Leptogenys sonora

The collecting locality is described by C. Schmidt as Sonoran desert scrub on the periphery of a canyon, with a subtropical Ficus-palm forest along the canyon bottom. The ants were foraging on the ground, on and among rocks and on a large rock face on the canyon side.

Identification
Head with vertexal carinae distinctly visible along most of posterior margin in full-face view; median clypeal lobe bluntly pointed, broadly triangular, lateral margin lamellate; lateral lobe sinuate, anteriorly convex. Compound eye diameter covers approximately one-fourth of lateral cephalic margin, head densely areolate-punctulate. Mandible elongate, subtriangular, gradually widening apicad, basal margin broadly convex, external margin sinuate, masticatory margin broadly concave, dorsum with fine parallel striae. Hypostomal tooth visible between internal mandibular base and clypeus. Tibial apices lacking setae.

A member of the elongata species group.

Distribution
This taxon is known from western Mexico.

Castes
Queen, male. Unknown.

Nomenclature

 *  sonora. Leptogenys sonora Lattke, 2011: 165, fig. 22 (w.) MEXICO.

Worker
Metrics, holotype (paratype): HL 18.50 (18.50); HW 14.00 (14.50); ML 11.50 (12.00); EL 3.00 (3.00); SL 23.50 (23.50); PW 11.00 (11.00); WL 32.00 (32.50); PH 11.50 (11.00); PL 9.50 (10.50); DPW 8.00 (8.00) mm. CI 0.76 (0.78); MI 0.82 (0.83); OI 0.21 (0.21); SI 1.68 (1.62); LPI 1.21 (1.05); DPI 0.84 (0.76).

Head elongate in full-face view, wider anterad than posterad, posterior and lateral margins weakly convex, vertexal carinae distinctly visible along most of posterior margin; median clypeal lobe bluntly pointed, broadly triangular, lateral margin lamellate; lateral lobe sinuate, anteriorly convex, forming obtuse angle with median lobe. Compound eye prominent, semispherical, diameter covers approximately one-fourth of lateral cephalic margin, situated just anterad of cephalic mid-length; circumocular sulcus ample. Head densely areolate-punctulate, clypeus with oblique striae, strongest laterad. Scape surpasses posterior cephalic border by over one-third its length; punctulate with dense decumbent pubescence and scattered decumbent hairs, only slightly longer than pubescence. Funicular segments elongate, subcylindrical, slightly wider apicad than basad; third antennal segment almost 4 x longer than maximum width; third antennal segment approximately 2 x length of second; fourth antenna segment more than half the length of third segment. Mandibles elongate, subtriangular, gradually widening apicad, basal margin broadly convex, external margin sinuate, masticatory margin broadly concave, dorsum with fine parallel striae. Hypostomal tooth visible between internal mandibular base and clypeus.

Mesosoma with deep metanotal groove in lateral view, dividing convex promesonotal margin and broadly convex to medially straight dorsal propodeal margin. Mesonotum convex with dorsal margin not totally continuous with pronotum. Pronotum laterally longitudinally striate-rugulose, narrow smooth area present laterally dorsad of prosternum. Prosternum transversely striate. Mesopleuron-lateral propodeum transversely to obliquely striate, anteroventrally with low blunt denticle, anteroventral carinae lacking, suture weakly developed; mesosternum transversely striate; metapleuron – lateral propodeum longitudinally striate. Dorsum of pronotum with arching striae, posterior disc tending to smooth. Propodeal declivity transversely striate, striae extending dorsad, becoming striate punctate; bulla of metathoracic spiracle convex, prominent, finely sculptured. Mesonotum longer than broad in dorsal view with transverse striae, anterior margin convex, posterior margin with bluntly angular apex pointing anterad. Metanotal groove smooth and shining. Propodeal spiracle elongate.

Petiole subquadrate in lateral view with convex anterodorsal margin, highest point posterad, posterior margin slightly inclined anterad. Node laterally mostly imbricate, tending to smooth ventrad and with transverse striae posterad. Petiolar sternum with ventroposterior swelling. Posterior node face mostly punctulae medially and dorsally, mostly smooth and shining ventrad. Node longer than broad in dorsal view, anterior margin more than half the width of posterior margin, anterior margin convex, posterior margin transverse. Anterior margin of abdominal segment III vertical in lateral view, anterodorsally convex until fourth abdominal tergite. Gaster mostly smooth and shining with fine punctulae that diminish in density posterad. Pygidial margin broadly convex in lateral view, median crest present. Procoxa transversely striate to rugulose in lateral view, rest of legs mostly finely punctate to weakly imbricate. Body with abundant decumbent pilosity, and sparse relatively short erect to semi-erect hairs. Body color mostly ferruginous, with legs slightly lighter colored than rest of body. Tibial apices lacking setae.

Type Material
Holotype worker. Mexico, Sonora, Nacapule Canyon, Sierra Aguajes, nr. San Carlos, 28°0.92′N 111°4.07′W, 78 m, 17.iii.2005, C. Schmidt, M.R. Tarre, CSC590. Deposited in. – Paratype. One worker with same collection data. Deposited in.

Etymology
The species name alludes both to the Sonoran desert, and the State of Sonora, from which the type specimens were obtained.