Phalloceros anisophallosPhalloceros anisophallos, the Roque toothcarp, is a species of poeciliid fish native to Brazil.DistributionPhalloceros anisophallos is found in Brazil in the drainages of rio Parati, rio Barra Grande, rio São Roque, rio Taquari and rio Itinguçu which are small coastal drainages of Rio de Janeiro.SizeThe females of this species grow to a total length of, while males remain smaller at.HabitatThe fish live in tropical freshwater; and are benthopelagic.EtymologyThe fish is named in Latin anisos, of unequal or of uneven; phallos, meaning penis, and referring to the asymmetrical terminal appendix of the gonopodium.