Description:
Cetopsis motatanensis can be distinguished from
all of its congeners by the combination of the presence
of an eye, the conical teeth on the vomer and dentary,
the rounded posterior nares that is distinctly separated
from the contralateral nares by a distance greater
than the width of the posterior nares, the absence
of a 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 dark
pigmentation on the distal portions of the pelvic
and anal fins, the caudal fin darkly pigmented throughout
other than for the narrow pale distal margin, and
the possession of 18 to 20 preanal vertebrae, 15 to
17 precaudal vertebrae, 33 to 35 caudal vertebrae,
48 to 50 total vertebrae, and 9 pectoral-fin rays.
Diet: the Cetopsinae, are
notorious for their voracious feeding habits; attacking
not only carrion, but also live fishes in gill-nets
(Barthem & Goulding, 1997: 44), and on occasion
humans (Goulding, 1989: 185). The predatory and scavenging
feeding habits of these species of Cetopsis
perhaps contributed to the erroneous assumption that
members of the Cetopsinae are “parasitic”;
a conclusion that may have lead various previous researchers
to align members of that subfamily with the species
of the family Trichomycteridae, some members of which
feed on the blood of their hosts. In
contrast to the voracious feeding habits of Cetopsis
candiru and
C.
coecutiens, all other members of the
subfamily for which the diet is known prey primarily
on allochthonous and aquatic insects.
Common
Name:
None
Synonyms:
Pseudocetopsis plumbeus
motatanensis
Family:
Cetopsidae
Distribution:
South America:
Lake Maracaibo basin of Venezuela and Colombia. Type
locality: Río Motatán, 4 km.
above Motatán, Venezuela.
Size:
15.5cm. (6¼ins)
Temp:
22-28°c (71-83°f )
p.H.
6.0-7.0.
Reference:
Ferraris, C.J. Jr.,
2007. Checklist of catfishes, recent and fossil (Osteichthyes:
Siluriformes), and catalogue of siluriform primary
types. Zootaxa 1418:1-628. 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. www.flmnh.ufl.edu
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