Petrocephalus longianalisPetrocephalus longianalis is a species of electric fish in the family Mormyridae. It is found in the lower and upper Luapula River system in Zambia.SizeThis species reaches a length of.EtymologyThe fish's name means longus, "long"; analis, "anal", referring to higher number of anal-fin rays compared with congeners covered in the authors' study.