Leptogenys tatsimo

Leptogenys tatsimoi s a humid forest dweller of southeastern Madagascar. The species nests in rotten logs and forages on the forest floor.

Identification
Rakotonirina and Fisher (2014) - Worker. Anterior border of medial clypeal lobe with anteriorly projecting, small peg-like setae from above much broader semi-translucent lamella; lamella width as great as minimum diameter of antennal scape; scape relatively long (SI 144–147), more than apical third portion extending beyond posterior cephalic margin. Mandible roughly broad and smooth apart from short striation and sparse punctures; blades strongly curved near base, increasing in width toward apical section. In dorsal view, dorsum of mesosoma consisting of four segments, with an additional suture between metanotal groove and propodeum.

Leptogenys tatsimo and Leptogenys manja look very similar, but L. tatsimo has a broader mandible, a conspicuous fringing lamella on the clypeus, and an additional suture between the metanotal groove and the propodeum in dorsal view (four apparent segments on the dorsum of the mesosoma). Leptogenys manja is characterized by the slender mandibular blades, a narrow, semi-translucent lamella on the clypeus, and three mesosomal segments in dorsal view.

Key to Malagasy Leptogenys

Distribution based on Regional Taxon Lists
Malagasy Region: Madagascar.

Nomenclature

 *  tatsimo. Leptogenys tatsimo Rakotonirina & Fisher, 2014: 101, figs. 49A, 51A, 109, 125 (w.) MADAGASCAR.

Worker
(3 specimens). HW: 1.53–1.68, HL: 1.90–2.06, CI: 81–82, SL: 2.25–2.44, SI: 144–147, PW: 1.23–1.31, WL: 3.46–3.54, PNH: 0.92–1.02, PNL: 1.01–1.07, PNW: 0.85–0.95, DNI: 84–88, LNI: 91–95.

In full-face view, head elongate and slightly increasing in width toward the front of eye; sides broadly convex. Eye somewhat protruding, position dividing lateral margin of head. Antennal scape particularly long, with more than one third of its length surpassing posterior cephalic margin. Anteromedian lobe of clypeus broadly angulate with a blunt apex, connected with generally convex lateral margin and bordered with wide, fringing, semi-translucent membrane. Mandible long and broad, strongly curved near base; gradually increasing in width, apical tooth obtuse; not capable of closing tightly against median lobe of clypeus if apices superimposed. In full-face view, hypostomal teeth not visible. With mesosoma in dorsal view, metanotal groove impressed, additional shallow and fine transverse sulcus present between metanotal groove and propodeum; in lateral view, propodeal dorsum roughly straight and elongate, joining distinctly short declivity in blunt angle. Petiolar node in profile more or less elongate, with anterior and posterior margin rounding to convex dorsal margin. Constriction between third and fourth abdominal segments strong. Mandible generally smooth apart from faint short striation and sparse punctures. Dorsum of head and mesosoma densely reticulate-rugose; propodeal declivity rugulose. Lateral portion of petiolar node reticulate-rugose, and dorsally finely microreticulate, with sparse large punctures. Body dorsum covered with standing hairs and pubescence. Color black; apex of appendages and extremity of gaster ferruginous-brown.

Type Material
Holotype worker: Madagascar, Toliara, Grand Lavasoa, 25.9 km W Tolagnaro, -25.0877, 46.749, 450 m, rainforest, ex rotten log, 30 Nov 2006 (B.L. Fisher et al.) collection code: BLF15384, specimen code: CASENT0122874. Paratypes: 4 workers, same data as holotype but specimen coded: CASENT0247279, CASENT0247280, CASENT0247281, CASENT0247282 (CASC,, ).