Harlequin rasbora of a harlequin. The harlequin rasbora is a fish that has an approximately lozenge-shaped body, whose basal colour from the head to the caudal peduncle is an orange-pink, the exact hue varying depending upon such factors as water conditions and the original population from which the fish was obtained. The posterior half of the body is overlaid with a large, roughly triangular black marking, that tapers toward the terminal end of the caudal peduncle, and begins approximately below the midpoint of the attachment of the dorsal fin (commonly called a "black wedge"). In common with all cyprinids, the articulation of
Apistogramma eremnopyge Apistogramma eremnopyge Apistogramma eremnopyge is a species of cichlid. It is only known from the Rio Pintuyacu, a tributary of the Rio Itaya near Iquitos, Peru. Most of the tributaries of this river system carry acid blackwater (pH ~ 5). This is a small cichlid, standard length which can be easily distinguished from its congeners by the presence of a prominent dark blotch on the lower part of the caudal peduncle in both sexes. The male is strikingly coloured with vivid blue and red patterning on the cheek and operculum and maroon, orange and blue colouring on the dorsal fin.