Leptogenys melena

The type series nest was located beneath the bark of a dead tree on the ground, the ants proved to be fast runners as only a few could be caught as they fled into the surrounding litter. The type locality for this species is the Paria Peninsula, a humid, forested area that shares many faunal elements with the Orinoco Delta and southern Venezuela. (Lattke 2011)

Identification
Key to Leptogenys of the New World

Lattke (2011) - A member of the pusilla species group. Scape surpasses posterior cephalic border by almost one-fourth its length; funicular segments subcylindrical. Petiole subquadrate in lateral view with anterior margin shorter than either posterior or dorsal margin; anterior margin broadly convex, separated from broadly convex dorsal margin by sharp curve, posterior margin convex. Mesosoma mostly smooth; propodeal spiracle round. Head and mesosoma with blue iridescence.

Distribution based on Regional Taxon Lists
Neotropical Region: Venezuela.

Castes
Queens and males are unknown.

Nomenclature

 *  melena. Leptogenys melena Lattke, 2011: 194, fig. 48 (w.) VENEZUELA.

Worker
Metrics, holotype (paratypes, n = 4): HL 0.94 (0.95–0.97); HW 0.57 (0.58–0.60); ML 0.40 (0.38– 0.42); EL 0.15 (0.15–0.15); SL 0.82 (0.85–0.87); PW 0.52 (0.52 – 0.57); WL 1.34 (1.35 – 1.37); PH 0.48 (0.48 – 0.53); PL 0.47 (0.48 – 0.50); DPW 0.32 (0.33 – 0.35) mm. CI 0.61 (0.60 – 0.63); MI 0.71 (0.64 – 0.71); OI 0.26 (0.25 – 0.26); SI 1.44 (1.44–1.46); LPI 1.04 (1.00–1.10); DPI 0.68 ( 0.67 – 0.72).

Head rectangular in full-face view; posterior margin broadly convex, almost straight; lateral margin mostly straight, curving posterad; eye placed laterally on head, ocular mid-point is slightly anterad of mid-length of lateral cephalic margin; eye relatively flattened; anterolateral clypeal margin concave, lateral clypeal lobe discrete, small; median lobe triangular, apex acutely pointed, process longer than greatest diameter of scape. Cephalic dorsum mostly smooth and shining, with sparse punctulae, clypeus smooth to slight rugulose, with some oblique strigulae. Scape mostly smooth with abundant decumbent hairs, surpassing posterior cephalic border by almost one-fourth its length; antennal segment IV slightly shorter than III; width of fourth segment more than half its length, width of III twice its length. Funicular segments subcylindrical, without pronounced constriction between each. Mandibles close tight against clypeus when closed; mandible flattened, basal margin basally convex, apically concave; 2 setae present at base of basal margin; single preapical denticle present; external and internal mandibular margins sub-parallel; mandibular dorsum smooth with few punctae; PF: 4,4.

Mesosoma with promesonotal margin broadly convex in lateral view, separated by metanotal groove from broadly convex propodeal dorsal margin. Mesosoma mostly smooth and shining; mesopleuron, lower metapleuron, and propodeum posterad of spiracle with faint transverse to oblique strigae. Mesonotum transverse, wider than long in dorsal view, with sub-parallel anterior and posterior margins. Propodeal spiracle round, opening faces laterally. Mesometapleural suture well developed, metapleural propodeal suture wanting. Mesopleuron separated from mesosternum by low ridge. Propodeum with short triangular denticle, not longer than 5 diameters of spiracle. Mesosternum with transverse ridge that forms rounded lobe medially. Metasternum with similar ridge, but not as high and medial lobes not as blunt.

Petiole subrectangular in lateral view with anterior margin shorter than either posterior or dorsal margin; anterior margin broadly convex, separated from broadly convex dorsal margin by sharp curve, posterior margin convex; node mostly smooth and shining, lateral face with faint longitudinal striae ventrad, posterior face separated from rest by sharp curve. Petiolar node elongate in dorsal view, anterior margin convex, about half width of straight posterior margin; constriction between abdominal segments III and IV moderately developed. Scape, mesosoma, and abdomen brown; head slightly darker; funiculus, mandible, legs and gastral apex brownish yellow; head and mesosoma with blue iridescence. Procoxa smooth and shining laterally; apex of fourth protarsal segment with single pair of setae; mesotibial apex with single apical seta; posterior metacoxal swelling well developed.

Type Material
Holotype worker. Venezuela, Sucre, vía Las Melenas a Santa Isabel, ca. Cerro Humo, 10°42′N 62°38′W, 930 m, 9.v.1993, J. Lattke 1474. Deposited in. – Paratypes. Three workers from the same nest as holotype, deposited as follows: 1w, 1w , 1w.

Etymology
The species name alludes to a small village near the collection site for the ants.