Vertebrae: 27 - 29. Mature males have more intense coloration, but when disturbed they become similar to the females. Both have opercle with blue to green iridescent scales depending on angle of reflected light. Anal and caudal fins (and sometimes the dorsal fin) are bordered distally by a dark blue edge, followed by an iridescent blue to green border when live; only a blackish distal border is visible when preserved. Differs from other members of the Betta picta species group by the following combination of characters: anal-fin rays 23-26 (mode 26); subdorsal scales 5-6 (mode); lateral scales 27 1/2-30 (mode); caudal peduncle depth 14.8-19.7% SL; head length 30.3-34.5% SL; body depth at dorsal-fin origin 25.3-30.1% SL; length of anal-fin base 47.9-52.7% SL; interorbital width 29.2-36.2% HL (Ref. 56613).