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

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

September 2005

Online Dictionary of Invertebrate Zoology: N

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: N" (2005). Armand R. Maggenti Online Dictionary of Invertebrate Zoology. 12. https://digitalcommons.unl.edu/onlinedictinvertzoology/12

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. 596 On line Di ctio nar Nassanoff's gland see Nasysoafnov's gland Inve N Nassanov's gland (ARTHRO: Insecrttae)b In Apis, a gland opening rate to the exterior beneath abdominal terZgoiotes six and seven, log that in pheromone production; welyl developed in workers, but absent in drones and maybe queens. n. [F. nacre, mother-of-] (MOLL) The pearly or iri- nasus n. [L. nasus, nose] (ARTHRO: Insecta) 1. The clypeal re- descent substance that lines the interior of shells, espe- gion; the drawn-out foreward part of the face. 2. In Isop- cially gastropods and pelecypods; mother-of-pearl; nacre- tera, the snout-like frontal projection that functions to eject ous a. poisonous or sticky fluids at intruders. naiad n. [Gr. Naias, water nymph] (ARTHRO: Insecta) In nasute n. [L. nasus, nose] (ARTHRO: Insecta) A type of soldier Hemimetabola, the aquatic, gill-breathing nymph. termite that bears a frontal snout-like projection or horn nail n. [A.S. naegel, nail] (ARTHRO) A tarsal claw; unguis. through which it ejects a defensive ; some possess large hooked mandibles, while in others the mandibles are naked a. [A.S. nacod, nude] Lacking the usual covering. greatly reduced. nanism n. [Gr. nanos, dwarf] Dwarfishness. nanoid a. natal a. [L. natalis, of birth] Of or pertaining to birth. nanitic worker (ARTHRO: Insecta) In Formicidae, dwarf work- natality rate Birth rate; the number of births per ers produced in first broods or later starved broods. unit during a given period of . nanometer n. [Gr. nanos, dwarf; metron, a measure] Unit of natant a. [L. natare, to swim] Adapted for swimming; floating; measurement equal to one billionth of a meter; also called swimming at the surface of the water. millimicron, micromillimeter and bicron. natatory a. [L. natare, to swim] Characterized by swimming; nanoplankton n. [Gr. nanos, dwarf; plankton, wandering] Mi- adapted for swimming. croscopic floating and . natatory lamellae (ARTHRO: Insecta) In Orthoptera Gryllotal- nanozooid n. [Gr. nanos, dwarf; zoon, animal; eidos, like] pidae, long slender plates of the hind tibiae. (BRYO: Stenolaemata) In Tubuliporidae, a polymorph with a single tentacle and reduced alimentary sac. nates n.pl. [L. natis, rump] The umbones of bivalves. narcosis n. [Gr. narke, numbness, torpor] Stupor or uncon- naticid a. [LL. naticae, buttocks] (MOLL: ) Pertain- sciousness caused by a drug or carbon dioxide build up in ing to Natica , a of carnivorous sea snail. the blood. naticiform a. [LL. naticae, buttocks; forma, shape] (MOLL: nasale n. [L. nasus, nose] (ARTHRO: Insecta) Anterio-median Gastropoda) Having globose last and small , like projection from the frons formed by fusion of frons, clypeus the shell of Natica. and labrum, or by frons and clypeus alone, especially some native a. [L. nativus, inherent, conferred by birth] and Coleoptera larvae. originating and living in a particular area; not im- nascent a. [L. nascens, arising, beginning] Beginning to exist, ported. grow, or develop; the act of being born. natural classification In , a classification of groups of naso n. [L. nasus, nose] (ARTHRO: ) In Acari, an organisms or objects to show their characteristics and acronal protuberance at the anterior of the body over- evolutionary relationships with each other. see artificial hanging the chelicerae. classification. 597 598 Maggenti and Gardner On line Di ctio nar natural decrease The rate of population decrease measured 2. (ARTHRO: Insecta) Tyhoef pupal stage. 3. (BRACHIO) A Inve by subtracting the natality rate from the mortality rate. see youthful stage when generic crhteabracters are beginning to rate natural increase. become apparent. 4. (BRYO) Zooids laiZdoodown in the phase log natural group A group of organisms having a common ances- of astogenic change. y tor. neap a. [ME. neep, neap] A series of tides exhibiting a small natural increase The rate of population increase measured by tidal range; occurring midway between spring tides. subtracting mortality rate from natality rate. Nearctic a. [Gr. neos, new; arkticos, bear] Pertaining to or natural requeening see supersedure belonging to a terrestrial division comprised of Greenland and North America, and including northern Mexico. The process of elimination of the least fitted individuals, and hence , by the natural conditions of neascus larva (PLATY: Trematoda) In Strigeidae and Dip- their . lostomatidae, a type of metacercaria with a cup-shaped forebody and a well developed hindbody. naupliar eye see nauplius eye nebulous a. [L. nebula, cloud] Clouded; marked with many naupliiform a. [L. nauplis, shellfish; forma, shape] (ARTHRO: scattered dilated colors or spots; indistinct. Crustacea) Pertaining to the nauplius larva. neck n. [A.S. hnecca, neck] 1. (ARTHRO: Insecta) The slender nauplius eye (ARTHRO: Crustacea) In nauplii and many adults, connecting structure between head and where the an unpaired median eye consisting of 1 to few light-sensi- head is free. 2. (MOLL) Distal part of the base of a si- tive cells; median eye; naupliar eye. phonostomatous shell, starting where outline of left side nauplius larva (ARTHRO: Crustacea) The earliest larval changes from convex to concave. 4. (PLATY: Cestoda) The stage(s), usually with one central eye, and characterized by unsegmented area between the scolex and strobilae. 3. having only three pairs of appendages: antennules, anten- (NEMATA) The slender, anterior portion of the body con- nae, and mandibles, all primarily of locomotive function. taining the esophagus. nautilicone a. [Gr. nautilos, shell; L. conus, cone] neck see (MOLL: Cephalopoda) Spirally coiled in a single plane. necrobiosis n. [Gr. nekros, corpse; bios, life] A series of nautiliform see changes occurring after the death of an individual . nautiloid a. [Gr. nautilos, nautilus shell; eidos, form] (MOLL: necrocytosis n. [Gr. nekros, corpse; kytos, container] Death Cephalopoda) Any nautilid shell coiled in a symmetrical in- of a cell. volute spiral; nautiliform. necrophagous a. [Gr. nekros, corpse; phagein, to eat] Feed- navicular a. [L. dim. navis, ship] Boatshaped; cymbiform; ing upon decaying flesh. scaphoid. necrophoresis, necrophoric behavior (ARTHRO: Insecta) neala n. [L. ne, not; ala, wing] (ARTHRO: Insecta) 1. The Carrying dead colony members away from the nest. jugum or jugal region of a wing. 2. Vannus necrosis n. [Gr. nekros, corpse; izein, cause to be] The death neallotype n. [Gr. neos, new; allos, other; typos, type] An al- of cells or tissues. lotype of the opposite sex from that described in the publi- necrotize v.t. [Gr. nekros, corpse] To kill cells and tissues in a cation of a neotype. living . neanic a. [Gr. neanikos, fresh] 1. Being youthful or immature; nectar n. [Gr. nektar, drink of the gods] A sweet substance a stage of development between the brephic and mature. secreted by flowers and certain leaves; the of many 599 600 Maggenti and Gardner On line Di ctio nar . Nemata, n.; ny.opfl. [Gr. nema, thread] A phylum Inve nectobenthic a. [Gr. nektes, swimmer; benthos, depths of the containing a large, diverse grorutepb of free-living, plant and rate sea] Organisms swimming freely on or near the bottom of animal parasitic roundworms, coveredZoboy cuticle and hav- log the sea. ing well developed nervous, reproductive yand digestive systems, but lack true segmentation, a true and nectocalyx see nectophore jointed appendages; formerly called Nematoda and Nema- nectochaeta larva (ANN: Polychaeta) A free swimming plank- toidea. togenic larva of some aquatic forms that bear rings of cilia Nemathelminthes n. [Gr. nema, thread; helmins, worm] A and 3 pairs of parapodia. former name for the phylum that included the phyla necton see nekton Nemata, Nematomorpha and Acanthocephala collectively. nectophore n. [Gr. nektos, swimming; phorein, to carry] nematicide see nematocide (CNID: Hydrozoa) In Siphonophora, the muscular swimming nematize v.i. [Gr. nema, thread] (NEMATA) To populate or in- bell that propels the colony; nectocalyx; nectozooid. see fest with nematodes. nematization n. pneumatophore. nematoblast n. [Gr. nema, thread; blastos, bud] (CNID) A cell nectopod n. [Gr. nektos, swimming; pous, foot] An appendage that forms a nematocyst; cnidoblast. adapted for swimming. nematocide n. [Gr. nema, thread; L. caedare, to kill] Any nectosome n. [Gr. nektos, swimming; soma, body] (CNID: Hy- agent lethal to nematodes. drozoa) In Siphonophora, the part that bears the swimming bells. nematocyst, cnida n. [Gr. nema, thread; kystis, bladder] (CNID) Intracellular that function in defense and nectozooid see nectophore capture of prey by injecting a toxin; in hydras, they func- Needham's sac/organ (MOLL: Cephalopoda) In males, a spe- tion in adhesion to the bottom; also called stinging cells, cialization of the sperm duct for formation and storage of nettle cells, or thread capsule or cell. see spirocyst. spermatophores; spermatophoric sac. nematocyte see plasmatocytes, cnidocyst negative geotropism Movement directed away from the Nematoda see Nemata earth's gravitational force. n. [Gr. nema, thread; eidos, form] A member of the negative phototropism The tendency to retreat from light. phylum Nemata negative tropism The tendency to retreat from stimuli. nematode wool see nema wool nekton n. [Gr. nektes, swimmer] Organisms that swim in the nematogen n. [Gr. nema, thread; genos, offspring] (MESO: open water, i.e., jellyfish, , , , seals and Rhombozoa) The vermiform adult that reproduces vermi- ; necton. see seston. form embryos. see rhombogen. nema n. [Gr. nema, thread] (NEMATA) Any individual of the nematoid a. [Gr. nema, thread; eidos, form] Thread-like. phylum Nemata; a nematode. Nematoidea see Nemata nema curds see nema wool nematology n. [Gr. nema, thread; logos, discourse] That nemaposit v.i. [Gr. nema, thread; L. ponere, to place] (AR- branch of zoology dealing with nematodes. THRO: Insecta) Mock oviposition by insects parasitized by nematodes; the deposits nematodes instead of their Nematomorpha, nematomorphs n.; n.pl. [Gr. nema, thread; own eggs. morphos, form] A phylum of worm-like animals that are 601 602 Maggenti and Gardner On line Di ctio nar free-living as adults and parasitic in as juve- Nemertini see y of Inv niles; horsehair worms; gordian worms. erte nemic a. [Gr. nema, thread] Of or perbtraaining to nematodes. te Z nematophagous a. [Gr. nema, thread; phagein, to eat] Feed- ool nemin n. [Gr. nema, thread] (NEMATA) An unkongoywn or uniden- ing on nematodes. tified endogenous substance in nematodes that causes trap nematophore n. [Gr. nema, thread; phorein, to carry] (CNID: formation by predacious fungi. Hydrozoa) A club-like or capitate ended structure in a hy- nemoricolous, nemoricole a. [L. nemus, woodland; colere, to droid colony containing nematocysts or adhesive cells; sar- dwell] Living in open woodland areas. costyle. neobiogenesis n. [Gr. neos, new; bios, life; genesis, begin- nematopore n. [Gr. nema, thread; poros, pore] (BRYO: ning] The theory that life may have been evolved several Stenolaemata) A slender tubular kenozooecium that opens ; recurring biopoiesis. see biogenesis. on the backside of the zoarium with tubules directed dis- tally. neoblast n. [Gr. neos, new; blastos, bud] Undifferentiated cells that migrate to wounds and participate in repair and re- nematosis n. [Gr. nema, thread; osis, denotes morbid condi- generation. tion] (NEMATA) A morbid state due to parasitism by nema- todes. Neo-Darwinism 1. The theory of stressing the conti- nuity of germ plasm and non-transmission of acquired nematosphere n. [Gr. nema, thread; sphaira, ball] (CNID: characters (Weismannism). 2. Any evolutionary theory Anthozoa) In Actinaria, a club-like tentacle tip. featuring natural selection. nematostat n. [Gr. nema, thread; stasis, stand] (NEMATA) 1. neogallicolae-gallicolae (ARTHRO: Insecta) In Phylloxeridae, Any phenomenon that holds a population in equilibrium. 2. dimorph fundatrigeniae that will become gallicolae (leaf gall A chemical that does not kill nematodes, but paralyzes formers). them. neogallicolae-radicolae (ARTHRO: Insecta) In Phylloxeridae, nematotheca n. [Gr. nema, thread; theke, case] (CNID: Hy- dimorph fundatrigeniae that will become radicolae (root drozoa) In Leptomedusae, small stemmed structures from gall formers). which nematophores develop; one-chambered, single and immovable; two-chambered, shaped like a wineglass, with neogea see neotropical region upper chamber capable of limited movement on its stem. neogeic a. [Gr. neos, new; ge, earth] Belonging to the West- nematozooid n. [Gr. nema, thread; zoon, animal; eidos, form] ern Hemisphere or New World. see gerontogeous. (CNID: Hydrozoa) A defense polyp; machozooid; dactylozo- neonatal a. [Gr. neos, new; L. natus, bborn] Recently born or oid. hatched. nema wool (NEMATA) Masses of cryptobiotic nematodes ad- neontology n. [Gr. neos, new; on, being; logos, discourse] hering to certain plant tissues (bulbs). The study of recent organisms. Nemertea, nemerteans, nemertines or rhynchocoels n.; neophorans n.pl. [Gr. neos, new; pherein, to carry] (PLATY: n.pl. [Gr. Nemertes, a nereid, sea nymph] A phylum of un- Turbellaria) 1. Individuals in which the yolk and oocytes are segmented, bilaterally symmetrical acoelomate worms, produced by a separate gland, or are produced in separate commonly called ribbon worms, that are predatory carni- parts of an ovovitellarium; ectolecithal eggs. see archoo- vores or scavengers that frequently use their eversible pro- phorans. 2. A former division of Turbellaria; a superorder. boscis to catch prey. neoplasm n.; pl. neoplasia [Gr. neos, new; plasma, formed 603 604 Maggenti and Gardner On line Di ctio nar or molded] An abnormal mass of tissue. gonad completes its deyvoeflopment prematurely before the Inve neosistens n. [Gr. neos, new; L. sistere, to stop] (ARTHRO: In- normal differentiation of imaginratel bstructures are completed. rate secta) In Adelgidae, the overwintering nymph of see hysterotely. 2. (ARTHRO) FurtheZrooclassified into two log the sistens. categories: prothetely and metathetely. neotyenic a. neosome n. [Gr. neos, new; soma, body] The entire organism neotrichy n. [Gr. neos, new; trichos, hair] (ARTHRO: Chelicer- altered by neosomy. ata) In Acari, secondary formation of setae by multiplica- tion of primary setae in a given area. neosomule n. [Gr. neos, new; dim. soma, body] The new structure that results from the neosomic process. neotropical region A zoogeographical region extending south from the Mexican Plateau throughout Central America, the neosomy n. [Gr. neos, new; soma, body] External transfor- Caribbean and South America. mation, during the formation of new cuticle, in an active stadium of a group normally metamorphosing by molts, neotype n. [Gr. neos, new; typos, type] A single specimen se- i.e., certain insects, acarines, crustaceans and nematodes. lected as the type specimen from as near to the original lo- neosomic a. cale as practicle in cases where the original types are known to be destroyed or are lost. neostigma n. [Gr. neos, new; stigma, point] (ARTHRO: Cheli- ) In Prostigmata Acariformes, a secondary spiracle neozoology see neontology near the base or farther forward of the chelicera. nephridial papilla (ANN) The projection marking the opening neotaxy n. [Gr. neos, new; taxis, arrangement] A secondary of the excretory organ. change of characters during phylogeny. nephridioblast n. [Gr. nephros, ; blastos, bud] An ecto- neoteinia see neoteny dermal cell that is precursor to a . neote(i)nic a. or n. [Gr. neos, new; teinein, to extend] (AR- nephridiopore n. [Gr. nephros, kidney; poros, pore] 1. The THRO: Insecta) In Isoptera, a supplementary reproductive exterior opening of an excretory organ (nephridium). 2. in a colony that may retain some juvenile characters; the (ARTHRO: Crustacea) see nephropore. word is used both as a noun and adjective (a neoteinic or nephridiostome see nephrostome neoteinic reproductive). Now spelled neotenic nephridium n.; pl. -ia [Gr. dim. nephros, kidney; L. ium, na- neotenic see neoteny ture of] 1. In various , simple or branched, neotenic plerocercoid (PLATY: Cestoda) All adult Caryophyl- tubular structures that function in , opening to the lidea, whose adult developmental forms are thought to be outside through a nephridiopore. see protonephridium, extinct; exception: Archigetes. see neotenic procercoid. metanephridium. 2. (ANN: Oligochaeta) A segment essen- tially composed of excretory tubules that may discharge neotenic procercoid (PLATY: Cestoda) In Caryophyllidea, adult directly onto the body surface, or lead to a sinus discharg- Archigetes that reaches sexual maturity complete with cer- ing to the exterior through pores by the setal ring. 3. comer. (ECHI) One to many organs used for the temporary storage neotenic see neoteny of eggs and sperm. neotenin n. [Gr. neos, young; teinein, to extend] One of the nephroblast see nephridioblast juvenile harmones. nephrocytes n.pl. [Gr. nephros, kidney; kytos, container] Cells neoteny, enoteinia, neoteiny n. [Gr. neos, young; teinein, to that occur singly or in groups in various parts in an inver- extend] 1. A term referring to the condition in which the tebrate body and function to transform original waste ma- 605 606 Maggenti and Gardner On line Di ctio nar terial into a form with which the metabolic pathways can nerve n. [L. nervus, nerve]y1o.f A single fiber or group of fibers Inve deal. of the peripheral nervous systertmeb. 2. (ARTHRO: Insecta) A rate nephrodinic a. [Gr. nephros, kidney; odis, labor] Having a tubular wing vein. Zoo log single duct serving both excretory and genital purposes. nerve cell see neuron y nephrogonoduct n. [Gr. nephros, kidney; gonos, progeny; L. nerve ending The terminal arborization of a neuron. ductus, leading] Combined genital and excretory ducts. nerve fiber The dendrite or collateral branch of a neurocyte. nephromixium n.; pl. -ia [Gr. nephros, kidney; mixis, min- nerve net A network of nerve cells connecting sensory and gling] An organ with flame cells and coelomic funnel serv- muscular elements in certain cnidarians, ctenophores, ing as both excretory and genital duct; a nephrogonoduct. bryozoans, and some other invertebrates. see protonephromixium, metanephromixium, mixo- nephridium. nerve pentagon (ECHINOD) The nerve ring around the mouth. nephropore n. [Gr. nephros, kidney; poros, pore] (ARTHRO: nerve ring Any ring of nerve fibers, may be around the mouth, Crustacea) The elevated opening of the antennal gland on esophagus, anus, bell margin, etc. see circumesophageal the ventral surface of the coxa of the antenna. commissure. nephrostomal lips (ECHI) The -like tissue surrounding the nerve root That part of the nerve close to its origin from a nephrostome; may be inconspicuous, expanded, or leaf- ganglion, cord or brain; may be just inside or outside of the like, or extended into long threads that may be spirally ganglion, etc. coiled. nervicole, nervicolous a. [L. nervus, nerve; colere, to in- nephrostome n. [Gr. nephros, kidney; stoma, mouth] The habit] Living on or in leaf veins. coelomic opening of a nephridium. nervous a. [L. nervus, nerve] Pertaining to nerves; restless or nepioconch n. [Gr. nepios, infant; konch, shell] (MOLL: Bival- impulsive behavior as in nervous movements. via) The first part of the dissoconch, when separated by a nervous system A system of nerves with which an organism discontinuity. adapts to its environment. nepionic a. [Gr. nepios, infant] Pertaining to very young; nervulation see venation postembronic larva; stage of development succeeding the nervules see nervures embryonic. nervures n. [L. dim. nervus, nerve] (ARTHRO: Insecta) 1. The nepionic constriction (MOLL: Cephalopoda] In a nautiloid tubular wing veins. 2. Branches of the tracheal system. shell, a definite growth discontinuity of the shell micro-or- namentation thought to correspond to eclosion from the nesium n.; pl. nesia [Gr. nesion, an islet] (ARTHRO: Insecta) egg. In scarab larvae, one or two sclerotized projecting marks between the inner end of the dexiotorma and crepis; nepionotype n. [Gr. nepios, infant; typos, type] The type when two are present, termed nesium externum and ne- larva of a species. sium internum; chitinous plate of Hayes. NEPO virus Referring to NEmatode-transmitted, POlyhedral- nest n. [A.S. nest] (ARTHRO: Insecta) A dwelling of social in- shaped viruses. see NETU virus. sects in which young are raised and reproductive females neritic zone The region of shallow water over the continental lay eggs; may be a burrow or hollow in soil, log, etc., or be shelf that is subdivided into supratidal (wave splash area), constructed of materials brought to the site, or materials intertidal (littoral), and subtidal regions. elaborated by the individuals in the colony. 607 608 Maggenti and Gardner On line Di ctio nar nestlers n.pl. [A.S. nestlian, to build a nest] (MOLL: ) neuration see venation y of Inv Clams nestling in cavities or concealment in clay or among erte neurilemma see Schwann cell bra dead shells that occasionally produce variations in shell te Z ool shape. neurite see axon ogy nest odor (ARTHRO: Insecta) In social insects, the distinctive neurobiotaxis n. [Gr. neuron, nerve; bios, life; taxis, ar- odor of a nest that enables its inhabitants to distinguish the rangement] 1. The hypothetical migration of nerve cells nest from those belonging to other colonies or the sur- and ganglia toward regions of maximum stimulation during rounding environment; hive aura/odor. see colony odor. phylogeny. 2. In , tendency of nerve cells to migrate toward the source of their stimuli. nest parasitism (ARTHRO: Insecta) In Isoptera, one species of termite that lives on the carton walls of the nest of the host neuroblast n. [Gr. neuron, nerve; blastos, bud] (ARTHRO: In- species. secta) In embryology, the inner layer of ectodermal cells that forms the nervous tissue. see dermatoblasts. nest robbing see cleptobiosis neurocirrus n.; pl. -ri [Gr. neuron, nerve; L. cirrus, curl] NETU virus Referring to NEmatode-transmitted, TUbular- (ANN: Polychaeta) Cirrus normally on the lower edge of the shaped viruses. see NEPO virus. neuropodium. neurocyte n. [Gr. neuron, nerve; kytos, container] The cell nettle cells see nematocysts body of a neuron; the nerve cell; cyton. neuraforamen n. [Gr. neuron, nerve; L. foramen, hole] (AR- neurofibrils n.pl. [Gr. neuron, nerve; L. dim. fibre, thread] THRO: Insecta) The foramen through which the nerve cord Fine fibers running longitudinally in axons and dendrites passes when it is separated from the occipital foramen. and through the body of the neuron. neural a. [Gr. neuron, nerve] Pertaining to the nerves or nerv- neurogenic a. [Gr. neuron, nerve; gennaein, to produce] 1. ous system of an organism. Forming nervous tissue. 2. Stimulating nervous for neural arc Simple receptor-effector nerve circuit. certain muscular or glandular reactions. see myogenic. neural canal (ARTHRO: Insecta) The incomplete canal on the neuroglia n.pl. [Gr. neuron, nerve; glia, glue] Nonnerve cells floor of the meso- and , formed by fusion of in the brain or ganglia; glia; glial cells; gliacytes. apodemes; functioning in the reception and protection of neurohemal organs (ARTHRO: Insecta) Organs involved with the ventral nerve cord and for attachment of muscles. the release of products of neurosecretory cells into the neural groove (ARTHRO: Insecta) The median ventral groove, hemolymph; corpora cardiaca best developed though less extending the entire length of the embryo, between the conspicuous ones make up the perisympathetic system as- neural ridges. sociated with the ventral nerve cord. neural lamella The noncellular outer covering of the central neurohormone n. [Gr. neuron, nerve; hormaein, to excite] A nervous system consisting of mucopolysaccharides and produced by neurosecretory cells. mucoproteins with collagen-type fibrils in the outer part of neurohumor see neurotransmitter this layer. neuroid transmission Arousal activity by cells other than neural ridges (ARTHRO: Insecta) In embryology, the two lon- nerve cells. gitudinal ventral ridges that contain the lateral cords of the neurolemma see Schwann cell neuroblasts. neuromere n. [Gr. neuron, nerve; meros, part] (ARTHRO: In- 609 610 Maggenti and Gardner On line Di ctio nar secta) Any of the transitory segmental elevations in the dition] Organisms livingy toofgether with no mutual harm or Inv wall of a developing embryo. benefit; hamabiosis. erte bra te Z neuron n. [Gr. neuron, nerve] A nerve cell. neutral synoekete (ARTHRO: Insecta) An oinosl ect living on the ogy neurone see neuron refuse of a host colony but providing little in return. neuropile n. [Gr. neuron, nerve; pilos, felt] The central part, new name A replacement name for an available name; nomen or mass of different axons within a ganglion; neuro- novum. spongium. niche n. [L. nidus, nest] A position or occupation filled by an neuroplasm n. [Gr. neuron, nerve; plasma, formed or molded] organism in the food-web of a . Cytoplasm of neurons. nictation see negative geotropism neuropodium n. [Gr. neuron, nerve; pous, foot] (ANN: Poly- nictitant a. [L. nictare, to wink] An ocellus bearing a lunate chaeta) The ventral division of the parapodium, supported spot. internally by one or more chitinous rods or aciculae. Any of various structures that secrete a neuropore see trichopore capsule or covering material for an egg or egg masses. Neuropteroidea see Holometabola nidicole a. [L. nidus, nest; colere, to dwell] Pertaining to an neuropterous a. [Gr. neuron, nerve; pteron, wing] (ARTHRO: organism that spends much of its life in the nest of its host. Insecta) Pertaining to the order Neuroptera. nidificant a. [L. nidus, nest; facere, to make] Building a nest. neurosecretory cells (ARTHRO: Insecta) Cells found in the nidifugous a. [L. nidus, nest; fugere, to flee] Departing the ganglia of the central nervous system that secrete hor- nest soon after birth. mones which act directly on effector organs or on other en- nidus n.; pl. nidi [L. nidus, nest] 1. A group of regenerative docrine organs. cells; a cell-group. 2. A location for the natural deposit of neurospongium see neuropile eggs; a hatching place. 3. The specific locality of a disease, neurosynapse see synapse resulting from a combination of ecological factors that favor the disease organism. 4. (ARTHRO: Insecta) Regenerative neurotransmitter n. [Gr. neuron, nerve; L. trans, across; cells that replace the midintestinal cells used up during mittere, to send] A chemical secreted at nerve endings to holocrine . transmit a nervous impulse across a synapse; neurohumor. niger n. [L. niger, black] Black; glossy black. neurotropic a. [Gr. neuron, nerve; tropos, turn] Having an affinity for nervous tissue. nigerrima a. [L. niger, black; -rimus, superlative ending] Very black. neurotubules n. [Gr. neuron, nerve; L. dim. tubus, tube] Microtubules in nervous tissue. nigrescent a. [L. nigrescens, to grow black] Turning black; blackish. neuston n. [Gr. neustos, able to swim] Small organisms that float or swim in or on the surface film of water. see nisto n. (ARTHRO: Crustacea) In Decapoda, the postlarval stage seston. of Scyllaridae and Palinuridae; pseudibacus; puerulus. neuter n. [L. ne, not; uter, either] 1. Sexless. 2. A sterile or- nitid, nitidus a. [L. nitidus, shining] Glossy; shining; brilliant; ganism. 3. A non-fertile mature female. lustrous. neutralism n. [L. ne, not; uter, either; ismus, denoting a con- nitrate n. [Gr. nitron, native soda] A salt or ester of nitric acid (HNO3 ). 611 612 Maggenti and Gardner On line Di ctio nar nitrite n. [Gr. nitron, native soda] A salt or ester of nitrous nodulus n. [L. dim. nodus, ykonfob] (ANN) An enlarged region on Inve acid (HNO2 ). a crotchet chaeta at about midlretnebgth. rate nitrogen n. [Gr. nitron, native soda; gennaein, to produce] A nodus n. [L. nodus, knob] (ARTHRO: InsecZtoao) 1. In Hymenop- log colorless, odorless gas that constitutes about four-fifths of tera Ichneumonidae, a dorsal prominence ony the tip of the the atmosphere. ovipositor, shortly before the . 2. In Odonata, a strong nitrogen cycle Inorganic nitrogen incorporated into organic cross vein near the middle of the costal border of the wing. nitrogen in living organisms and returned to inorganic ni- nomadism n. [Gr. nomas, roaming] (ARTHRO: Insecta) Fre- trogen by breakdown of the organic on death of quent movement by a colony from one site to another. the living organisms. nomenclator n. [L. nomen, name; calare, to call] A nomen- nitrogenous a. [Gr. nitron, native soda; gennaein, to produce] clatural book containing a list of scientific names, not for Pertaining to, or containing nitrogen. taxonomic purposes. nits n.pl. [A.S. hnitu, egg of louse] (ARTHRO: Insecta) In Si- nomenclature n. [L. nomen, name; calare, to call] In biology, phunculata, the eggs; particularly when cemented to hair. a system of names for biological units. niveous a. [L. niveus, snow] Resembling the color of snow. nomen conservandum A name preserved by action of the nocturnal a. [L. nocturnus, of the night] Occurring or per- International Commission on Zoological Nomenclature and formed at night. see diurnal, crepuscular. placed on the appropriate official list. nocturnal eyes (ARTHRO: Chelicerata) The pearly white eyes of nomen dubium The name of a nominal species that lacks Arachnida. available evidence so as to permit recognition of the zoo- logical species to which it was applied. nodal furrow (ARTHRO: Insecta) In Odonata, a transverse su- ture of the wing, beginning at the costal margin corre- nomen inquirendum The scientific name is subject to investi- sponding to the nodus and extending toward the inner gation. margin; costal hinge. nomen novum see new name node n. [L. nodus, knob] 1. A knob or swelling. 2. (BRYO) A nomen nudum A published binominal without an adequate de- place of articulation in a colony. scription, definition or illustration to permit its official nodicorn a. [L. nodus, knob; cornu, horn] (ARTHRO: Insecta) adoption. Having antennae with joints swollen at the apex. nomen oblitum No longer in effect in ICZN after 1973; a nodiferous a. [L. nodus, knob; fero, bear] Having or bearing name that has not been used in the primary zoological lit- nodes. erature for 50 years; a forgotten name. nodiform a. [L. nodus, knob; forma, shape] In the form of a nomen Any named taxon, objectively defined by its knob or knot. type, whether valid or invalid. nodose a. [L. nodus, knob] With small knotlike protuberances. nominalism n. [L. nomen, name; ismus, denoting a condition] Doctrine of nominalists denying the existence of universals, nodular a. [L. dim. nodus, knob] Having small knobs or nod- and emphasizing the importance of man-given names for ule-like projections. the grouping of individuals. nodular sclerite see epaulett nominate a. [L. nomen, name] Pertaining to a subordinate nodule n. [L. dim. nodus, knob] A swollen knob-like structure. taxon that contains the type of the subdivided higher taxon and bears the same name as the original parent taxon. 613 614 Maggenti and Gardner On line Di ctio nar noncelliferous side of colony (BRYO: Stenolaemata) The re- notal comb see genal comybof Inv verse or back side of the colony. erte notate a. [L. nota, mark] Marked by sbpraots or depressed marks. te Z noncellular outgrowth A cuticular prominence of the body- ool notation n. [L. nota, mark] The method of idoegnytifying charac- wall. ters by a system of numbers, letters or ratios. noncoelomate see acoelomate notaulix n.; pl. -lices, [Gr. notos, back; L. aulix, furrow] (AR- non-congression n. [L. non, not; congressus, meeting] Chro- THRO: Insecta) One of a pair of grooves on the mesoscu- mosomes not pairing on the spindle equator. tum, from the front margin to one side of the midline and non-conjunction n. [L. non, not; cum, with; junctus, joined] extending backward; divides the mesoscutum into 3 parts: Absence of meiotic chromosome pairing. a median lobe between the notaulices and a lateral lobe on each side (parapsides). nondimensional species The concept of a species character- ized by the noninterbreeding of two coexisting demes, un- notch n. [ME. nock, a notch] (MOLL: Gastropoda) A break or complicated by space and time. irregularity in the , denoting the position of the . nondisjunction n. [L. non, not; disjunctus, unyolked] The fail- ure to separate of paired chromosomes during . notched a. [ME. nock, a notch] Nicked or indented; usually of a margin. non-essential amino acids Amino acids that can be synthe- sized by animals and not required in their diet. notocephalon n. [Gr. notos, back; kephale, head] (ARTHRO: Insecta) 1. In Notonectidae, the dorsal view of the head. 2. nonincubatory oysters (MOLL: Bivalvia) Oysters that do not (ARTHRO: Chelicerata) In Arachnida, the dorsal shield of the incubate their larvae. prosoma. non-medullated nerve A nerve fiber lacking a myelin sheath; notocirrus n. [Gr. noton, back; L. cirrus, curl] (ANN: non-myelinated. Polyuchaeta) Cirrus of the notopodium. nonsense codon see nonsense notodeltidium see chilidium nonsense mutation A mutation that changes a coding triplet notodont a. [Gr. notos, back; odous, tooth] (ARTHRO: Insecta) into a triplet that codes for no amino acid and terminates Pertaining to larval Notodontidae with a variously humped the polypeptide chain. dorsal surface. normalizing selection The removal of all alleles that produce Notogaea n. [Gr. notos, back; ge, earth] The zoogeographical deviations from the normal (average) of a area including Australia, New Zealand and Pacific Ocean population by selection against all deviant individuals. Islands regions. nosogenic a. [Gr. nosos, disease; gennaein, to produce] notogaster n. [Gr. noton, back; gaster, belly] (ARTHRO: Cheli- Causing disease; pathogenic. cerata) The posterior dorsal opisthosomatal shield. nosography n. [Gr. nosos, disease; graphos, writing] A branch notonectal a. [Gr. notos, back; nektos, swimming] Swimming of dealing with the description of diseases. on the back. nota pl. of notopleura n.pl.; sing. notopleuron [Gr. notos, back; pleu- notacoria n. [Gr. notos, back; L. corium, leather] (ARTHRO: ron, side] (ARTHRO: Insecta) In Diptera, a sometimes Insecta) A membranous area separating the pleuron and sunken, triangular area on the thoracic dorsum, at the lat- notum in the thorax; sometimes reduced to a . eral end of the transverse suture, behind the humerus. notopleural a. 615 616 Maggenti and Gardner On line Di ctio nar notopleural bristles (ARTHRO: Insecta) In Diptera, bristles lo- Branchiopoda, a sensoryyoforgan on the upper side of the Inv cated in a small triangular area, one on each corner of the cephalon. 3. (SIPUN) Ciliated eertpeidermal cells at the mid- bra notum just above the anepisternum or mesopleura; be- dorsal edge of the oral disc; believedtetoZ be sensory. ool ogy tween the humeral and wing base. nuchal papilla (ANN: Polychaeta) Small sensory papilla at the notopleural suture (ARTHRO: Insecta) A suture between the base of the prostomium; cirrus. notum and the pleural sclerites. nuchal tentacles (PLATY: Turbellaria) In Polycladida, tentacles notopodium n. [Gr. notos, back; pous, foot] (ANN: Polychaeta) well set back from the anterior part of the body. The dorsal or upper division of the parapodium, supported nuclear envelope Double layered membrane separating the internally by one or more chitinous rods, or aciculae. nucleoplasm from the cytoplasm; nuclear membrane. notopterale n. [Gr. notos, back; pteron, wing] (ARTHRO: In- nuclear plate A metaphase or equitorial plate. secta) The first axillary sclerite of a wing. nuclear sap see nucleoplasm notoseta n. [Gr. notos, back; L. seta, bristle] (ANN) Seta origi- nating on the notopodium. nuclear whorls (MOLL: Gastropoda) The whorls of the proto- conch that emerges from the egg. nototheca n. [Gr. notos, back; theke, case] (ARTHRO: Insecta) That region of a pupa covering the dorsal surface of the nucleate a. [L. nucleus, kernel] Having a nucleus. abdomen. nucleic acids Polymers of nucleotides that are active in in- notothyrium n. [Gr. notos, back; thyrion, door] (BRACHIO) The heritance as genes, plasmids, etc. triangular notch in the dorsal , when present, open to nuclei of Semper (ARTHRO: Insecta) The nuceli of the crystal- the facilitating pedicle exit, usually closed off line cone cells. from the hinge plate by the chilidium. see delthyrium. nucleolar chromosome Any chromosome with a nucleolar or- notum n. [Gr. notos, back] 1. (ARTHRO: Crustacea) The ganizer. shrimplike decapod posterior part of the dorsal carapace. 2. nucleolar organizer Chromosome region that is active in nu- (ARTHRO: Insecta) The dorsal surface of a body segment, cleolus formation. particularly of the thoracic segment. notal a. nucleolinus n. [L. dim. nucleus, kernel] A small granule within nucha n. [ML. nucha, neck] The upper surface of the neck con- the nucleolus. necting the head and thorax. nuchal a. nucleolonema n. [L. dim. nucleus, kernel; Gr. nema, thread] nuchal caruncle (ANN) A sensory organ on the prostomium, or Filamentous structures within the nucleolus of all cells. extending posteriorly in the form of a ciliated ridge or groove. nucleolus n. [L. dim. nucleus, kernel] Small, dense, more or less spherical bodies in the nucleus of cells associated with nuchal cavity (MOLL: Gastropoda) In Patellacea, the enlarged the nucleolar organizer. portion of the pallial cavity above the head. nucleoplasm n. [L. dim. nucleus, kernel; Gr. plasma, formed nuchal cirrus see cirrus or molded] The protoplasmic fluid contained in the nucleus. nuchal constriction (MOLL: Cephalopoda) In most Sepiidae nucleoplasmic index The ratio of nuclear volume to cyto- and Teuthoidea and a few Octopodidae, the separation or plasmic volume; seems to trigger cell division; nucleoplas- constriction between the head and body or neck. mic ratio. nuchal organ(s) 1. (ANN: Polychaeta) A pair of ciliated sensory nucleoprotein n. [L. dim. nucleus, kernel; Gr. proteios, pri- pits or slits in the head region. 2. (ARTHRO: Crustacea) In 617 618 Maggenti and Gardner On line Di ctio nar mary] A compound of and . nutricial castration, castray toifon nutriciale (ARTHRO: Insecta) Inve nucleoside n. [L. dim. nucleus, kernel] Compounds derived by In , the conditionrteobf undeveloped gonads in rate hydrolysis of nucleic acids or nucleotides consisting of a young adult females due to devoting itZsoeolf to nursing larval log purine or pyrimidine base linked to ribose or deoxyribose. forms instead of herself taking on the nutriytion necessary for the reproductive form. see alimentary castration. nucleotide n. [L. dim. nucleus, kernel] Unit of the DNA and RNA molecules, including phosphoric acid, a purine or nutricism n. [L. nutrix, nurse] A symbiotic relationship in pyrimidine base, and a ribose. which one partner obtains all the benefits. nucleus n.; pl. -lei [L. nucleus, kernel] 1. A spheroidal struc- n. [L. nutrire, to feed] The ingestion, digestion and ture present in a cell containing the chromatin. 2. (MOLL: assimilation of food substances that includes their distribu- Gastropoda) The earliest-formed part of the shell, or oper- tion within the organism, as well as the and culum, of a . elimination of waste products. nudibranchiate a. [L. nudus, naked; branchiae, gills] nyctipelagic a. [Gr. nyktos, night; pelagos, sea] Coming to (BRACHIO) Having the gills uncovered and not protected by the water surface only at night. a shell or membrane in the brachial chamber. nymph n. [Gr. nymphe, bride] 1. (ARTHRO: Chelicerata) The nudum n. [L. nudus, naked] (ARTHRO: Insecta) A small bare, immature stage of Acari and Ixodoidea with a full comple- sensitive portion of a butterfly antenna. ment of legs; an instar. 2. (ARTHRO: Insecta) An immature stage that does not have a pupal stage. 3. (MOLL: Bivalvia) nulliplex a. [L. nollus, none; plectare, to weave] A polyploid see nympha. having all genes for a particular recessive character. nympha n.; pl. -phae [Gr. nymphe, bride] 1. (ARTHRO: Cheli- numerical phenetics The hypothesis that relationship be- cerata) In Acari, sclerites beneath the epigynium. 2. (MOLL: tween organisms can be determined by a calculation of an Bivalvia) The immersed area behind the that overall, unweighted similarity value. strengthens the margin to which the is attached, numerical Numerical evaluation of similarity be- or reinforcement for the normal hinge structure; ligament tween taxonomic units and grouping of these units into fulcrum; sometimes nymph. higher taxa on the basis of their affinities; taxometrics. see nymphal phase (ARTHRO: Chelicerata) The second or third taxonomy. phase of postembryonic development; in Acari with six sta- nuptial flight (ARTHRO: Insecta) In Hymenoptera, the mating ses, the third phase comprised of proto-, deuto- and trito- flight of winged males and females. nymphs. nurse cells 1. Cells of developing oocytes that provide material nymphipara a. [Gr. nymphe, bride; L. parere, to beget] (AR- for further growth; trophocytes. 2. (ARTHRO: Insecta) In THRO: Insecta) Bearing live young in an advanced stage of some species, the nurse cells synthesize nucleic acids and development. see pupipara. possibly protein and supply them to the oocyte via inter- nymphochrysalis n. [Gr. nymphe, bride; chrysallis, gold col- cytoplasmic connections. 3. (NEMATA) A specialized plant ored pupa] (ARTHRO: Chelicerata) In chigger mites, a non- response to feeding sessile forms, characterized by special feeding, prenymph; a calyptostasic protonymph. feeding cells around the nemas' head that are not subject to necrosis; giant cells. 4. (PORIF) The archaeocytes. nymphoid a. [Gr. nymphe, bride; eidos, form] (ARTHRO: Cheli- cerata) Nymphal phase instars that cannot be homologized nutant a. [L. nutare, to nod] Nodding; drooping; having a tip with nymphal instars of other species. bent horizontally. nymphoid reproductive (ARTHRO: Insecta) A neoteinic repro- 619 Maggenti and Gardner

ductive with wing buds; a second-form reproductive; sec- ondary reproductive; a brachypterous neoteinic. nymphosis n. [Gr. nymphe, bride] The process of transforming into a nymph or a pupa.

Copyright ©2005 Armand R. Maggenti and Scott Gardner.