Key to species of subgenus Carinichelonus Tobias, 2000

1 Antenna of female filiform and not widened after middle, 3 rd antennomere short, its length 2.5 × its width (Fig. 2H); pterostigma 1.2–1.3 × longer than vein 1-R1 of fore wing (Fig. 2A); metasoma of male entirely black (Figs 2D, E)...................................................................................... C. (C.) tabonus Sonan, 1932 comb. nov.

- Antenna of female clearly widened after middle, 3 rd antennomere its length 4.3 × its width; pterostigma as long as vein 1-R1 of fore wing; metasoma of male with pair of small yellowish latero-basal spots and with pair of brownish yellow circular spot above apex of ventral opening.................................... C. (C.) siangensis Ranjith & Priyadarsanan, 2023