Leptogenys punctaticeps

Inhabits lowland forests in Costa Rica, Colombia and Panama.

Identification
Longino and Lattke (2004) - When mandibles are in their usual resting position, with tips crossed, they project beyond anterior border of clypeus, leaving a distinct gap; mandible slender, parallel sided in frontal view; clypeus reduced, leaving labrum largely exposed; hypostomal teeth reduced, barely or not visible in full-face view; head distinctly narrowed behind; face with large puncta (which may be dense or somewhat dispersed and shallow); compound eye large, diameter covering more than one third the length of the lateral cephalic margin; metanotal groove well impressed; propodeum unarmed; dorsal and posterior faces of petiole meeting at nearly a right angle, not or only weakly produced as a posteriorly directed tooth; posterior margin of node sinuous in lateral view; legs and scapes darker brown, not contrasting strongly with head and mesosoma.

A member of the unistimulosa species group.

Distribution
Costa Rica to northwestern Colombia. Costa Rica: Atlantic and southern Pacific lowlands Longino and Lattke (2004).

This taxon was described from Costa Rica. It is also known from Panama and northwestern Colombia.

Costa Rica
Longino and Lattke (2004), Lattke (2012) - The favored habitats for this species seem to be lowland forest, including open forest. According to the label some BCI specimens were taken with an isopod. I know this species from La Selva Biological Station and from Sirena in Corcovado National Park on the Osa Peninsula. At La Selva I know it from stray workers and males at blacklights. At Sirena I observed a colony or colony fragment. A tight column of 39 adults was moving along a trail. They stopped at one point, the column broke up, and individuals ran madly about in a small area. After about 10 minutes of this a less well defined column moved 1m away to a spot under a Cecropia leaf. They were carrying pupae and large larvae, and one worker was missing the gaster. Perhaps such a situation could have been the consequence of an army ant raid.

Nomenclature

 *  punctaticeps. Leptogenys punctaticeps Emery, 1890a: 62 (footnote) (w.) COSTA RICA. [Also described as new by Emery, 1894k: 49.] Wheeler, W.M. 1911b: 168 (m.); Menozzi, 1927c: 272 (m.); Wheeler, G.C. & Wheeler, J. 1964b: 455 (l.). Senior synonym of ambigua: Lattke, 2011: 220. [Name misspelled as puncticeps by Emery, 1911d: 100; Wheeler, W.M. & Mann, 1914: 14; see Kempf, 1972a: 130.]
 * ambigua. Leptogenys (Lobopelta) ambigua Santschi, 1931c: 267, figs. 2, 3 (w.) PANAMA. Junior synonym of punctaticeps: Lattke, 2011: 220.

Lattke (2011) - Eyes large, covering more than one-third of lateral cephalic margin; mandible slender, parallel sided in full-face view; metanotal groove well impressed; propodeum unarmed; petiolar node elongate, ending in apical lobe; posterior margin of node sinuous.

Worker
Lattke (2011) - Metrics (n = 7) : HL 1.38 – 1.62; HW 1.01 – 1.11; ML 0.81 – 0.91; EL 0.30 – 0.40; SL 1.62 – 1.85; PW 0.84 – 0.94; WL 2.26 – 2.56; PH 0.74 – 0.91; PL 0.71 – 0.84; DPW 0.47–0.54 mm. CI 0.63–0.77; MI 0.80–0.84; OI 0.29–0.38; SI 1.58–1.67; LPI 1.05–1.13; DPI 0.60– 0.67.

Head elongate in full-face view, posterior border straight to very broadly convex, curving onto straight lateral margin; head wider anterad than posterad; anterior clypeal margin laterally concave, forming rounded convex corner laterad of median lobe, median lobe triangular with rounded apex, 3–5 setae present on apex. Compound eye large and convex, diameter occupies at least one-third of lateral cephalic margin. Scape surpassing posterior cephalic border by almost one-half its length, second antennal segment half as long as third, fourth antennal segment more than half the length of third; all antennal segments longer than broad. Mandibles curved at base, mostly straight in cephalic full-face view; basal and external margins sub-parallel, very gradually widening apicad; mandibular dorsum smooth and shining with sparse punctulae; masticatory margin concave, separated from basal margin by corner. Cephalic dorsum mostly striate-punctate, striae diverging posterad; posterad sculpture becomes smoother, posterolaterally punctate. Head with gap between mandibular dorsal margin and clypeus at least half mandibular width in lateral view. External surface of labium and maxillae mostly smooth, maxilla with median convexity and peripheral sulcus. Cephalic ventrum mostly smooth and shining. Hypostomal tooth brief, not projecting ventrad nor visible in anterior cephalic view.

Mesosoma in lateral view with three dorsal convexities formed by pronotum, mesonotum and propodeal dorsum respectively; propodeal dorsum broadly convex, curving onto straight declivity; promesonotal suture impressed; metanotal groove deeply impressed. Ventral pronotal groove well impressed, propleuron and most of pronotal sides smooth and shining, mesometapleuron and propodeal sides with oblique parallel striae; mesometapleural suture well impressed, forming ridge with mesopleuron elevated above metapleuron. Metapleural-propodeal suture broad and crenulate, becoming weak along anterior one-fourth; metathoracic spiracular prominence rounded and convex; propodeal spiracle oval and facing posterolaterally. Anterior pronotal margin with transverse striae that curve around posterad, sculpture weakening posterad; mesonotum with weak rugulae; propodeal dorsum with weak transverse striae, declivity transversely porcate and flat, rounding onto lateral surface, no teeth or lobes.

Petiole in lateral view subquadrate, with vertical margin one-third to one-half height of posterior margin, curving onto broadly convex dorsal margin, posterior margin sinuate with brief, rounded apical point that barely overhangs concave sector. Laterally mostly smooth ventrad with longitudinal, coarse striae dorsad. Petiole longer than wide in dorsal view, with anterior margin more than half the width of posterior margin; posterior face smooth and shining, slightly sunken. Gaster smooth and shining with sparse punctulae; pygidium mostly straight to very broadly curved in lateral view, without median carina. Body with abundant decumbent hairs; scape with subdecumbent hairs and pubescence; thorax and gaster with none or sparse pubescence. Procoxa in lateral view smooth and shining, no seta on protibial apex. Antennae, mandibles, and legs dark brown; gastral apex ferruginous brown; head, thorax and most of gaster black.

Male
Wheeler (1911) - The male measures 4.5- 5 mm. and in color, sculpture, pilosity and the shape of the petiole is very similar to the worker. The head is as broad as long, nearly circular, with very small, lobe-like, yellbw mandibles and the clypeus broad, convex but ecarinate, and with a broadly rounded, entire anterior border. The wings are rather short, distinctly infuscated, with brown veins and black stigma.

Type Material
Lattke (2011):

Holotype worker: Costa Rica, Jiménez (M.A. Alfaro) [examined].

Leptogenys (Lobopelta) ambigua Santschi, 1931: 267, figs. 2, 3. Syntype workers: Panama, France Field, 20.vi.1930 (A. Bierig) [examined].

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 & Phylogeny, 69, 127-264. PDF]]