Odessa Barb

The Odessa barb is a small fish with a laterally compressed body. Among 28 adult specimens (12 males, 16 females) measured in its species description, both sexes were up to about 4.6 centimetres (1.8 in) SL. Hobby aquarist profiles have noted a length of 7 centimetres (2.8 in) SL. This species exhibits sexual dimorphism, which allows for easy identification of the sexes.

The male has a beige to light brown background color, but is noted for the bright red stripe running the length of the body. The male also has red irises with a narrow black streak through the middle of the eye. The dorsal, anal, and pelvic fins of the male are yellowish green in color, with contrasting black spots. When in spawning condition, the body coloration can intensify with the background becoming darker and the red intensifying on the lateral stripe. The female is plainly colored, with a light beige body and a reflecting silvery sheen on the scales. The fins of the female are a light yellowish green; however, only the dorsal fin contains the contrasting black spots, which are fainter than those of the male. Both sexes have a black and prominent spot in the dorsal area, as well as a smaller spot in the caudal area.

This fish is known by the ornamental fish species name "Odessa barb" because it was said to have first appeared in pet enthusiast's circles in Odesa, Ukraine in the early 1970s. The genus name Pethia refers to a group of small sized barbs present predominantly in South and Southeast Asia. The species name "padamya" is Burmese for ruby, and was chosen in reference to the alternate ornamental fish name "ruby barb" and the vivid color marking of the male.