Tenellus is a new
genus, described by Birindelli (2014) to include,
Nemadoras
trimaculatus,N.
leporhinus, N.
ternetziand
the new species N. cristinae all of course
now in the Tenellus genera.The
snout is constricted, narrowly compressed (gape very
small); dorsal profile concave between tip of snout
and posterior nares. Abstract:
Tenellus cristinae is described from the upper
Amazonas/Solimões and Madeira basins in Brazil,
Colombia and Peru, with additional specimens from
the upper Meta (Orinoco basin), Colombia, tentatively
treated as conspecific. Tenellus cristinae
is distinguished from congeners by having 3–9
premaxillary teeth in approximately two rows in juveniles
and adults, outermost teeth weakly spatulate and innermost
more acicular (vs. premaxillary edentulous in adults
of all congeners and limited to 1–6 acicular
teeth in juveniles of N. elongatus, N.
humeralis, T. leporhinus and T.
ternetzi); and mental barbels with extremely
elongate (filiform) papillae, length of longest papillae
about 4–7 times its width at base (vs. papillae
shorter, length of longest <3 times its width at
base). Tennelus cristinae most closely resembles
T. leporhinus, but is further distinguished
from that species by having shaft and primary fimbriae
of maxillary barbel smooth (vs. outer margin of shaft
and margins of primary fimbriae with distinct secondary
fimbriae). Nuptial specimens of T. cristinae
exhibit sexual dimorphism; in males the pungent dorsal
spine is greatly prolonged by a soft, flexible tip
approximately 19.8–23.9% of the total dorsal
spine length (vs. 5.3–9.4% in females). The
sturdy, spatulate teeth in the upper and lower jaws
of T. cristinae are evidently effective tools
for raking caddisfly larvae from their attached substrates,
as gut contents were dominated by cases and larval
remnants of Nectopsyche (Leptoceridae). Aquarium
Care: Best kept in groups in a large aquarium
as they will not do well singularly. Avoid boisterous
or aggressive tankmates as this is a shy species that
will hide out during the day and appear for food at
night under darkness. Provide a dimly lit tank with
floating plants. Diet: Tubifex,
Daphnia, Cyclops. Once settled in they
will take frozen foods, flake and tablet foods. Etymology:
Tenellus comes from the Latin tener, meaning
delicate, in reference to the delicate appearance
of those dorads. cristinae is named after
the main author's wife, Cristina Sabaj Perez. Remarks:
In some online publications the synonym of Nemadoras
cristinae is still being used for this species.
Common
Name:
None
Synonyms:
Nemadoras
cristinae
Family:
Doradidae
Distribution:
South America:
Amazonas/Solimões and Madeira basins in Brazil,
Colombia and Peru.
Size:
12.5cm. (5ins)
Temp:
22-25°C (72-77°F)
p.H.
6.5-7.0.
Reference:
Birindelli, J. L. O.
2014 (16 Sept.) Phylogenetic relationships of the
South American Doradoidea (Ostariophysi: Siluriformes).
Neotropical Ichthyology v. 12 (no. 3): 451-563 [1-102]. Mark H. Sabaj Pérez,
Mariangeles Arce H, Leandro M. Sousa and José
L. O. Birindelli;
Nemadoras cristinae, new species of thorny catfish
(Siluriformes: Doradidae) with redescriptions of its
congeners. Proceedings of the Academy of Natural Sciences
of Philadelphia 163(1):133-178. 2014.
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