Dorsal soft rays (total): 10
5.6 cm SL (male/unsexed; (Ref. 86734))
Very similar to Diapoma speculiferum, both species sharing the posterior elongation of opercle and subopercle. Differs from this species in having red fins in live males (vs. pale to yellowish fins in live males), longer snout, 21.3-24.5% of head length (vs. 17-21.4% in head length), and pentacuspid maxillary teeth (vs. tricuspid) (Ref. 86734).Description: Dorsal fin ii, 8; anal-fin rays iv- v, 24-30; pectoral-fin rays i, 9-11; pelvic-fin rays i, 6. Lateral line incomplete, with 10-22 perforated scales on anterior segment, followed by 1-20 non-perforated scales and a posterior segment with 6-26 perforated scales in most specimens. Horizontal scale rows from dorsal-fin origin to anal-fin origin 9-11. Total gill rakers on first gill arch 12-14 (Ref. 86734).