Naked sand darter Naked sand darter The naked sand darter ("Ammocrypta beanii") is a freshwater fish of the family Percidae. It is found in the south-eastern United States. The naked sand darter is a small fish ranging in size from 40 to 50 mm long, the maximum being around 64 mm. Being a long thin darter, it is devoid of scales with the exception of a few rows above and below the lateral line and sometimes the caudal peduncle. Slightly transparent in life with a yellow color and iridescent operculum, the naked sand darter blends in with its habitat. It has darker bands
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.