Longitarsus alisonae, Clark & Lillrose & Belo Neto, 2013

Clark, Shawn M., Lillrose, Tiffany & Belo Neto, Luiz A., 2013, Leaf Beetles of the Cayman Islands (Coleoptera: Chrysomelidae), Insecta Mundi 2013 (279), pp. 1-41 : 23-24

Longitarsus alisonae , new species

( Figures 16, 36, 44)

Diagnosis. In this species, the hind femora are greatly enlarged, the basal tarsomere of each hind leg is about half as long as the hind tibiae, and the elytra are slightly truncate, leaving much of the apical abdominal tergite uncovered. This combination of characters distinguishes this species from all other chrysomelids known to occur in the Cayman Islands. Beyond the Cayman Islands, this species is quite similar to L. chlanidotus Blake , a species that was originally described based on material from Puerto Rico, Jamaica, and the Florida Keys. Longitarsus alisonae differs from L. chlanidotus in having a slightly smaller prothorax in comparison to the size of the body, in having more prominent elytral humeri, in having more of the apical abdominal tergite uncovered, and in having the elytra entirely pale or with at most the extreme sutural and lateral margins darkened (the elytra of many, but not all, specimens of L. chlanidotus have broad sutural and lateral dark markings).

Description of male. Body 1.6 mm long. Pronotum 1.2 times as wide as long. Elytra 2.1 times as long as wide, 3.0 times as long as pronotum.

Head pale brown; antennomeres 1-4 usually yellow, 5-11 dark brown; mandibles pale brown, darker at tip; maxillae with distal palpomeres darker brown than more basal palpomeres. Pronotum and scutellum yellowish brown, lighter in color than head. Elytra yellowish brown, lighter than pronotum, with suture narrowly darker. Venter with prothorax, mesothorax, and abdomen pale yellowish brown, with metathorax slightly darker. Legs pale yellowish brown, with distal tarsomeres of front and middle legs darker.

Head with surface of vertex impunctate, shining. Antennal (frontal) calli strongly delimited laterally, less distinctly defined posteriorly. Eyes oval, small, in frontal view separated from antennae by distance nearly equal to their individual width, in lateral view separated from base of mandible by about half their maximum diameter. Antennomeres 1 and 11 subequal in length, longer than others; 2 slightly swollen, shortest; 3 and 4 subequal in length; 5-10 subequal in length. Maxillary palpomere 2 distinctly swollen; palpomere 3 conical.

Pronotum rather strongly convex and rounded downwards at sides, narrow at base, gradually widening to post-apical angulations, thence abruptly narrowed to anterior margin; pronotal disc conspicuously, rather coarsely punctured, with punctures separated by distance about equal to their diameters. Scutellum subtriangular, obtusely angled behind.

Elytra very densely punctate basally, with punctures similar in size and separation to those of pronotum, distally more shallow, apically obsolete; shape strongly rounded downwards laterally; humeri well developed; epipleura facing subventrally, wide in basal half, thence strongly tapered apically; elytral apex truncate, leaving much of posterior abdominal tergite exposed. Hind wings well developed.

Ventral areas with pronotal hypomeron polished, vaguely alutaceous upon close examination; prosternum anterior to coxa about half as long as coxa; prosternal process between coxae about as wide as antennomere 3; procoxal cavities broadly open behind. Metasternum glabrous, polished. Abdomen glabrous, polished; terminal ventrite with quadrate apical lobe. Pygidium shallowly punctate, with interspaces alutaceous, with apex truncate. Metatibiae with stout row of spines along apical third of dorsal, outer edge; apical spur prominent. Aedeagus as in Figure 36.

Description of female. Color, form, and dimensions similar to those of male, but with differences as follow. Body 1.7 mm long; pronotum as long as wide; elytra 2.0 times as long as wide, 2.8 times as long as pronotum; pygidium and terminal ventrite each narrowed to subangulate apex; spermatheca as in Figure 44.

Material examined. Holotype: “ CAYMAN ISLANDS: Little Cayman , Coot Marsh, 27-V-2009, Thomas, Turnbow & Ball, blacklight trap ” (male, FSCA) . Paratypes: Cayman Islands , Grand Cayman, Governor Gore’s Pond, 28-V-2009, R. Turnbow (1 female, RHTC) ; Cayman Islands , Little Cayman, Coot Marsh, 27-V-2009, Thomas, Turnbow & Ball, blacklight trap (1 female, BYUC; 1 female, FSCA) .

Plant associations. Unknown.

Etymology. The species epithet of this taxon honors Alison Clark, daughter of the senior author.

Comments. As noted in the above diagnosis, this species is quite similar to L. chlanidotus . Among other things, the elytra of both species are slightly truncate, though less so in L. chlanidotus . In the original description of that species, Blake (1964) did not mention the slightly truncate elytra, nor did she clearly indicate this condition in her illustration. Nonetheless, our examination of material from Puerto Rico and the Virgin Islands attests to this character for the species. In addition to the specimens included in the type series of L. alisonae , we have also seen a single specimen (BYUC) from Jamaica that probably belongs to this new species.