Description
The black ruby barb (Pethia nigrofasciata) or purplehead barb is a tropical fish endemic to Sri Lanka, where it occurs in forested streams. The young fish has a yellowish gray body with black vertical stripes. The silver body turns into a dark ruby red color in mature, breeding males. In the female, the basal part of all the vertical fins are black. In the male, the whole dorsal fin is a deep black, the anal fin blackish red, and the pelvic fins are reddish. The fish will grow to a maximum length of 2–3 inches with the female being slightly longer than the male.