oliveirai (Lundberg & Rapp Py-Daniel,
contributors to this species:
Sabaj Pérez (1)
||The combination of the
absence of a spinelet associated with the dorsal fin, the absence
of spines on the dorsal and pectoral fins, and the possession of
a single row of teeth on the vomer distinguishes Cetopsis
from the other genera in the Cetopsinae. This species can be readily
distinguished from all other members of the Cetopsinae by its complete
absence of eyes (versus the presence of those organs to some degree
in all other species of the Cetopsinae) and the presence of extremely-elongate
distal filaments on the first ray of the dorsal fin (length of fin
longer than one-half of the SL) and pectoral fin (filament extending
posteriorly to beyond the vertical through the middle of the base
of the anal fin). It is further distinguished among the species
of Cetopsis by the number of total anal-fin rays (17 to
19 versus 22 or above in all congeners) and caudal vertebrae (25
or 26 versus 28 or above, respectively). Sexual dimorphism:
Cetopsis oliveirai does not demonstrate the sexual dimorphism
in the degree of development of the dramatically-developed filaments
on the dorsal and pectoral fins and in the form of the margin of
anal-fin that is present in many other species of the Cetopsinae.
America: The middle and upper portions of the Amazon basin
in Brazil and Peru. Type locality: Brazil, Amazonas
State, Rio Solimões north of Ilha da Marchantaria, approximately
15 km upstream of the mouth of Rio Negro at Manaus, approximately
15 m depth, 3º15'S, 60º00'W.
||Vari, R.P., C.J.
Ferraris, Jr. and M.C.C. de Pinna 2005 The neotropical
whale catfishes (Siluriformes: Cetopsidae: Cetopsinae), a revisionary
study. Neotrop. Ichthyol. 3(2):127-238.
Ferraris, C.J. Jr., 2007. Checklist of catfishes,
recent and fossil (Osteichthyes: Siluriformes), and catalogue of
siluriform primary types. Zootaxa 1418:1-628.