Redescription of Aspisoma Trilineata (Say) Comb
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464 Florida Entomologist 86(4) December 2003 TAXONOMY AND BEHAVIOR OF PHOTURIS TRIVITTATA SP. N. (COLEOPTERA: LAMPYRIDAE: PHOTURINAE); REDESCRIPTION OF ASPISOMA TRILINEATA (SAY) COMB. N. (COLEOPTERA: LAMPYRIDAE: LAMPYRINAE: CRATOMORPHINI) JAMES E. LLOYD1 AND LESLEY A. BALLANTYNE2 1Department of Entomology and Nematology, University of Florida P.O. Box 110620, Gainesville, FL 32611-0620, USA 2School of Agriculture, Charles Sturt University, P.O. Box 588, Wagga Wagga, N.S.W. 2678, Australia ABSTRACT Photuris trilineata (Say) is assigned to Aspisoma Laporte, and the type female is re- described. Photuris trivittata sp. n. is described from behavior voucher specimens, and be- havioral data are presented and discussed. Aspects of abdominal segmentation and aedeagal structure of Aspisoma and Photuris are described. Key Words: flash patterns, ecology, predation, neotropical fireflies RESUMEN Photuris trilineata (Say) es asignado al Aspisoma Laporte, y el tipo de hembra es redescrito. Photuris trivittata sp. n. se describe de acuerdo a los comportamientos de los especímenes comprobantes y los datos de los comportamientos son presentados y discutidos. Aspectos so- bre la segmentación abdominal y el edeago del Aspisoma y Photuris son descritas. Translation provided by author. Say (1835) described Lampyris trilineata from discussed separately below. Descriptions are or- a female now housed in the Museum of Compara- dered so that features on the dorsal surface are tive Zoology at Harvard University. Olivier (1886) described in sequence from the anterior to poste- assigned L. trilineata to Photuris but did not ex- rior end, and then the ventral surface is described amine the type and appears to have based his ac- in the same manner. This facilitates handling un- tion on the similarity of the described color der the microscope. Length, measured as median patterns. Lloyd tentatively assigned the behavior length of pronotum plus maximum length of an voucher specimens included here to Photuris tri- elytron, is sometimes a misleading representation lineata (Say), but after locating and examining since the pronotum droops in pinned specimens, the type female of L. trilineata he determined and the specimen will always appear shorter than that trilineata should be assigned to Aspisoma the figure given. The length of the head, which and that his specimens were of a new species. may protrude to a variable extent in males, is not Olivier’s collection in the Paris Museum was ex- included. Measurements (i.e., lengths) taken at amined by Ballantyne in November 1993. Oliv- the longest and widest areas respectively, such as ier’s methodical collection often reflects the pronotal width, greatest head width in anterior chronology of his published work, and standing in aspect, are used on a comparative rather than ab- the Olivier collection under Photuris trilineata solute basis (Lampyrids being soft bodied are sub- (Say) were specimens of Photuris which are con- ject to much distortion)—for example the distance specific with the specimens described below. between the antennal sockets is given as a func- Lampyris trilineata Say is assigned to Aspisoma; tion of the nearest convenient point of reference, Olivier’s firefly apparently has remained un- the width of an antennal socket. named, and is herein described as Photuris trivit- McDermott (1964) distinguished the Photuri- tata. JEL provided the biological data; LAB nae with a “membranous labrum arising from the provided the taxonomic framework. ventral surface of a strongly sclerotized clypeus.” The nature of the labrum was reinterpreted by Taxonomy John Lawrence (1987): in the cantharoids there is probably never a well-developed clypeus sepa- Taxonomic characters follow Ballantyne rated from the frons by a complete frontoclypeal (1987a, 2000) with exception of abdominal seg- suture. In most Lampyridae the labrum is at least mentation and aedeagal structures, which are slightly sclerotized and separated from the clypeus Lloyd & Ballantyne: Taxonomy and Behavior of Photurus trivittata 465 by a strip of membrane. The anterior strongly bear the spiracles which are covered by the lat- sclerotized plate on the Photurinae head is here eral tergal margins and difficult to see in pinned interpreted as the labrum. specimens; the light organ in males and females While specimens were still soft and flexible occurs in ventrites 6 and 7 (Figs. 3 and 4) but may many aedeagi were extruded by the collector be considerably retracted from the lateral areas (JEL), and remain attached to the specimen, usu- in females; depressions in lateral areas of ven- ally with the basal piece still encased between trites 6 and 7 probably house sense organs (Lloyd ventrite 9 and tergite 9 (the “aedeagal sheath” of & Ballantyne, pers. obs.); ventrite 8 is transverse, Ballantyne 1987a, b), and often hidden. Some about half as long and wide as 7, with the median aedeagi were removed and mounted on transpar- posterior margin emarginate; aedeagal sheath ent points, using transparent glue, and re- (= ventrite and tergite 9) when visible externally mounted beneath the specimen (specimens were is turned on its side; tergite 8 about as long as, but softened for 2-3 days in a humid atmosphere in an narrower than, tergite 7. airtight container with moist sand with a few The male Photuris abdomen (Fig. 15) has ven- drops of Lysol® to retard mold). trites 6 and 7 often medially emarginate posteri- The two specimens selected for scanning elec- orly; ventrite 8 always tapers posteriorly, is tron microscopy were dried pinned specimens usually about half as long as 7, although some- which had the aedeagus extended. They were times retracted beneath 7; the median posterior mounted on aluminum stubs using double sided margin of ventrite 7 always has a pointed projec- semitransparent tape and coated with gold in a tion of varying length; tergite 8 often has lateral Denton Vacuum Desk II Cold Sputter Etch Unit, margins reflexed; aedeagal sheath ventrite and and examined in a Hitachi 570 scanning electron lateral projections of aedeagus sometimes visible microscope at an accelerating voltage of 15 KV. behind ventrite 8. The female abdomen has light The operation was carried out as part of a class organs apparently contained in ventrites 6 and 7; exercise in the Department of Entomology and ventrite 8 tapers posteriorly and may be medially Nematology at the University of Florida in incised (Fig. 16). Gainesville, under the direction and assistance of Aedeagal structure. The aedeagus of Aspisoma Prof. Harvey Cromroy. The type female of Lampy- most closely approaches that of the Luciolinae ris trilineata Say was not dissected, and drawings (Ballantyne 1987a, b, 2000), in having a clearly represent the specimen in its actual state at the defined median lobe, lateral lobes (which may be time of examination. Specimens are currently slightly longer or shorter than the median lobe), housed in the JEL collection in Gainesville and an elongate well defined basal piece. The me- (JELC), or the Florida State collection of Arthro- dian lobe is elongate, slender, and often medially pods (FSCA). carinate along the dorsal surface; lateral margins Abdominal segmentation. Abdominal segmen- of the median lobe can expand and are variably tation is interpreted from Ballantyne (1987a, developed. Small hooks may arise from the inner 1992). Terminology of the ventral abdominal face of the lateral lobes and in A. physonotum plates has varied. Green (1956) used “sternite” for they engage against the median dorsal carina of the median half of each ventral segment in Photi- the median lobe (Ballantyne 1992). nus and considered the lateral area on each side The aedeagus of Photuris spp. consists of me- the pleurite, which is narrowly inflexed dorsally dian and lateral lobes and a basal piece, and and bears the spiracles. Crowson (1972) called the paired long slender processes extending from the ventral abdominal plates “ventrites” but (page 39) sides of the basal piece (Figs. 17 and 18). These referred the spiracles to the “inflexed edges of the pieces “splay” to varying degrees in pinned speci- sternal plates.” A refinement of the definition of mens, and the full extent of the basal piece is not the term “ventrite” in the Lampyridae was pro- always visible in specimens where the aedeagus posed (Branham & Archangelsky 2000). is still attached to the abdomen. The abdomen of Aspisoma and Photuris males Barber (1951) described the Photuris aedea- (Figs. 4 and 15) consists of 8 visible tergites, al- gus: “sides of the ‘basal piece’ are produced into though the first may be difficult to distinguish. long slender, clubbed, lateral processes extending Segments 2-8 are distinguishable ventrally. The beyond the apex of a slender median lobe”. McDer- light organs occupy the ventral plates of seg- mott (who completed Barber’s manuscript after ments 6 and 7. Ventrite 8 is well developed al- his death), included figures (Figs. 2 and 3) of Pho- though it is usually shorter than 7. Ventrite 9 turis lucicrescens aedeagus which was unlabeled (which surrounds the aedeagus) is usually visible but described in the text as having “the lateral externally, protruding beyond the posterior mar- lobes fuse with the dorsal surface of the median gin of ventrite 8, and completely covered dorsally lobe at about basal third, and are armed inter- by the relatively large tergite 8. nally opposite this point with a strong transverse The Aspisoma abdomen is broad, flattened, ta- ridge, which is sharply angulate at inner third”. pering at