Erythrinus erythrinus

Erythrinus erythrinus, the red wolf fish, is a relatively small species of trahira (family Erythrinidae) from freshwater habitats in South America.^[2]

Erythrinus erythrinus
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Characiformes
Family:	Erythrinidae
Genus:	Erythrinus
Species:	E. erythrinus
Binomial name
Erythrinus erythrinus (Bloch & Schneider, 1801)
Synonyms [1]
Synodus erythrinus Bloch & Schneider, 1801 Erythrinus brevicauda Günther, 1864 Erythrinus longipinnis Günther, 1864 Erythrinus salmoneus Gray, 1854

Range and habitat

E. erythrinus is a South American freshwater fish that is native to the Amazon and Orinoco basins, as well as rivers in the Guianas.^[2] The species is also reported as native to the Paraná—Paraguay basin, including the Pantanal,^[3][4] but the population in the lower Paraná basin and Iguazu basin may be an undescribed species.^[5] E. erythrinus has been introduced to the upper Paraná basin where not native.^[6] It mainly lives in creeks and marshes where the water has a pH of 5.6–7.8.^[2]

Appearance and behavior

E. erythrinus can reach a maximum standard length of 20 cm (7.9 in), although other reports suggest it can reach about 25 cm (10 in).^[2]

It feeds primarily on small fish, insects, and benthic crustaceans.^[7] Juveniles are aggressive mimics of female aplocheilid killifish, notably Laimosemion agilae, and they use this to catch male killifish that seek a mate.^[8]

E. erythrinus is not of major interest to fisheries, but is sometimes used as a bait fish^[5] and seen in the aquarium fish trade.^[2]

Taxonomy

It was described by Marcus Elieser Bloch and Johann Gottlob Schneider in 1801,^[9] originally under the lizardfish genus Synodus. The species was first placed in Erythrinus in 1854 by Gray (under the name Erythrinus salmoneus, a junior synonym of Erythrinus erythrinus), and this treatment has been recognized by recent authorities such as Osvaldo Takeshi Oyakawa in 2003.^[10]