Leptogenys antillana

This species is endemic to Hispaniola, and probably restricted to the Dominican Republic as suitable forest on the Haitian side is quite diminished (Lattke 2012). Bill Brown collected specimens in the Dominican Republic from under a rock in a disturbed area (coffee).

Identification
A member of the antillana species group. L. antillana is perhaps mostly closely related to Leptogenys reggae, another Caribbean endemic (Jamaica), on account of similarities in head shape, eye shape and its position on the head, and broad median clypeal lobe with a setae at the apex. The clypeal setae may be absent in some specimens.

Distribution
A Hispaniola endemic.

Distribution based on Regional Taxon Lists
Neotropical Region: Dominican Republic, Greater Antilles, Haiti.

Castes
Queen and male are unknown.

Nomenclature

 *  antillana. Leptogenys (Lobopelta) antillana Wheeler, W.M. & Mann, 1914: 14, fig. 5 (w.) HAITI. See also: Lattke, 2011: 146.

Lattke (2011) - Head subquadrate in full-face view, median clypeal lobe broadly triangular, apex bluntly pointed with median seta; compound eye weakly convex, its length close to one-fourth that of lateral cephalic margin, eye laterally placed in cephalic mid-distance; mesonotum arched, 5 x wider than long; petiole subquadrate in lateral view, anterior margin vertical, shorter than posterior margin.

Worker
Length 4.5-5.5 mm.

Body slender. Head about one and one-third times as long as broad, a little broader in front than behind, with rather straight sides and posterior border. Eyes small, shorter than their distance from the anterior corners of the head. Mandibles narrow but with distinct apical and basal borders. Clypeus very strongly carinate, with an anterior, median, beak-like point, filling the space between the mandibles when they are closed. Antennae slender; scapes extending a little more than their greatest diameter beyond the posterior border of the head; funicular joints 1-5 decidedly longer than broad, the second longest, joints 6-10 only slightly longer than broad. Thorax in front as broad as the head, pronotum as broad as long, meso- and epinotum together longer than the pronotum, in profile with straight dorsal surface about twice as long as the declivity which is feebly convex. Petiole from above 1.5 times as long as broad, twice as broad behind as in front, the node laterally compressed, in profile as high as long, as high in front as behind, evenly rounded above, with short, abrupt, rounded anterior and posterior declivities. Gaster and legs slender.

Smooth and shining. Mandibles with a few coarse punctures along their internal borders.

Hairs whitish, short, suberect or reclinate, not very abundant on the body, more abundant and shorter on the scapes and legs.

Black; mandibles, funiculi, bases and tips of scapes, tarsi, knees, tips of tibiae and tip of gaster red or reddish brown.

Lattke (2012) provided a more expansive description: Metrics (n = 3): HL 0.65-0.68; HW 0.67-0.70; ML 0.43-0.48; EL 0.17-0.18; SL 0.84-0.89; PW 0.57-0.60; WL 1.42-1.47; PH 0.52-0.57; PL 0.57-0.58; DPW 0.37-0.42 mm. CI 1.00-1.03; MI 0.64-0.71; OI 0.24-0.26; SI 1.25-1.29; LPI 0.91-0.97; DPI 0.65-0.71.

Head subquadrate in full-face view, slightly wider anterad than posterad, posterior and lateral margins weakly convex; median clypeal lobe broadly triangular, apex bluntly pointed, median seta present or absent; lateral clypeal lobe lamellate, little expanded, convex towards median lobe. Compound eye weakly convex, its length close to one-fourth that of lateral cephalic margin, eye laterally placed in cephalic mid-distance; mandible elongate, basal and external margins mostly parallel, weakly widening apicad, basal margin convex with 3 – 5 thickened hairs basad, basal tooth developed as distinct denticle, masticatory margin edentate, concave; dorsal surface mostly smooth and shining with sparse punctate; PF: 4,3. Cephalic dorsum mostly smooth and shining with scattered piligerous punctulae; clypeus with weak rugulae and oblique striae mostly mesad, smoother close to median lobe and laterad. Scape surpasses posterior cephalic border by under one-fourth its length; third antennal segment 2 x longer than apical width; antennal segments II and IV each longer than half length of segment III. Scape mostly smooth and shining with abundant piligerous punctulae.

Mesosoma with promesonotum forming single broad convexity in lateral view, metanotal groove modestly impressed, dorsal propodeal margin broadly convex, twice longer than declivitous margin; declivity broadly convex, unarmed, without lobe or denticle. Mesosoma mostly smooth and shining with sparse piligerous punctae; mesometapleural suture well impressed, rugulose; mesopleuron elongate, rectangular; metapleuron with sparse striae posteroventrad; propodeal spiracle oval, posterolaterally facing; propodeal declivity wider than long, convex and curving continuously onto lateral and dorsal propodeal faces; declivity weakly colliculate with few transverse striae posterad. Mesonotum arched, 5 x wider than long; metanotal groove smooth; metapleural-propodeal suture absent.

Petiole subquadrate in lateral view, anterior margin vertical, shorter than posterior margin, anterodorsal margin convex, node highest posterad, posterior margin broadly convex. Node elongate and triangular in dorsal view, lateral margin broadly concave, width of anterior margin less than half width of posterior margin, anterior margin convex, posterior margin weakly convex to straight. Subpetiolar process shaped as posteroventrally bent lobe. Node mostly smooth and shining with some rugulae between petiolar spiracle and ventral process. Anterior margin of third abdominal segment mostly straight and posteriorly inclined, dorsal margin mostly straight with posterior convexity; constriction between abdominal segments III and IV moderate; gaster smooth and shining with sparse piligerous punctulae. Coxae and rest of legs mostly smooth and shining; mesotibial apex with single external seta, pro- and metatibia without setae; body with sparse subdecumbent to erect hairs, no appressed pubescence. Mandible, antenna, apex of median clypeal lobe, legs, and gaster ferruginous brown; rest of body dark brown.

Type Material
Described from seven specimens taken at Milot, Diquini and Petionville.

The type series consists of 4 workers on a single pin with two cardboards, each with two workers glued to it.

Additional References

 * [[Media:Lattke 2011.pdf|Lattke, J. E. 2011. Revision of the New World species of the genus Leptogenys Roger (Insecta: Hymenoptera: Formicidae: Ponerinae). Arthropod Systematics and Phylogeny 69:127-264. [2011-12-13] PDF]]