Keys to Oriental Region Leptogenys chinensis group species

Based on Wachkoo et al. (2018) and modified from Xu & He (2015)

Leptogenys chinensis forms a species group with closely related species having little morphological changes Wilson (1958), Sarnat and Economo (2012). From the Oriental region, there are currently 9 species belonging to the L. chinensis group. The group is diagnosed by having edentate masticatory margin of the mandible, smooth body surface, elongate antennae and metallic green cuticle.


 * Leptogenys
 * Ants of China

1

 * Petiolar node strongly elongate in lateral view, about 1.5 times as long as high. . . . . . 2


 * Petiolar node moderately to weakly elongate in lateral view, less than 1.2 times as long as high. . . . . . 3

2
return to couplet #1
 * Antennal scape relatively shorter, surpassing posterior head corner by about two fifths of its length. Petiolar node elongate trapezoidal in lateral view, with very short but distinct anterior margin. Body colour reddish-brown. Relatively smaller species with total length 6.5-7.0 mm . . . . . Leptogenys assamensis


 * Antennal scape very long, surpassing posterior head corner by half of its length. Petiolar node triangular in lateral view, without anterior margin. Body colour black. Large species with total length 13.0-13.5 mm. . . . . . Leptogenys pangui

3
return to couplet #1
 * Petiolar node moderately elongate, as long as high or distinctly longer than high in lateral view. . . . . . 4


 * Petiolar node weakly elongate, distinctly higher than long in lateral view, about 1.3-1.4 times as high as long. . . . . . 8

4
return to couplet #3
 * Clypeus truncated at apex. Larger species with total length 8-11 mm. . . . . . 5


 * Clypeus convex at apex. Smaller species with total length 4.5-7.0 mm. . . . . . 7

5
return to couplet #4
 * Anterior clypeal margin distinctly laterally sinusoid; propodeal declivity transversely striate. . . . . . Leptogenys chinensis


 * Anterolateral clypeal margin, smooth; propodeal declivity smooth and shiny, without transverse striations. . . . . . 6

6
return to couplet #5
 * Gena smooth and shiny, without longitudinal rugae and third antennal segment slightly more than 2× the length of second segment . . . . . Leptogenys bhartii


 * Gena longitudinally rugulose and opaque and third antennal segment distinctly less than 2× the length of second segment. . . . . . Leptogenys kraepelini

7
return to couplet #4
 * Petiolar node distinctly longer than high in lateral view. Sides of mesothorax, metathorax and propodeum mostly smooth and shiny. Body colour black. Relatively larger species with total length 5.9-6.3 mm. . . . . . Leptogenys peuqueti


 * Petiolar node as high as long in lateral view. Sides of mesothorax, metathorax and propodeum mostly irregularly rugose and opaque. Body colour black, gaster blackish-brown. Relatively smaller species with total length 4.5 mm. . . . . . Leptogenys confucii

8
return to couplet #3
 * Clypeus truncated at apex. Eyes relatively smaller and occupying one fourth of head side. Petiolar node relatively longer in lateral view, about 1.3 times as high as long, dorsal margin distinctly longer than anterior margin, anterodorsal corner a rounded obtuse angle, the node obviously longer than broad in dorsal view. . . . . . Leptogenys laeviterga


 * Clypeus pointed and strongly convex at apex. Eyes larger and occupying one third of head side. Petiolar node relatively higher in lateral view, about 1.4 times as high as long, dorsal margin as long as anterior margin, anterodorsal corner a rounded right angle, the node as broad as long in dorsal view. . . . . . Leptogenys sunzii