Harlequin Rasboras have very distinctive markings that make them easily identifiable from other Rasbora species. Harlequin Rasboras have a round shape to their bodies with short fins. They have a silvery sheen to their bodies that seem to have an orangish shine emanating from its core. Harlequin Rasbora male and females have a black triangle shape that extends vertically from their dorsal fin to their caudal fin. The tip of the black triangle ends at the tail of the Harlequin Rasbora.