Brachyponera, EMERY, 1900

Key to the Thai species of Brachyponera View in CoL based on worker caste

1. Eye very small, present as a dot, with 2–3 ommatidia along longest axis ( Fig. 3B View Fig 3 ) …… …………………………………………..……………….…….…….… B. kumtongi sp. n.

– Eye medium to large sizes, with over 6 ommatidia along longest axis ( Figs. 3C–F View Fig 3 ) …..... 2

2. Eye with 7–8 ommatidia along longest axis; antennal scape short, when folded back in full-face view reach or just slightly extending beyond posterior margin of head (SI 93– 100) …………………………………………………………..…….……..…..…………. 3

– Eye with 10–12 ommatidia along longest axis ( Figs. 3E View Fig 3 and 4F View Fig 4 ); antennal scape long, when folded back in full-face view distinctly extending beyond posterior margin of head (SI 100–136) ……………………………………………………………….......….………... 4

3. Head in full-face view with dense fine micropunctures ( Fig. 3G View Fig 3 ); body yellowish brown to reddish brown ( Fig. 2A View Fig 2 ); posterior margin of head almost straight ( Fig. 3G View Fig 3 ). ………… ...…………………………………………………………….…….. B. troglomorpha sp. n.

– Head in full-face view with dense irregular striations (fig. 3H); body black to dark brown; ( Fig. 3I View Fig 3 ); posterior margin of head concave ( Fig. 3H View Fig 3 ) ………..... B. luteipes (Mayr, 1862) View in CoL

4. First gastral tergite with over 10 erect hairs ( Fig. 3J View Fig 3 ); smaller species (HW 0.72–0.83 mm) ………………….………………….………………………… B. chinensis (Emery, 1895) View in CoL

– First gastral tergite with 3–4 erect hairs ( Fig. 3K View Fig 3 ); larger species (HW 0.95–1.06 mm).… ………………..…………………………………….……..……. B. nigrita (Emery, 1895) View in CoL