Leptogenys yandii

The types were collected from valley rainforest nesting inside decayed wood, foraging on the ground, and nesting in the soil.

Identification
Xu and He (2015) - Similar to Leptogenys punctiventris, but its eyes are smaller and occupy one fourth of the lateral cephalic margin; the antennae are shorter, only one fourth length of scape surpasses the posterior head corner, segments 3 and 4 about equal; anterior margin of petiolar node is straight and vertical, anterodorsal corner is narrowly rounded; head dorsum is largely densely punctate, mesosoma, petiolar node and first gastral segment are fully largely punctate, second gastral segment is finely punctate. In L. punctiventris the eyes are larger and occupy one third of the lateral cephalic margin; the antennae are longer, one third of scape length surpasses the posterior head corner, segment 3 longer than segment 4; anterior margin of petiolar node is weakly convex, anterodorsal corner is broadly rounded; head dorsum is finely densely punctate, sides of mesosoma and petiolar node are longitudinally rugose, sides of first gastral segment are mostly smooth and shiny, second gastral segment is smooth and shiny.

Distribution based on Regional Taxon Lists
Palaearctic Region: China.

Nomenclature

 *  yandii. Leptogenys yandii Xu & He, 2015: 145, figs. 28-35 (w.) CHINA.

Worker
Holotype. TL 5.4, HL 1.07, HW 0.73, CI 69, SL 1.07, SI 145, ML 0.53, ED 0.23, PW 0.70, MSL 1.67, PL 0.67, PH 0.70, DPW 0.50, LPI 105, DPI 75.

In full-face view head longer than broad, roughly trapezoidal and widened anteriorly, posterior margin straight and carinate, posterior corner narrowly rounded, lateral margin weakly convex. Mandible narrow and slender, masticatory margin edentate, basal corner bluntly angled. Clypeus acutely longitudinally carinate, weakly convex at apex, each side with blunt tooth. Antenna 12-segmented, scape surpassing posterior head corner by one fourth of its length, flagellar segments longer than broad, segments 3 and 4 about equal. Eye occupying one fourth of lateral cephalic margin, and located in front of midpoint of lateral margin.

In lateral view pronotum weakly convex. Promesonotal suture impressed. Dorsum of mesonotum and propodeum almost straight and slightly lower than pronotum, metanotal groove not impressed. Dorsum of propodeum about 1.5 times as long as declivity, posterodorsal corner blunt. Petiolar node trapezoidal, about 1.1 times higher than long, both anterior and posterior margins straight and vertical, dorsal margin weakly convex, anterodorsal corner narrowly rounded, posterodorsal corner blunt. Subpetiolar process short and slender, roughly triangular, posteroventrally pointed. Constriction between abdominal segments III and IV distinct. Sting extruding.

In dorsal view lateral margin of pronotum strongly convex, posterior margin concave. The rest of mesosoma weakly widened posteriorly. Metanotal groove narrow and visible. Petiolar node trapezoidal, weakly widened posteriorly, about 1.1 times as long as broad, anterior and lateral margins slightly convex, posterior margin straight, anterior corners rounded, posterior corners blunt.

Mandible finely longitudinally striate. Clypeus longitudinally rugose. Head dorsum largely densely punctate with interspace coarsely retirugose. Mesosoma, petiolar node and first gastral segment fully, largely and deeply punctate, interface smooth and shiny, as broad as or narrower than puncture diameter. Mesopleuron and metapleuron densely punctate with interspace coarsely retirugose. Declivity coarsely transversely striate. Second gastral segment finely sparsely punctate, the rest of gaster smooth and shiny. Head dorsum with abundant suberect hairs and subdecumbent pubescence. Dorsa of mesosoma, petiolar node and gaster with sparse suberect hairs and decumbent pubescence. Scape and tibia with sparse subdecumbent hairs and dense decumbent pubescence. Body color black. Mandible, clypeus, antenna, leg and gastral apex reddish brown. Eye grey.

Paratype. TL 5.2 - 5.7, HL 1.07 - 1.10, HW 0.73 - 0.77, CI 67 - 72, SL 1.03 - 1.10, SI 139 - 145, ML 0.50 - 0.57, ED 0.20 - 0.23, PW 0.67 - 0.73, MSL 1.60 - 1.80, PL 0.63 - 0.67, PH 0.70 - 0.73, DPW 0.47 - 0.53, LPI 105 - 119, DPI 70 - 84 (17 individuals measured). With similar morphological characters as holotype, but in some individuals, apex of clypeus roundly convex, punctures on mesopleuron, metapleuron and side of propodeum are relatively larger with interspace reticulate.

Type Material
Holotype worker: China, Tibet, Medog County, Medog Town, Yarang Village, 29°17.760' N, 95°16.599' E, 760 m, nest inside decayed wood in the valley rainforest, 21.V.2008, Zheng-Hui Xu leg., No. A08-1011. Paratypes: 6 workers, with same data as holotype; 1 worker, China: Tibet, Medog County, Beibeng Town, Beibeng Village, 29° 14.593' N, 95° 10.197' E, 730 m, foraging on the ground in the valley rainforest, 23.V.2008, Zheng-Hui Xu leg., No. A08-1113; 7 workers, China: Tibet, Medog County, Damu Town, Damu Village, 29° 29.298' N, 95° 26.659' E, 1200 m, nest in soil in the valley rainforest, 20. VII.2011, Xia Liu leg., No. A11-3852; 3 workers, with same data as No. A11-3852, but foraging on the ground, Nos. A11-3880 (1 worker) and A11-3896 (2 workers).

The type specimens are deposited in the Insect Collection, Southwest Forestry University, Kunming, Yunnan Province, China. Two paratypes are deposited in the Insect Collection, Guangxi Normal University, Guilin, China.

Etymology
The specific epithet refers to “Yandi (Yan Emperor, born about 6000 - 5500 years ago),” one of the two earliest Chinese emperors.

References based on Global Ant Biodiversity Informatics

 * Xu Z. H., and Q. J. He. 2015. Taxonomic review of the ponerine ant genus Leptogenys ROGER, 1861 (Hymenoptera: Formicidae) with a key to the Oriental species. Myrmecological News 21: 137-161.