Redtail Catfish, Phractocephalus hemioliopterus
The Redtail Catfish (Phractocephalus hemioliopterus) is a species of long-whiskered catfish found in South America. It is native to the Amazon, Orinoco, and Essequibo river basins of South America. It is found only in fresh water. It has been introduced into Florida, although it has not been established there. It is commonly known as cajaro in Venezuela and pirarara in Brazil. It is the only still-living member of the genus Phractocephalus. Despite growing to a large size, it is a popular aquarium fish.
The Redtail has a broad head with a wide mouth. The body is mainly dark gray with small darker gray spots. The ventral surface is paler. The Redtail has three pairs of long barbels. A lateral white band starts at the caudal peduncle and runs anteriorly, tapering to end anywhere from midway along the body to just behind the operculum. The caudal fin is red or orange, giving the fish its common name. The juveniles may be more intensely colored. An adult Redtail can reach a length of 4 feet and weigh over 97 pounds. Because of its large size, it is a popular game fish. The largest specimen ever recorded weighed 113.5 pounds.
In captivity when well-fed, the Redtail can grow rapidly. It should be fed weekly, but overfeeding can cause death. It relies heavily on live and dead fishes and other meat. Even young fish can consume many of the more common aquarium fish species and as such, all redtail catfish should be kept in tanks with other similar large size species. The Redtail Catfish has also been known to swallow inedible objects in the aquarium, though these objects are usually regurgitated. This can pose a problem however, and objects are best kept out of aquariums with Redtail Catfish.
Image Caption: Adult Redtail in an aquarium. Credit: Monika Betley/Wikipedia (CC BY-SA 3.0)