Ranchu tail. The caudal peduncle itself should be broad and neither lengthy or too short (a properly formed caudal peduncle avoids swimming motion impairments to this type of goldfish). The ranchu's tail meets the caudal peduncle at a forty-five degree angle, giving the fish a unique swimming motion. Furthermore, the tail lobes are rounded, and all other finnage are paired. The most prominent feature of the ranchu is its head. There must be sufficient space between the eyes, and also from the eyes to the front of the head. The gill cover should figuratively extend quite far towards the tail. The
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.