Gr. pro, before; pneustikos, of breathing] (AR- cause to multiply. THRO: Insecta) Having only the anterior pair of spiracles proparamere n. [Gr. pro, before; para, near; meros, part] open and functioning. see oligopneustic. (ARTHRO: Insecta) 1. In some Dermaptera, a lateral sclerite propodeal apophyses (ARTHRO: Insecta) In ichneumonid Hy- which may consist of anterior and posterior parts that sup- menoptera, the posterior transverse carina (apical carina) port the parameres. 2. In Diptera (Cyclorrhapha), one of with promontories at its junction with the lateral longitudi- two parameral processes. see opisthoparamere. nal carinae. proparea n. [Gr. pro, before; pareia, cheek] propodeon see propodeum (BRACHIO:Inarticulata) One of a pair of roughly triangular 738 739 Maggenti and Gardner On line Di ctio nar propodeum n. [Gr. pro, before; podeon, neck] (ARTHRO: In- The wall of the prostomey.osfee rhabdion. Inve secta) 1. In apocrite Hymenoptera the fused first abdomi- prosartema n. [Gr. pros, forward;rteabrtema, earring] (ARTHRO: rate nal segment; median segment; propodeon also used. see Crustacea) In Decapoda, a row of densZeoosetae on the inner log alitrunk. 2. For Formicidae, a synonym for epinotum. margin of the basal segment of the antennyular peduncle; propodite n. [Gr. pro, before; pous, foot; -ites, part] (ARTHRO) also called eye brush. 1. The next to last segment of a generalized limb. 2. (AR- proscolex n. [Gr. pro, before; skolex, worm] (PLATY: Cestoda) THRO: Insecta) The tarsus. 3. (ARTHRO: Crustacea) see The anterior part of a divided scolex. propodus. prosiphonate lining (PORIF: Calcarea) In recent Sphinctozoa, propodium n. [Gr. pro, before; pous, foot] (MOLL: Gastropoda) the lining of the atrial cavity of one chamber growing for- The foremost divison of the foot, functioning in pushing ward into the base of the next-youngest chamber. aside sediment as the animal crawls. prosochete n. [Gr. proso, forward; chetos, need] (PORIF) An propodosoma n. [Gr. pro, before; pous, foot; soma, body] inhalant canal that lead to chambers. (ARTHRO: Chelicerata) In Acari, the region of the podosoma that bears the first and second pairs of legs. prosocline a. [Gr. proso, forward; klinein, to slant] 1. (MOLL: Bivalvia) Hinge teeth or shell sloping anteriorly. 2. (MOLL: propodus n. [Gr. pro, before; pous, foot] (ARTHRO: Crustacea) Gastropoda) Usually referring to growth lines leaning for- The 4th segment of an endopod, between the carpus and ward (adapically) with respect to the direction of the heli- dactyl. cocone. propolar cells (MESO: Rhombozoa) In Dicymedia, the anterior prosocyrt a. [Gr. proso, forward; kyrtos, curved] (MOLL: Gas- tier of cells in the calotte. tropoda) Used to describe the growth direction of the heli- propolis n. [Gr. pro, before; polis, city] (ARTHRO: Insecta) In cocone curving forward. Hymenoptera, a term for resins and waxes collected by prosodus n.; pl. -i [Gr. prosodos, procession] (PORIF: Des- bees for use in construction and sealing crevices in the nest mospongiae) Tiny channels between the inhalant canal wall. system and exhalant canals. see aphodus. propped a. [ME. proppe, prop] (MOLL: Polyplacophora) Per- prosogyrate a. [Gr. proso, forward; gyros, a circle] (MOLL: Bi- taining to teeth of the valves having edges thickened on valvia) Describing beaks anteriorly directed; prosocoelous. the outside. prosoma n. [Gr. pro, before; soma, body] 1. (ARTHRO) The proprioceptor n. [L. proprius, ones own; receptor, receiver] 1. anterior part of the body, usually applied to the cephalo- Internal sense organs that lie within the body cavity and thorax. 2. (ARTHRO: Chelicerata) Fused imperceptably to respond to internal conditions of the organism. 2. Mech- the opisthosoma in Acari. see proterosoma. 3. (ARTHRO: anoreceptors that detect movements or position of the Crustacea) Commonly limited by the major articulation; in body parts; in arthropods, cordotonal organs, campaniform barnacles, large saclike body in position of head in front of, sensilla, and hair plates. and rostrad to, thoracic appendages; prosome. 4. (ARTHRO: propupa n. [L. pro, before; pupa, puppet] (ARTHRO: Insecta) Insecta) The head and the two succeeding fused segments The instar preceding the pupa in Thysanoptera and male of Coccoidea. prosomal a. Coccidae; sometimes also called prepupa. prosome n. [Gr. pro, before; soma, body] The anterior body propus see propodite region, specifically used in Phoronida.. see prosoma. prorhabdion n. [Gr. pro, before; rhabdion, little rod] (NEMATA) prosopon n. [Gr. proso, forward; ponos, work] (MOLL: Bival- 740 741 Maggenti and Gardner On line Di ctio nar via) The name proposed to replace surface ornament or projections of the prostoymoifum. Inv sculpture. erte prostomium n. [Gr. pro, before; stobmraa, mouth] 1. The ante- te Z prosopore n. [Gr. proso, forward; poros, channel] (PORIF) An rior preoral unsegmented portion of a soeogl mented animal's ogy aperture leading to a prosochete. body. 2. An acron. 3. (ANN: Oligochaeta) The anterior pro- prosopyle n. [Gr. proso, forward; pyle, gate] (PORIF) The tuberance above the mouth in the first segment; a preoral opening of the incurrent canal into the flagellated chamber; lobe. prostomial a. sieve area. protaesthesis n. [Gr. protos, first; aisthesis, sense] A primi- prostal n.; pl. -ia [L. pro, before; stare, stand] (PORIF) Spi- tive sensilla or sense-bud. cules that project from the sponge; marginal prostalia en- protamphibion n. [Gr. protos, first; amphibios, double life] circle the osculum; pleural prostalia are on the body sur- (ARTHRO: Insecta) The hypothetical common ancestor of face; basal prostalia form root or anchoring spicules. Plecoptera, Ephemeridae and Odonata. see protentomon. prostate/prostatic glands 1. (ANN: Oligochaeta) In earth- protandrous hermaphrodite A hermaphrodite that functions worms, atrial glands of unknown function. 2. (MOLL) An first as male and then transforms into female. see proto- elaboration of the sperm canal that secretes a prostatic gynous hermaphrodite. solution. 3. (NEMATA: Secernentea) A gland emitting an ad- protandry n. [Gr. protos, first; aner, male] 1. Maturation of hesive secretion at the distal end of the ejaculatory duct. 4. the male gonads, then of the female organs, within a her- (PLATY: Turbellaria) The spermiducal glands. maphroditic individual. 2. Males appear earlier in the sea- prosternal furrow (ARTHRO: Insecta) In many Reduviidae and son than females. protandrism n. see protogyny. Phymatidae in the Hemiptera, a cross-striated furrow; protaspis larva (ARTHRO: Trilobita) Larval period after emer- stridulation is produced by the rugose apex of the rostrum gence from the egg, covered by a single, dorsal carapace rubbing over it. and consisting of an acron and four postoral segments. see prosternal process, spine or peg (ARTHRO: Insecta) In Elat- meraspis larva. eridae Coleoptera, a process extending backward into the protease n. [Gr. proteios, primary; -ase, enzyme] Any prote- mesosternal cavity. olytic enzyme. prosternum n. [L. pro, before; sternum, breast bone] (AR- protective coloration/mimicry see cryptic colors, Bate- THRO: Insecta) The sternum, or ventral sclerite of the pro- sian mimicry, Mullerian mimicry. thorax. protective zooid or polyp see dactylozooid, tentaculozo- prostheca n. [Gr. pros, near; theke, case] (ARTHRO: Insecta) oid The small movable lobe-like process near the extremity of the mandible; the lacinia mobilis. protegulal node (BRACHIO) The apical area of the adult shell; site of protegulum and further growth to brephic stage. prosthetic group A non-peptide portion of an enzyme (may be organic or inorganic) that is responsible for the specific protegulum n. [L. pro, before; tegulum, roof] (BRACHIO) The biological action of the protein. see coenzyme, cofactor. embryonic shell of organic material secreted simultaneously by both mantles. prostome, prostom n. [Gr. pro, before; stoma, mouth] (NEMATA) The anterior subdivision of the protostome. see proteiform a. [Gr. Proteus, changing god; L. forma, shape] mesostome, metastome. Assuming different forms; variable. prostomial peaks (ANN: Polychaeta) Sclerotized antero-lateral proteins n.pl. [Gr. proteion, primary] Complex organic compounds of carbon, nitrogen, hydrogen, oxygen and often 742 743 Maggenti and Gardner On line Di ctio nar other elements, yielding amino acids by hydrolysis; essen- in two pairs of fully deyvoefloped wings in essentially larval Inve tial in cells of all plants and animals. (nymphal) or pupal in somatic drtifefberentiation. rate protelattosis n. [Gr. protos, first; elatton, smaller] (ARTHRO: prothoracic bristle (ARTHRO: Insecta) IZnooDiptera, a bristle log Chelicerata) In Acari, regression of the first instar, particu- above each of the front coxae. y larly regarding elattostase and calyptostase. prothoracic glands (ARTHRO: Insecta) Specialized endocrine protelean parasite A parasitic organism during larval or juve- glands of larvae consisting of a pair of diffused glands at nile stages and free-living as adult. the back of the head, the thorax, or at the base of the la- protentomon n. [Gr. protos, first; entoma, insect] (ARTHRO: bium producing the molting hormone (ecdysone); usually Insecta) A hypothetical organism suggested as the ances- breakdown after the final molt; thoracic glands; pericardial tral form of winged insects. see protamphibion. glands; ecdysial glands; ventral glands. proteolytic a. [Gr. proteios, primary; lysis, a loosing] Protein- prothoracic shield see cervical shield splitting. prothorax n. [Gr. pro, before; thorax, chest] (ARTHRO: In- proterandry see protandry secta) The first segment of the thorax, bearing the front legs, but no wings; manitruncus; corselet. prothoracic a. proterodehiscence n. [Gr. proteros, before; L. dehiscere, to divide] (ARTHRO: Chelicerata) In Acari, splitting of the old protobranchite n. [Gr. protos, first; branchiae, gills] (ARTHRO: cuticle in the anterior part of the body during molting. Insecta) Respiratory apparatus contained in the rectum of nymphal Odonata. see branchial basket. proterogenesis n. [Gr. proteros, before; genesis, origin] Young forms appearing similar to adult forms. protocephalon n. [Gr. protos, first; kephale, head] 1. (AR- THRO: Insecta) The procephalic part of the definitive head proterogyny see protogyny during evolutionary stages. 2. (ARTHRO: Crustacea) see ac- proterosoma n. [Gr. proteros, before; soma, body] (ARTHRO: ron. Chelicerata) In Acari, a combination of the gnathosoma and protocerebral bridge, (pons cerebralis) (ARTHRO: Insecta) A propodosoma; pseudotagma. median mass of neuropile of the protocerebrum, in the dor- Proterostomia n. [Gr. proteros, before; stoma, mouth] All sal and posterior part of the pars intercerebralis, connect- phyla in which egg cleavage is of the determinent type; in- ing with many parts of the brain. cludes all bilateral phyla except chaetognaths, pogonopho- protocerebral region (ARTHRO) That part of the primitive ar- res, hemichordates and chordates. thropodan brain containing the ocular and other association proterothesis n. [Gr. proteros, before; thesis, an arranging] centers. (ARTHRO: Insecta) In Hymenoptera, the laying of eggs by protocerebrum n.; pl. -bra [Gr. protos, first; L. cerebrum, certain solitary wasps and bees, which first produce fe- brain] (ARTHRO) The anterior, (in hypognathous insects males and then males. dorsal), most complex part of an arthropod brain consisting proterotype n. [Gr. proteros, before; typos, type] The original of three pair of optic centers and other neuropiles func- primary type, including all the material upon which the tioning in intergrating photoreception, movement and original description is based. thought to be centers for the initiation of complex behav- prothetely n. [Gr. pro, before; theein, to run; telos, comple- ior; the archicerebrum and prosocerebrum. protocerebral tion] 1. (ARTHRO) A neotenous adult arthropod having un- a. dergone less than the normal number of molts. see protocnemes n. [Gr. protos, first; kneme, wheel spoke] (CNID: metathetely, hysterotely. 2. (ARTHRO: Insecta) Resulting Anthozoa) In Zoanthinaria, the original 6 pairs of mesen- 744 745 Maggenti and Gardner On line Di ctio nar taries. areolets between the coysotaf l cells and the apical margin of Inve protocoel n. [Gr. protos, first; koilos, hollow] (BRYO) The an- the wings. rteb rate terior section of the coelomic cavity; in Phylactolaemata, protonephridium n. [Gr. protos, firstZ;oonephron, kidney] log assumed to be the cavity of the epistome. Nephridium having a flame cell or solenocytye at its proxi- protoconch n. [Gr. protos, first; konche, shell] (MOLL: Gastro- mal end; found in coelomate, pseudocoelomate and poda) The embryonic shell of a univalve, indicated by the acoelomate animals. apical whorls of the adult shell being clearly demarcated protonephromixium n. [Gr. protos, first; nephron, kidney; from later ones. see prodissoconch. mixis, mingling] A protonephridium that opens into the protocooperation n. [Gr. protos, first; cum, with; operari, to coelomoduct. see nephromixium. work] Interactions between 2 populations that is favorable protonymph n. [Gr. protos, first; nymphe, young woman] to both, but is not obligatory. (ARTHRO: Chelicerata) In Acari, the 1st stase of the nym- protocorm n. [Gr. protos, first; kormos, trunk] (ARTHRO: In- phal phase; in Mesostigmata, the early, bloodsucking stage secta) A long narrow 'tail' in the developing egg from which in the life cycle. the trunk segments of insects form; primary trunk region. protonymphon larva (ARTHRO: Chelicerata) In Pycnogonida, protocormic a. the 1st stage larva with 3 walking legs, with the mouth protodichthadiigyne n. [Gr. protos, first; dichthadios, double; anterior to the chelicera. gyne, woman] (ARTHRO: Insecta) In Doryline Hymenoptera, protoplasm n. [Gr. protos, first; plasma, formed or molded] a fertile intermediate between ergatoid and dichthadiigyne. Matter by which the phenomena of life are manifested. protogastric lobe/area (ARTHRO: Crustacea) In Decapoda, a protoplasmic a. median part anterior to the cervical groove and posterior to protoplast n. [Gr. protos, first; plastos, formed] The living the frontal region. part (protoplasm) of the cell covered by the cell mem- protogyne n. [Gr. protos, first; gyne, woman] A female that brane. resembles the male of the same species; a normal female. protoplax n. [Gr. protos, first; plax, flat plate] (MOLL: Bivalvia) see primogyne, deutogyne. In Pholadidae, simple, nearly flat, dorsal chitinous or cal- protogynous hermaphrodite A hermaphrodite that functions careous plate anterior to the umbo. see mesoplax, meta- first as a female and then transforms into a male. see plax. protandrous hermaphrodite. protopod n. [Gr. protos, first; pous, foot] (ARTHRO: Crustacea) protogyny, proterogyny n. [Gr. protos, first; gyne, woman] The part of an appendage, consisting of coxa and basis or 1. A condition of hermaphroditic individuals where the fe- precoxa, coxa, and basis, sometimes fused; protopod(ite); male sex organs are active before the male; proterogyny. sympod; sympodite. 2. Females appearing earlier in the season than males. see protopod(ite) n. [Gr. protos, first; pous, foot] (ARTHRO) The protandry. basal stalk of a segmented appendage; sympod or sympo- protolog, protologue n. [Gr. protos, first; logos, work] The dite. see protopod. original description of a scientific name. protopod larva (ARTHRO: Insecta) In some parasitic Hymen- protoloma n. [Gr. protos, first; loma, fringe] (ARTHRO: In- optera and Diptera, the earliest phase with segmentation secta) The anterior margin of the primaries or fore wings. absent or indistinct and with rudimentary appendages only on the head and thorax. see polypod larva, campodei- protomesal areolets (ARTHRO: Insecta) In Hymenoptera, form larva. 746 747 Maggenti and Gardner On line Di ctio nar protoscolex n. [Gr. protos, first; skolex, worm] (PLATY: ered ancestral. y of Inv Cestoda) In Taeniidae, a juvenile scolex budded within a erte prototergite n. [Gr. protos, first; L.brtaergum, back] (ARTHRO: hydatid or coenurus metacestode. te Z Insecta) The anterior dorsal segment ofotohle abdomen. ogy protosoma, protosome n. [Gr. protos, first; soma, body] 1. prototheca n. [Gr. protos, first; theke, case] (CNID: Hydrozoa) (ARTHRO) The prosoma. 2. (POGON) The anterior tentacular In corals, the surrounding walls of the calyx. region bearing 1-200 tentacles and including the principal nerve ganglion. see prosome. prototrichy n. [Gr. protos, first; thrix, hair] Chaetotaxy in which certain areas have only idionymous ancestral setae. protospecies n. [Gr. protos, first; L. species, kind] The preex- isting type from which other species evolved. prototroch n. [Gr. protos, first; trochos, wheel] The preoral girdle of cilia (first girdle) characteristic of a trochophore protostasy n. [Gr. protos, first; stasis, standing] (ARTHRO: larva. Chelicerata) In Acari, an orthostasic stage in a life cycle involving six stases. see orthostasy. prototrochophore larva A young trochophore larva with an apical organ, prototrochal girdle and a digestive tract with protosternum n. [Gr. protos, first; sternon, chest] (ARTHRO: mouth and anus. Chelicerata) In Acari, the sternite of the cheliceral segment of the prosoma. prototrochula larva (PLATY: Turbellaria) A free swimming larva of some Polycladida supposed to be a precursor of the protostome, protostom n. [Gr. protos, first; stoma, mouth] trochophore larva of other animals. 1. Metazoans with determinate spiral clevage and where the mesoderm can be traced to a single cell in the blastula, prototype n. [Gr. protos, first; typos, type] The original type the mouth originates from the blastopore; includes mol- species; the primitive or ancestral form. lusks, annelids, arthropods, nematodes and certain lesser protozoea n. [Gr. protos, first; zoe, life] (ARTHRO: Crustacea) phyla. see deuterostome. 2. (NEMATA) In rhabditid-like The postnaupliar substages in which the antennae and nematodes, the cylindrical midportion of the stoma, delim- some of the thoracic exopods are natatory. see zoea. ited anteriorly by the cheilostome and posteriorly by the protract v.t. [L. pro, before; tractus, a space drawn out] To telostome; the protostom may be further subdivided into: extend forward or outward; to protrude. prostome, mesostome and metastome. protractive see prosocline Protostomia n. [Gr. protos, first; stoma, mouth] Formerly the main division between bilateral animals, including the mol- protractor muscles 1. A contractile muscle that functions to lusks, annelids, and arthropods. extend an organ. 2. (NEMATA) Muscles attached to the stylet knobs or base and anteriorly to the body wall or head protostracum n. [Gr. protos, first; ostrakion, a shell] (MOLL: skeleton. 3. (SIPUN) In adult Xenosiphon and some larval Bivalvia) 1. In larval forms, the first formed part of a pro- forms, an extra pair of muscles attached to the introvert dissoconch. 2. In oysters, the shell of the D-shaped larval near the brain and to the body wall of the trunk anteriorly. stage; straight-hinge veliger. protractor preputii see hood protractor protostyle n. [Gr. protos, first; stylos, piller] (MOLL) The stiff mucous rod of early mollusks that transports the food protriaenes n.pl. [L. pro, before; Gr. triaina, trident] (PORIF) string along the esophagus into the stomach; the forerun- Tetraxons, with three clads directed forward making an an- ner of the crystalline style. gle of less than 45° with the produced axis of the rhab- dome. prototaxy n. [Gr. protos, first; taxis, arrangement] The arrangement of organs in certain areas that are all consid- protrusile a. [L. pro, before; trudo, thrust] Capable of being 748 749 Maggenti and Gardner On line Di ctio nar protruded or withdrawn. pruinescence n. [L. pruinyosouf s, frosty] (ARTHRO: Insecta) A Inv 'bloom' covering of whitish or weratexy particles. pruinose a. protuberance n. [L. protuberare, to swell] An elevation, knob bra te Z or prominence above the surface. Przibram's rule An empirical law of growotohl ; as the volume ogy prouterus see columella increases by the cube of a number, the area increases by the square; 1.26 or 3√2. proventricular valvule (ARTHRO: Insecta) In Diptera, a circular fold of the intestinal wall in Tipuloidea. psammon n. [Gr. psammos, sand] Freshwater or marine organisms living between sand grains; mesopsammon. proventriculus n.; pl. -li [L. pro, before; ventriculus, dim. of psammous a. venter, belly] An area of the foregut in annelids, insects and crustaceans just anterior to the midgut, and variously psammophilous a. [Gr. psammos, sand; philos, loving] Living modified for grinding or other uses; sometimes called giz- in or growing in sandy areas or sand; arenicolous. psam- zard. proventricular a. mophile n. provinculum n. [L. pro, before; vinculum, a binding] (MOLL: psammophore n. [Gr. psammos, sand; phoreus, bearer] (AR- Bivalvia) A primitive hinge consisting of very small teeth THRO: Insecta) In Formicidae, fringes of long hairs on the that develop before the permanent teeth are formed. posterior surface of the head. provisional mandibles (ARTHRO: Insecta) In some Coleop- pseudanal segment (ARTHRO: Chelicerata) In acariform Acari, tera, parts of the mandible found in the pupa, for escaping segment XIII and one of the paraproctal segments. the cocoon; imaginal cephalic cocoon-cutters. pseudaposematic/pseudoaposematic color Mimicry of col- proxagalea see subgalea oration or form of another organism possessing dangerous or disagreeable qualities; Batesian mimicry; allosematic proximad adv. [L. proximus, nearest; -ad, toward] Toward the color. see sematic. end or portion nearest the body. pseudarolium n.; pl. -olia [Gr. pseudos, false; arole, protec- proximal a. [L. proximus, nearest] 1. Toward or nearer the tion] (ARTHRO: Insecta) 1. A pad at the apex of the tarsus, place of attachment or reference of the center or midline of similar to an arolium. 2. In Miridae Hemiptera, a more lat- the body. 2. (BRYO) Toward the ancestrula. eral pair of processes present in some subfamilies at the proximal chiasma A chiasma between an inversion loop and bases of the claws. the centromere. pseudepipod(ite) n. [Gr. pseudos, false; epi, upon; pous, proximal gill wheal (MOLL: Bivalvia) In oysters, a low ridge foot] (ARTHRO: Crustacea) In Cephalocardia, the lateral (wheal) on the inner surface of the valve showing the lobe arising from the distal point of the exopod. proximal edge of the gills. pseudepisematic color Having mimicry coloration for attrac- proximal hemiseptum (BRYO: Stenolaemata) A hemiseptum tant or aggressive purposes. see episematic, sematic. projecting from the proximal zooid wall. pseudergate n. [Gr. pseudos, false; ergates, worker] (AR- proximal sensory area see haptolachus THRO: Insecta) In Kalotermes Isoptera, a larval form func- prozona n. [Gr. pro, before; zone, belt] (ARTHRO: Insecta) The tionally equivalent to the worker caste in other species, but anterior part of the pronotum. see mesozona, metazona. remains able to develop into other castes. prozonite n. [Gr. pro, before; zone, belt] (ARTHRO: Diplopoda) pseudibacus n. [Gr. pseudos, false; bacca or baca, pearl] (AR- The anterior portion of a diplosomite, when the tergum is THRO: Crustacea) Postlarval stage of decapod Scyllaridae; divided by a transverse groove. see metazonite. nisto; puerulus. 750 751 Maggenti and Gardner On line Di ctio nar pseudoacrorhagi n.pl.; sing. -us [Gr. pseudos, false; acron, how derived, usually coymofprising the nematodes, rotifers, Inve top; rhax, berry] (CNID: Anthozoa) In some Actiniaria, hol- nematomorphs, gastrotrics, andrtkebinorhynchs. rate low, foliose expansions without nematocysts. pseudocoelomic membranes (NEMATA) AZoodelicate sheath in- log pseudoalleles n.pl. [Gr. pseudos, false; allelon, one another] vesting and supporting the internal orgyans, i.e., the Genes at closely adjacent loci that react in the allelism test esophagus, internal surface of muscle cells, and between as they were alleles and between which crossing over is each pair of muscles to the hypodermis. rare. pseudocoelomocytes see coelomocytes pseudocardinal a. [Gr. pseudos, false; L. cardinalis, chief] pseudocompatability n. [Gr. pseudos, false; L. cum, with; (MOLL: Bivalvia) Pertaining to irregularly shaped teeth close pati, suffer] Fertilization occurring under unusual condi- to the beak. tions, that would not normally happen. pseudo-annuliform see pseudoannulation pseudocone a. [Gr. pseudos, false; konas, cone] (ARTHRO: In- pseudoannulation n. [Gr. pseudos, false; L. annulus, ring] secta) In certain Diptera and Odonata, a condition where Annulation involving cuticle only, does not involve the the cone of the ommatidium is liquid-filled or gelatinous coelom. rather than a crystalline cone (eucone condition). pseudoaposematic colors see pseudaposematic colors pseudocopulation n. [Gr. pseudos, false; L. copula, bond] pseudobaccus see pseudibacus (ARTHRO: Insecta) Pollinization of a flower by copulation of a male insect mistakenly recognizing it as a female insect. pseudobranch n. [Gr. pseudos, false; branchia, gills] (MOLL: Gastropoda) In some aquatic Pulmonata, a secondary gill pseudocrop n. [Gr. pseudos, false; A.S. crop, craw] (ARTHRO: consisting of folds of the mantle near the pneumostome. Insecta) In Hemiptera, an enlargement of the anterior region of the mid-gut dilated in a comparable manner as a pseudobulb n. [Gr. pseudos, false; L. bulbus, bulb] (NEMATA) stomodeal crop. Muscular swelling of the esophagus lacking a valvular arrangement. pseudocruralium n. [Gr. pseudos, false; crus, leg] (BRACHIO) Dorsal adductor impressions elevated above the valve pseudocardia see dorsal vessel floor. pseudocephalon see hemicephalous pseudoctenodont shell (MOLL: Bivalvia) A shell with many pseudocercus see urogomphus short teeth transverse to the hinge margin that are in pseudochrysalis see semipupa groups related to others with some teeth longitudinally directed. see ctenodont shell. pseudocircle of crochets (ARTHRO: Insecta) Crochets of larvae consisting of a well developed mesoseries and a row of pseudoculus n.; pl. -culi [Gr. pseudos, false; L. oculus, eye] small hooks (lateroseries) on the lateral aspect of the pro- (ARTHRO: Insecta) In Protura, a circular dome of thin, per- leg. forated cuticle on the head, having 2-6 neurons with ciliary dendritic processes; thought to be a chemoreceptor, an pseudocoel, pseudocele n. [Gr. pseudos, false; koilos, hol- antennal base, or organs of Tomosvary. low] A body cavity not lined with a mesodermal epithelium. see Aschelminthes, Pseudocoelomata. pseudodeltidium see deltidium pseudocoel cells see coelomocytes pseudoderm n. [Gr. pseudos, false; derma, skin] (PORIF: Cal- carea) In the most complex sponges of the Leucosolenia, Pseudocoelomata n.; pl. -ates [Gr. pseudos, false; koilos, the outermost asconoid bodies are fused together to form a hollow] A group of phyla having a pseudocoelom, no matter 752 753 Maggenti and Gardner On line Di ctio nar false surface. pseudointerarea n. [Gr. psyeoufdos, false; inter, between; area, Inve pseudoerucism n. [Gr. pseudos, false; L. eruca, caterpillar] space] (BRACHIO:Inarticulata) rFtelabttened posterior part of rate (ARTHRO: Insecta) Erucism caused by toxic setae in the the shell, secreted by posterior partZooof the mantle, not log adult female. see lepidopterism. fused with opposite valve. y pseudofaeces n.pl. [Gr. pseudos, false; L. faex, dregs] (MOLL: pseudolabia n. [Gr. pseudos, false; L. labium, lip] (NEMATA) In Bivalvia) Particulate matter from the gills and/or excess Spirurida, cuticular outgrowths arising around the oral food formed into masses by mucus for discharge from the opening. mantle cavity; particulate matter is not passed through the pseudolateral a. [Gr. pseudos, false; L. latus, side] (MOLL) gut. The false lateral teeth; lateral tooth close to the beak. pseudofertility see pseudocompatability pseudolips see pseudolabia pseudofertilization see pseudogamy pseudomanubrium n. [Gr. pseudos, false; L. manubrium, pseudogamy n. [Gr. pseudos, false; gamos, marriage] Apo- handle] (CNID: Hydrozoa) A long subumbrellar extension mictic parthenogenesis; development of a female gamete containing the radial canals. after stimulation (without fertilization) by a male gamete; pseudometamerism n. [Gr. pseudos, false; meta, after; also termed pseudofertilization, pseudomixis, and also gy- meros, part] 1. False segmentation. 2. (PLATY: Cestoda) nogenesis. Serial segmentation appearing like metamerism. pseudogaster n. [Gr. pseudos, false; gaster, belly] (PORIF) A pseudomixis see pseudogamy cavity into which true oscula open and from which pseudo- pseudomonocyclic a. [Gr. pseudos, false; monos, one; kyk- oscula open to the exterior. los, circle] (ECHINOD: Crinoidea) The presence in young and pseudogastrula see amphiblastula absence in adults of the infrabasal plates; cryptodicyclic. pseudogermes n. [Gr. pseudos, false; germen, bud] (ARTHRO: pseudomyiasis n. [Gr. pseudos, false; myia, fly] Presence Insecta) Multicellular fragments of braconid Hymenoptera within a host of the larva of a Diptera not normally para- embryonic membranes found in parasitized Pieris Lepidop- sitic. tera, that become vacuolated and nuclei break down. pseudonchs n.pl. [Gr. pseudos, false; onkos, hook] (NEMATA) pseudogiant fiber see giant fiber Structures in the pharynx that appear to resemble onchia. pseudogyne n. [Gr. pseudos, false; gyne, woman] (ARTHRO: pseudonest n. [Gr. pseudos, false; A.S. nest] (ARTHRO: In- Insecta) In Hymenoptera, a defective ant, characterized by secta) In Bombidae, an accumulation of nest building ma- having a female thorax with the stature, gaster and head of terials found near the entrance to the nest that at times the worker, thought to result from having parasitic beetles shelter workers. in their colony. Pseudoneuroptera n. [Gr. pseudos, false; neuron, nerve; pseudohalteres n.pl. [Gr. pseudos, false; halter, balancer] pteron, wing] (ARTHRO: Insecta) Formerly, net-winged in- (ARTHRO: Insecta) In Strepsiptera (stylopids), the anterior sects with incomplete metamorphosis (Ephemeridae, Odo- wings represented by small club-like processes that func- nata, Plecoptera, Isoptera and Corrodentia); Archiptera. tion like the halteres of Diptera. pseudonocytoid see oenocytoid pseudoheart n. [Gr. pseudos, false; A.S. heorte, heart] 1. pseudonotum see postscutellum (ANN) see commissural vessels. 2. (ECHINOD) The axial gland. pseudonuclei n.pl. [Gr. pseudos, false; L. nucleus, kernal] 754 755 Maggenti and Gardner On line Di ctio nar (ARTHRO: Insecta) During development, nodules of uric acid pseudopolyploidy n. [Gr. pysoefudos, false; poly, many; aploos, Inv that appear in the fat cells. onefold] Chromosome sets inertegroups of related species bra having numerical relationship leadintegZto erroneous inter- pseudonychia n.pl.; sing. -ium [Gr. pseudos, false; onyx, ool ogy claw] (ARTHRO: Insecta) In Collembola, a basal tooth-like pretation as polyploids. formation on the pretarsus. pseudopore n. [Gr. pseudos, false; poros, passage] 1. (BRYO: pseudonymph, semipupa see prepupa Stenolaemata) In Cyclostomata, a pore in the calcified wall of a zooid that is obstructed by organic matter. 2. (PORIF: pseudo-osculum n.; pl. -ula [Gr. pseudos, false; L. osculum, Calcarea) In Leucosolenia, a large opening through the small mouth] (PORIF) The exterior opening of the pseu- pseudoderm. dogaster; a pseudostoma. Pseudoptera n. [Gr. pseudos, false; pteron, wing] (ARTHRO: pseudopallium n. [Gr. pseudos, false; L. pallium, mantle] Insecta) Formerly an ordinal name for scale insects. (MOLL: Gastropoda) In some parasites of Echinoderms, a ring-like fold of the anterior part of the snail growing over pseudopuncta n.; pl. -ae [Gr. pseudos, false; L. punctum, the visceral mass and serving as a brood chamber. small hole or spot] (BRACHIO) A type of shell punctation that points inwardly, appearing on the internal surface as a pseudopenis n. [Gr. pseudos, false; L. penis, male copulatory bump. pseudopunctate a. see endopuncta. organ] (ANN: Oligochaeta) The eversible area of the body wall or atrium tip. pseudopupa n. [Gr. pseudos, false; L. pupa, puppet] (ARTHRO: Insecta) In Coleoptera and Meloidae, a larva in a quiescent pseudoperculum n. [Gr. pseudos, false; L. operculum, lid] pupa-like condition preceding one or more larval instars (ARTHRO: Insecta) On the eggs of Heteroptera, an inde- before the true pupal stage; a coarctate larva; a semipupa. pendently evolved cap-like structure. pseudopupillae n.pl.; sing. -a [Gr. pseudos, false; L. pupilla, pseudopillar n. [Gr. pseudos, false; L. pila, pillar] (MOLL: Bi- dim. pupa, puppet] (ARTHRO: Insecta) In Odonata, black valvia) Low, broad inward projection of the shell wall. spots on the compound eyes of live specimens. pseudoplacenta n.; pl. -tae [Gr. pseudos, false; L. placenta, pseudorhabdite n. [Gr. pseudos, false; rhabdos, rod] (PLATY: cake] (ARTHRO: Insecta) Embryonic or maternal structures Turbellaria) An amorphous mass of slimy material in the of certain female viviparous insects that are presumed to epidermal cells; possibly related to rhabdites. give nourishment to the developing larvae; however, the physiological evidence of the importance of this structure is pseudorostrum n. [Gr. pseudos, false; L. rostrum, bill] (AR- uncertain. THRO: Crustacea) In Malacostraca Cumacea, paired forward projecting plates on the anterior carapace. pseudoplacental viviparity (ARTHRO: Insecta) Referring to insects that produce eggs, containing little or no yolk, that pseudosclerite n. [Gr. pseudos, false; skleros, hard] (ARTHRO: are retained by the female in the ovariole up to the time of Chelicerata) In Acari, sclerotized area of the cuticle differ- hatching. see pseudoplacenta. ing distinctly from the soft cuticle. pseudopod, pseudopodium n.; pl. -dia [Gr. pseudos, false; pseudoscolex n. [Gr. pseudos, false; skolex, worm] (PLATY: pous, foot] 1. Temporary protrusion of the cell, associated Cestoda) Distortion of the anterior proglottids into a hold- with flowing movement of protoplasm, functioning in loco- fast where the true scolex is lost in early development; the motion and feeding. 2. (ARTHRO: Insecta) An outgrowth or deutoscolex. foot-like appendage of the larval body, assisting in locomo- pseudosegments n. [Gr. pseudos, false; L. segmentum, tion. see parapodium. piece] (PLATY: Cestoda) The discreet, flattened sections making up the major part of the body; each being a repro- 756 757 Maggenti and Gardner On line Di ctio nar ductive packet; a proglottid. predator or parasite gaiynionfg nourishment from the trophal- Inv lactic secretions of the host larevratee. pseudoselenizone n. [Gr. pseudos, false; selene, the moon; bra te Z zone, girdle] (MOLL: Gastropoda) A band of crescentic pseudotagma n. [Gr. pseudos, false; tagmooal, a division] (AR- ogy growth lines on the shell surface resembling a selenizone, THRO: Chelicerata) In Acari, a region of a body division, but not identifiable as caused by a notch or slit in the ap- such as gnathosoma, idiosoma, proterosoma and hystero- erture. soma. pseudosematic see sematic pseudotaxodont a. [Gr. pseudos, false; taxis, arrangement; pseudoserosa n. [Gr. pseudos, false; L. serum, whey] In em- odon, tooth] (MOLL: Bivalvia) With numerous irregular short bryology, membrane formed during splitting of the blasto- teeth transverse to the hinge, but are not related to cteno- derm in the morula stage. dont or pseudoctenodont forms. pseudosessile a. [Gr. pseudos, false; sessum, sitting] (AR- pseudotela n.; pl. -ae [Gr. pseudos, false; tela, end] THRO: Insecta) In Hymenoptera, appearing sessile due to (BRACHIO) One of a pair of external projections of the shell having the abdomen usually basally constricted and its first near the pedicle (not beak ridges). segment fused with the metathorax. pseudotetramerous a. [Gr. pseudos, false; tetra, four; pseudosiphon n. [Gr. pseudos, false; siphon, tube] (MOLL: Bi- meros, part] Appearing as having 4 joints, where there are valvia) In oysters, two opposing mantle edges that form a actually 5. hole which is not functional. pseudotrachea n. [Gr. pseudos, false; tracheia, windpipe] 1. pseudospherule n. [Gr. pseudos, false; dim. sphaira, ball] A trachea-like structure. 2. (ARTHRO: Crustacea) In terres- (CNID: Anthozoa) In Actinaria, a vesicle at the margin, of- trial Isopoda, a respiratory structure developed in the pleo- ten with an aperture containing basitrichous isorhiza. pods for air-breathing. 3. (ARTHRO: Insecta) In Diptera, small, specialized channels of the labellum that open to the pseudospondylium n. [Gr. pseudos, false; spondylos, joint] exterior of the oral lobes and pass liquid food to the food (BRACHIO) A cup-shaped chamber accommodating the canal. ventral muscle field, contained between dental plates. pseudotrimerous a. [Gr. pseudos, false; treis, three; meros, pseudosternite see epiphallus part] Appearing as 3 jointed, when actually having 4 joints pseudostigmatic organ (ARTHRO: Chelicerata) In Acari, one or segments. of two organs of sensory setae, various in shape, arising pseudotroch n. [Gr. pseudos, false; trochos, wheel] (ROTIF) from a cupule or pit located on the cephalothorax of An enlarged arc of stiff cirri in the supra-oral region of the Oribatida; thought to detect air movements and thus avoid buccal field. desiccation. pseudovarium n. [Gr. pseudos, false; L. ovarium, ovary] An pseudostoma n. [Gr. pseudos, false; stoma, mouth] A mouth- ovary producing pseudova. see pseudovum. like opening. pseudovelum n. [Gr. pseudos, false; L. velum, veil] (CNID: pseudosymmetry n. [Gr. pseudos, false; symmetria, due pro- Scyphozoa) A narrow shelf-like flange with no muscules portion] Approximate symmetry of a structure divided by a and nerves projecting inward from the margin of the bell. plane that divides the structure into halves that are less than symmetrical. pseudovesicles n. [Gr. pseudos, false; L. vesicula, little bladder) (ANN: Oligochaeta) Structures, serially homologous pseudosymphile n. [Gr. pseudos, false; syn-, together; with seminal vesicles, on the posterior faces of 12/13 or philein, to love] (ARTHRO: Insecta) In social insects, a 13/14. 758 759 Maggenti and Gardner On line Di ctio nar pseudovitellus see mycetome pterocardiac a. [Gr. pteroyno,f wing; kardia, heart] (ARTHRO: Inv Crustacea) In Decapoda, a gasetrrtiec mill ossicle in the form of pseudovum n.; pl. -ova [Gr. pseudos, false; L. ovum, egg] An bra a curved triangular plate articulatingtewZith the mesocardiac unfertilized egg that can undergo development. ool ossicle along the broad base, with the benotgaypex connected pseudozoea n. [Gr. pseudos, false; zoe, life] (ARTHRO: Crusta- to the anterior process of the zygocardiac ossicle; in a few cea) In Hoplocarida, a larval form of carnivorous mantid species these ossicles are slightly elongated and straight. shrimp with segmented abdomen bearing biramous appendages and 2 pairs of appendages on the thorax (the pterodinergate n. [Gr. pteron, wing; deinos, terrible; ergate, second pair specialized as raptorial limbs); used to include worker] (ARTHRO: Insecta) In Hymenoptera, a member of the erichthus and alima stages of Stomatopoda larvae or the soldier caste with vestigial wings. their early stages. see antizoea. pteropleural bristles (ARTHRO: Insecta) In Diptera, bristles on pseudumbilicus n. [Gr. pseudos, false; L. umbilicus, navel] the pteropleuron. (MOLL: Gastropoda) A depression or cavity in the shell base pteropleurites see mesepimeron only in the last whorl; a false umbilicus. pteropleuron n.; pl. pteropleura [Gr. pteron, wing; pleuron, ptenoglossate a. [Gr. ptenos, feathered; glossa, tongue] side] (ARTHRO: Insecta) In Diptera, a sclerite on the side of (MOLL: Gastropoda) Referring to a broad radula, lacking a the thorax, below the base of the wing; the upper part of central tooth, having numerous, arcuate, sharp, similarly the mesepimeron. shaped teeth in oblique rows, and increasing in size later- pteropods n.pl. [Gr. pteron, wing; pous, foot] (MOLL: Gastro- ally. poda) Two orders of small swimming, pelagic Opisthobran- pteralia n.pl. [Gr. pteron, wing] (ARTHRO: Insecta) The wing- chia, the shelled Thecosomata, and the naked Gymnoso- flexing sclerites of the wing base; axillaries. mata lacking a shell. pterate see alate pterostigma n.; pl. -mata [Gr. pteron, wing; stigma, mark] pterergate n. [Gr. pteron, wing; ergates, worker] (ARTHRO: (ARTHRO: Insecta) A thickened opaque spot along the costal Insecta) In Hymenoptera, a worker or soldier ant with ves- margin of the wing tip of several orders; stigma; bathmis. tigial wings. pterote see alate pteridine n. [Gr. pteron, wing; eidos, like] Tetrazanaphthaline pterothecae n.pl. [Gr. pteron, wing; theke, case] (ARTHRO: derivatives, widespread in nature; important in natural Insecta) In larvae of Diptera, adhering sheaths of the pigmentation. wings. pterine (pteridine) pigments A group of nitrogen-containing pterothorax n. [Gr. pteron, wing; thorax, chest] (ARTHRO: In- compounds producing leucopterin (white), xanthopterin secta) Collectively, the meso- and metathoracic segments (yellow) the most widely distributed, isoxanthopterin (pur- of certain wing-bearing insects; synthorax. pterothoracic ple florescence) and biopterin (blue floresence); pigments a. important in the natural pigmentation of many inverte- pterygium n.; pl. -gia [Gr. dim. pteryx, little wing] (ARTHRO: brates, as well as plants. Insecta) 1. The small lobes at the base of the underwings. pternotorma n.; pl. -mae [Gr. pterna, heel; torma, socket] 2. In Coleoptera, the lateral process of the snout. (ARTHRO: Insecta) In scarabaeoid larvae, a stoutly curved pterygobranchiate a. [Gr. pteryx, wing; branchia, gills] (AR- process at the end of the laeotorma and occasionally of the THRO: Crustacea) Having spreading, feathery gills. dexotorma. pterygoda see patagia 760 761 Maggenti and Gardner On line Di ctio nar pterygogenea n.pl. [Gr. pteryx, wing; genos, race] (ARTHRO: addition to a median indyenoftation. ptycholophus n. Inv Insecta) 1. Winged adult insects. 2. Descended from erte pubescence n. [L. pubescere, to growbrahairy] A covering of fine winged ancestors. see apterygogenea. te Z soft hairs. pubescent a. ool ogy pterygoid a. [Gr. pteryx, wing; eidos, like] Wing-like. pubic a. [L. pubes, adult] Referring to the area of the genitalia. pterygopolymorphism n. [Gr. pteryx, wing; polys, many; pubic process (ARTHRO: Insecta) In Scarabaeoidea, fused pu- morphos, shape] (ARTHRO: Insecta) Occurrence of different bic plates above the second valvifers (fused second valvu- forms of wings in the same species. lae). pterygostomial region (ARTHRO: Crustacea) In Decapoda, the puce n. [L. pulex, flea] Dark brown or purplish brown. anterolateral part on the ventral surface of the carapace, on opposite sides of the buccal cavity; jugal region; ptery- pudendum n. [L. pudenda, external genitals] External female gostome. genitalia; the vulva. pterygostomial spine (ARTHRO: Crustacea) In Decapoda, a puerulus n. [L. puerilis, childish] (ARTHRO: Crustacea) 1. spine on the anterolateral angle. Preadult stage of Decapoda Scyllaridae; nisto, pseudibacus. 2. Preadult stage of Decapoda Palinuroidea. Pterygota, pterygotes n.; n.pl. [Gr. pterygotos, winged] (AR- THRO: Insecta) A subclass containing the winged and sec- puffs n. [ME. puf] (ARTHRO: Insecta) In Diptera, a process in ondarily apterous insects, with varied metamorphosis, and which the bands (chromomeres) of the chromosomes of have no pregenital abdominal appendages. see Exoptery- the salivary glands undergo puffing which is usually corre- gota, Endopterygota. lated with the production of exportable proteins in the glandular cells; thought to reflect gene activity. ptilinal suture (ARTHRO: Insecta) In Diptera, a crescent- shaped groove, situated on the lower part of the frons be- pulmonarium n.; pl. -ria (ARTHRO: Insecta) A type of abdo- tween the bases of the antennae and the eyes, which usu- men with membranous connections between the sclerites ally extends ventrally into the facial area; frontal suture. of the terga and pleura of the abdominal rings. ptilinum n.; pl. ptilina [Gr. ptilon, feather] 1. (ARTHRO: In- pulmonary a. [L. pulmo, lung] Pertaining to the lungs. secta) In Diptera, a temporary bladderlike structure of a pulmonary cavity/sac (MOLL: Gastropoda) In Pulmonata, a pupa that can be inflated and thrust out through the frontal pallial cavity formed by transverse vascularizations of the (ptilinal) suture, just above the bases of the antennae, that interior dorsal wall. pushes off the operculum of the puparium. 2. (NEMATA) pulsatile vesicles (ANN: Hirudinoidea) Eleven small hemi- Sometimes inappropriately used to describe horn-like or spherical pulsing structures filled with coelomic fluid. leaf-like ornamentation on the anterior extremity of parasitic forms. pulsating vesicle (ROTIF) Small bladder-like excretory organ into which the flame bulb system empties. ptilota n. [Gr. ptilon, feather] (ARTHRO: Insecta) Winged insects. pulverulent a. [L. pulvereus, full of dust] Powdery; dusty; farinaceous. ptychoidy n. [Gr. ptyche, fold] (ARTHRO: Chelicerata) In Oribatida, an articulation between the prosoma and opist- pulvilliform a. [L. pulvillus, little cushion] (ARTHRO: Insecta) hosoma, allowing the legs to be concealed by down folding Appearing lobelike or padlike; shaped like a pulvillus. of the prosoma. pulvillus n.; pl. -li [L. pulvillus, little cushion] (ARTHRO: In- ptycholophous a. [Gr. ptyche, fold; lophos, crest] (BRACHIO) secta) In Diptera, the pad of the membranous lobe beneath A lophophore with brachia folded into one or more lobes in the tarsal claw, arising from the base of each auxilia. see 762 763 Maggenti and Gardner On line Di ctio nar empodium. pupa dectica (ARTHRO: Insyecotfa) A pupa with articulated man- Inv dibles that can be used by tehrete pharate adult. see pupa pulvinate a. [L. pulvinus, cushion] 1. Moderately convex or bra adectica. te Z swelled. 2. Cushion-like. ool ogy pulvinulus see arolium pupa dermata (ARTHRO: Insecta) A pupa retaining the larval skin without indication of future limb placement. pumping pharyngeal tube see food meatus pupa exarate (ARTHRO: Insecta) An adecticous pupa in which punctae n.pl.; sing. puncta [L. punctum, small hole or spot] the appendages are free and not cemented to the body Small pores, holes, or dots on a surface. wall; pupa exarata. see pupa obtect. punctate a. [L. punctum, small hole or spot] Covered with pupa folliculata (ARTHRO: Insecta) A pupa enclosed in a theca small pores, holes, or dots. or cocoon. punctulate a. [L. punctum, small hole or spot] Dotted with pupa incompletae (ARTHRO: Insecta) A Lepidoptera pupa with minute impressions. more than three movable abdominal segments. punctum n. [L. punctum, small hole or spot] A small pit or pupal-adult apolysis (ARTHRO: Insecta) In Diptera, the in- spot on a surface. terim between phanerocephalic pupa and pharate adult. puncture n. [L. punctura, hole] A small hole; a minute punc- pupa larvata (ARTHRO: Insecta) A pupa in which the forming ture-like depression. adult appendages are apparent on the surface of the theca pupa n.; pl. pupae [L. pupa, puppet] (ARTHRO: Insecta) The or cocoon; a masked pupa. usually quiescent stage between the larva and adult in pupa libera (ARTHRO: Insecta) A Lepidoptera pupa with many complete metamorphosis. free segments. pupa adectica (ARTHRO: Insecta) A pupa without articulated pupal respiratory horn see respiratory horn mandibles for use by a pharate adult. see pupa dectica, pupa exarate, pupa obtect. pupa nuda (ARTHRO: Insecta) An insect pupa free from attachment. pupa adheraena (ARTHRO: Insecta) A pupa which hangs head down in a perpendicular manner. pupa obtect (ARTHRO: Insecta) An adecticous pupa in which the appendages are more or less strongly cemented to the pupa angularis (ARTHRO: Insecta) A pupa bearing a pyramidal body, assumed by tanning of protein in the molting fluid; process or nose on its dorsal surface. pupa obtecta. pupa-chromogenic phase (ARTHRO: Insecta) The last pupal pupariation n. [L. pupa, puppet] (ARTHRO: Insecta) In certain phase before the adult, in which pigmentation occurs. families of Diptera, formation of a puparium by a third pupa-chromoptic phase (ARTHRO: Insecta) The pupal phase stage, nonfeeding larva; a post-feeding larva. (after telemorphic) when pigmentation of the compound puparium n. [L. pupa, puppet] (ARTHRO: Insecta) 1. In certain eyes begin. families of Diptera, a case formed by the hardening of the pupa coarctate (ARTHRO: Insecta) Puparium or last larval skin next to the last larval skin, in which the pupa is formed; enclosing the exarate pupa; found in many Diptera. pupa coarctate. 2. Sometimes used in a few parasitic Hy- pupa conica (ARTHRO: Insecta) A conical, nongular pupa. menoptera and Coleoptera for the cast exuviae held at the posterior end of the larval body. 3. In Diaspidine scales, pupa custodiata (ARTHRO: Insecta) A pupa in a partially open used for the scale of mixed exuviae and wax or for the fe- cocoon. male enclosed in the unruptured cuticle of the last larval 764 765 Maggenti and Gardner On line Di ctio nar stage. see pupillarium. smaller than a tubercle.y 2of. (BRYO) A small regular skeletal Inv structure of crinkled laminae. erte pupa subterranean (ARTHRO: Insecta) A pupa submerged into bra te Z the soil during transformation; pupa subterranea. putative a. [L. putare, to think] Commonlyoorlegarded as such; ogy pupate v. [L. pupa, puppet] The transformation to a pupa. reputed to be; supposed. pupiferous a. [L. pupa, puppet; fero, bear] (ARTHRO: Insecta) pycnosis n. [Gr. pyknos, dense] Degeneration of a cell nucleus In Hemiptera, the generation of aphids that produce sexed characterized by condensation and an increased affinity for individuals. stain. pycnotic a. pupiform a. [L. pupa, puppet; forma, shape] Cylindrical, with pygal a. [Gr. pyge, rump] Situated back, or pertaining to the rounded ends; cocoon-shaped; a pupiform shell. posterior end of the back. pygidial a. pupigerous see pupa coarctate pygidial fringe (ARTHRO: Insecta) In homopteran Coccoidea, the projecting ends of the lateral margin of the pygidium; pupil n. [L. pupilla, pupil of eye] (ARTHRO: Insecta) The central the lateris. spot of an ocellus. pygidial glands (ARTHRO: Insecta) 1. In Coleoptera, paired pupillarium n. [L. dim. pupa, puppet] (ARTHRO: Insecta) In organs opening beneath the last abdominal tergite that Diaspididae, the adult female shrinks inside the exuviae of function to secrete a corrosive, pungent defense fluid, or a the second larval stage and lives and lays eggs inside. pu- substance that lowers surface tension of the water to in- pillarial a. crease propulsion; also called anal glands. 2. In Hymenop- pupillate a. [L. pupilla, pupil of eye] Having an eye-like center; tera, associated with the membrane between abdominal a spot or mark. terga 6 and 7 of Formicidae, and when enlarged, produce a pupipara n. [L. pupa, puppet; parere, to beget] (ARTHRO: In- defensive secretion; also called anal glands. see post-py- secta) In Diptera, a convenience group in which wings are gidial gland. reduced, direct reproduction of puparia, with development pygidial incision see anal cleft taking place within the mother. see nymphipara. pygidial plate (ARTHRO: Insecta) In Hymenoptera, a flat plate pupiparous a. [L. pupa, puppet; parere, to beget] (ARTHRO: surrounded by a carina or line, sometimes an apical pro- Insecta) Bearing larva that are full grown and ready to pu- jection on the 6th gastral tergite in females and 7th in pate. males. pupoid a. [L. pupa, puppet; Gr. eidos, form] 1. Pupiform. 2. pygidial setae see anal setae (ARTHRO: Diplopoda) The final embryo at hatching, without pygidium n.; pl. -dia [Gr. pygidion, narrow rump] 1. (ANN) legs or segmentation visible. The telotroch and anal region behind it, bearing cirri. 2. pure line population Descendants through self-fertilization of (ARTHRO: Insecta) The last dorsal segment of the body. a single homozygous parent or highly inbred line of animals pygal, pygidial a. obtained by long continued inbreeding. pygofer n. [Gr. pyge, rump; L. fero, carry] (ARTHRO: Insecta) purine bases Nitrogen-containing organic cyclic bases that In Homoptera, the last abdomenal segment bearing lateral pair with pyrimidine bases in DNA and RNA replication. margins. purpuraceous a. [L. purpura, purple] Being purple in color. pygomere n. [Gr. pyge, rump; meros, part] (ANN: Oli- pustula, pustule n.; pl. -lae [L. pustula, blister] 1. An eleva- gochaeta) The terminal part of the body; sometimes called tion resembling a pimple, blister or wartlike projection; anal segment, although some of the characters of a 766 767 Maggenti and Gardner On line Di ctio nar metamere are missing. pyramid of energy Energyy orfelationships between the trophic Inve pygophore n. [Gr. pyge, rump; phoreus, bearer] (ARTHRO: In- levels in a food chain. rteb rate secta) 1. The pygofer. 2. In male Heteroptera, the 9th ab- pyramid of numbers Numbers of individZuoaols at the different log dominal segment. 3. In male Homoptera, the posterolateral trophic levels in a food chain. y extension of the 9th abdominal segment. pyriform a. [L. pyrum, a pear; forma, shape] Having the pygopid loop (BRACHIO) A short ringlike loop with slightly shape of a pear; round and large at one end, generally ta- arched cross band. pering to the other. pygopods n. [Gr. pyge, rump; pous, foot] (ARTHRO: Insecta) pyriform vesicle see Muller's organ The paired appendages of the 10th abdominal segment. pygostyle n. [Gr. pyge, rump; stylos, pillar] (ARTHRO: Insecta) In Hymenoptera, small lateral setigerous processes on the 9th gastral tergite. pyllopod n. [Gr. pyle, gate; pous, foot] (ARTHRO: Crustacea) In gnathiidean Isopoda, the second thoracopod; fused to the head resulting in the appendages being second maxilli- pedes and in males are flat and cover the buccal area, but in females, a short palp with a large flat plate attached. pyloric valve 1. (ARTHRO: Insecta) A regulatory (sphincter) at the entrance to the intestine from the stomach; usually located behind the stomach in the anterior part of the proctodeum. 2. (ARTHRO: Crustacea) see cardiac pyloric valve. pylorus n. [Gr. pyloros, gatekeeper] 1. (ARTHRO: Insecta) A short distinct section of the proctodeum intervening between the ventriculus and true intestinal tube, containing the pyloric valve. 2. (BRYO) Ciliated part of the digestive tract into which the stomach part of the cardia empties. pyloric a. pyraform glands (ACANTHO) Glands in the tail of some males; function unknown. pyraform organ see esophageal bulb pyramid n. [Gr. pyramis, pyramid] 1. Any conical or triangular structure. 2. (ECHINOD: Echinoidea) The five large calcareous scraping plates that compose the Aristotle's lantern. pyramidal a. pyramid of biomass Weight relationships between the trophic levels in a food chain.