Leptogenys toxeres

The specimens were taken from sifted litter containing leaf mold and rotten wood collected in a lowland forest.

Identification
Lattke (2011) - A member of the rufa species group. The sulci on the mesosomal dorsum are unique amongst the New World species, making it quite easy to determine.

Head subquadrate in full-face view, widest at cephalic mid-length; length of compound eye under one-fourth lateral cephalic margin, placed laterally on head; mesosomal dorsum shining, with abundant foveolae, each extending briefly with sulcus. Longitudinal sulci present on mesonotum and propodeal dorsum, radiating medially on pronotal discal area; petiolar node shaped as anteriorly inclined rectangle in lateral view.

Distribution based on Regional Taxon Lists
Neotropical Region: Costa Rica.

Castes
Male unknown.

Nomenclature

 *  toxeres. Leptogenys toxeres Lattke, 2011: 211, fig. 67 (w.q.) COSTA RICA.

Worker
Metrics, holotype (paratypes, n = 3): HL 1.11 (1.11–1.14); HW 0.83 (0.83–0.86); ML 0.61 (0.58– 0.61); EL 0.13 (0.13–0.15); SL 1.01 (1.01–1.01); PW 0.73 (0.71 – 0.73); WL 1.64 (1.67 – 1.75); PH 0.73 (0.73 – 0.78); PL 0.61 (0.58 – 0.63); DPW 0.58 (0.58 – 0.63) mm. CI 0.75 (0.75–0.76); MI 0.73 (0.68–0.73); OI 0.15 (0.15 – 0.18); SI 1.21 (1.18 – 1.21); LPI 1.21 (1.16 – 1.30); DPI 0.96 (0.96 – 1.04).

Head subquadrate in full-face view, widest at cephalic mid-length, lateral and posterior cephalic margins broadly convex, vertexal carina well developed, visible along all of posterior cephalic margin; median clypeal lobe triangular, width of base same as external width of antennal sclerites, apex bluntly angular to pointed, no apical setae. Lateral clypeal modest, widest and convex toward median lobe. Length of compound eye under one-fourth lateral cephalic margin, placed laterally on head, not more than 8 ommatidia in length; individual ommatidia distinct to indistinct on same eye, convexity of each ommatidia weak; oculomalar distance greater than eye length, eye in dorsal cephalic view with center equidistant from mandibular insertion and midpoint of lateral cephalic margin. Cephalic dorsum mostly smooth and shining, except for piligerous punctae, which become denser between eye and frontal carina, punctuate become smaller and sparse towards antennal fossa and clypeus, punctae deeper posterolaterally on cephalic dorsum, with brief shallow sulcus projecting anterad from each depression posterolaterad of eye. Ventral cephalic surface mostly smooth and shining with sparse piligerous punctae, each depression elongate, with transverse longitudinal axis. Scape surpasses posterior cephalic border by less than one-third its length, basal funicular segments slightly longer than wide, each segment wider apicad than basad, antennal segment III longer than either segment IV or V. Scape mostly smooth and shining with abundant punctulae. Mandible elongate, does not shut tight against clypeus, external and basal margins parallel-sided, basal margin broadly concave with 5 – 6 stiff hairs present next to median lobe; masticatory margin edentate except for apical tooth, mandibular dorsum mostly smooth and shining except for scattered piligerous punctae, and scattered, fine and brief longitudinal striae.

Mesosoma with broad and well-impressed metanotal groove in lateral view, pronotal margin anteriorly convex, dorsal margin weakly convex; mesonotum appears as small convexity; dorsal propodeal margin broadly convex, more than 2 × length of declivitous margin, declivitous margin straight, bluntly jagged, with blunt triangular tooth; dorsal and declivitous propodeal margins form obtuse angle. Pronotum mostly smooth and shining laterad, with punctae which become sparse and small posteroventrad, and deeper anterad; mesosomal sides mostly with oblique striae and rugulae, sculpturing strongest posteroventrad of meso- and metapleura, and posterad of propodeal spiracle. Propleuron mostly smooth and shining with weak transverse striae; mesometapleural suture well impressed; metapleural-propodeal suture present, propodeal spiracle broadly elliptical, facing posterolaterad. Mesonotum twice wider than long in dorsal view, metanotal groove scrobiculate; transverse flat area present posterad of metanotal groove; mesosomal dorsum shining, with abundant foveolae, each extending briefly with sulcus. Sulci longitudinal on mesonotum and propodeal dorsum, radiating medially on pronotal discal area; propodeal dorsum with weak, fine transverse striae; propodeal declivity flattened with transverse striae and laterally separated from rest of propodeum by low, blunt crest.

Petiolar node shaped as anteriorly inclined rectangle in lateral view; anterior margin straight, half the length of posterior margin; node highest posterad; dorsal margin straight; posterior margin straight to weakly concave. Subpetiolar process shaped as posteroventrally directed triangle. Node in dorsal view wider than long, slightly wider posterad than anterad; anterior margin broadly convex, posterior margin broadly convex. Cross-section of node at mid-length convex. Node with longitudinal sulci on dorsum, laterally with oblique sulci. Anterior margin of abdominal segment III vertical to weakly convex in lateral view, dorsal margin convex, constriction between abdominal segments III and IV well marked, scrobiculate. Gaster shining, abdominal tergites III and IV with punctae or foveolae with sulci, deepest and densest anterodorsad, shallower posterolaterad, punctae present on posterior tergites. Tibiae without apical setae. Head and body with abundant mostly subdecumbent to suberect pilosity, no appressed pubescence.Head, mesosoma, petiole and most of gaster brown; mandibles, antennae, legs and gastral apex ferruginous.

Queen
Metrics: HL 1.11; HW 0.81; ML 0.56; EL 0.15; SL 1.01; PW 0.68; WL 1.54; PH 0.73; PL 0.51; DPW 0.61 mm. CI 0.73; MI 0.69; OI 0.19; SI 1.25; LPI 1.45; DPI 1.20. Queen very much as worker except for more convex propodeal dorsum, more compressed petiolar node and larger gaster.

Type Material
Holotype worker. Costa Rica, Limón, 3 km SSE Cahuita, 9°43′N 82°50′W, 70 m, 24.xii.1983, P.S. Ward 6530-3. One worker deposited in. – Paratypes. Three workers, one queen from the same series as the holotype. One queen deposited in MCZC, one worker each deposited in, ,.

Etymology
The name alludes to the elongate and delicately arched mandible of the species. It is derived from the Greek for furnished with a bow.

References based on Global Ant Biodiversity Informatics

 * 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