Cetopsis caiapo Vari, Ferraris & de Pinna, 2005
Identification: Cetopsis caiapo can be distinguished from all of its congeners by the combination of the presence of an eye, the large conical teeth on the vomer and dentary, the rounded posterior nares which is distinctly separated from the contralateral nares by a distance greater than the width of the posterior nares, the dark humeral spot, the absence of a posteriorly-rounded, variably-developed, bilobed patch of dark pigmentation at the base of the caudal fin, the absence of a band of dark pigmentation along the distal portions of the anal fin, and the possession of 44 total vertebrae, 29 caudal vertebrae, 22 total anal-fin rays, and 18 branched anal-fin rays. Maximum size: 69 mm SL.
Range: Cetopsis caiapo is only known from one locality in the Rio Tocantins basin, Brazil.
Information from Vari, R. P., C. J. Ferraris Jr. & M. C. C. de Pinna. 2005. The Neotropical whale catfishes (Siluriformes: Cetopsidae: Cetopsinae), a revisionary study. Neotropical Ichthyology 3:127-238.