Pethia striata can be diagnosed from other species of the genus Pethia by the combination of the following characters: lateral line complete, with 20-21 pored scales up to tail fin base; upper half of body dark brown; outer edges of body scales dark, forming oblique bars, giving a distinct striped pattern along the side in both sexes; dorsal fin dark with a pale outer margin; dorsal, pectoral, pelvic, and anal fins tinged with black; caudal fin hyaline; black humeral spot one scale below the 4th lateral-line scales, a larger black blotch 3-4 scales high covering the 17th to 19th lateral-line scales, and only 2 scales between this blotch and the hypural notch. Other characters useful to distinguish from other congeners include the following: fewer transverse scales, 3 scales between lateral-line scale row and ventral fin; ½ 4+1+3 transverse scales; eight predorsal scales; a smaller humeral spot, restricted to a single scale; lacking a gray patch below the dorsal fin; two spots, a humeral spot and a caudal-peduncle blotch; 2+3-4 gill rakers on the first gill arch; a single blotch on the caudal peduncle; dark longitudinal band absent; and dorsal fin of

male is black (Ref. 104010).