end of the year, December 2020 brings us to the Doradidae
family and what aquarists call "Mouse Catfish"
due to there timid and crespecular habits. The species
in question is Tenellus
trimaculatus and is a very popular catfish with
Dorad enthusiasts although along with most members
of this genus are not too common in the hobby.
is a new genus, described by Birindelli (2014) to
include the Nemadoras genera including our
factsheet of the month, Nemadoras
ternetziand the new speciesN.
The snout is constricted, narrowly compressed (gape
very small); dorsal profile concave between tip of
snout and posterior nares.
All of this genera
are found in the Amazon, Orinoco and Essequibo River
basins over sandy bottoms and are found in large shoals
and behave much like Corydoras in their natural
habitats. The large eyes tell us that it is a crepuscular
light species coming out during the evening to look
for food so maybe a good idea to feed towards the
end of the day.
Distrbution:Amazon, Orinoco and Essequibo River
basins. Type Locality:
Rio Jurua an affluant of the Amazons.
The Doradidae family is very
diverse with size being the main criteria with the
smallest species Physopyxis
lyra, growing to 3.5cm. (1½ins)
and, at the other end of the scale we have Oxydoras
niger which grows
to over 90cm (36ins) and is by the way is a gentle
giant. The family is divided into two main groups
with the head shape being the main criteria. One
group can me characterised by the depressed head
which is wider than its height and has unbranched
barbels such as Platydoras
armulatus. The second
group which includes Tenellus trimaculatus
has a longer head and sports branched barbels with
a head that is higher than it is wide.
Amazon, Orinoco and Essequibo River basins. Type
Locality: Rio Jurua an affluant of the Amazons.
Snout constricted, narrowly
compressed (gape very small); dorsal profile concave
between tip of snout and posterior nares with less
than 37 mid-side plates. Large eyes without fat covering
or weakly developed. Nuchal foramina present. Three
pairs of barbels. Fimbriate maxillary barbels; 8 branched
rays on lower lobe of caudal fin.
It has a very pale yellow body,
almost white and with a black spot at the base of
each lobe of the tail fin, and another at the base
of the dorsal fin. The distal upper and lower lobes
of caudal fin are hyaline. In an aquarium environment
the colour of the body is somewhat darkened.
Care & Compatibility
Best kept in groups 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
and a sand substrate as they will dig into the sand
for food particles. Provide a shaded area away from
bright light such as driftwood/rocks and plants.
males will exhibit dorsal fin spines prolonged by
a thin flexible filament nearly as long as the spine
itself, whereas mature females exhibit normal spines
(Sabaj, Mark Henry et al. 2014).
In its natural habitat they
will feed on insects buried in the river bottom so
in the aquarium, Tubifex, Daphnia, and
Cyclops. Once settled in they will take frozen
foods, flake and tablet foods.
Tail Caudal peduncle: The narrow part
of a fish's body to which the caudal or tail fin is
attached. Dorsal fin:The
primary rayed fin(s) on top of the body. Lateral line: A sensory line, along
the sides of the body. Maxillary barbels: Pertaining to
the upper jaw (maxillary barbels). Nuchal:Area between
the skull and dorsal fin. Pectoral: The paired fins just behind
Tenellus:Comes from the Latin
tener, meaning delicate, in reference to the delicate
appearance of those dorads. trimaculatus:
Three spots, one at the base of each lobe of the tail
fin, and another at the base of the dorsal fin.
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]. Conservación
Internacional; seris de Guías Tropicales
De Campo. Pecos del medio Amazonas Región de
Leticia. 546 p. Ferraris, Carl Jr. Dr.
1991. Catfish in the Aquarium. Tetra Press Publication. Sabaj,
M.H. and C.J. Ferraris, Jr.
2003 Doradidae (Thorny catfishes). p. 456-469. In
R.E. Reis, S.O. Kullander and C.J. Ferraris, Jr. (eds.)
Checklist of the Freshwater Fishes of South and Central
America. Porto Alegre: EDIPUCRS, Brasil. ScotCat
Article no. 57Mark H. Sabaj; Key
to Leptodoras and Select Related Taxa.
Sleen, van der Peter and Albert, S. James;
Field guide of the Amazon, Orinoco & Guianas.
Princeton University Press, Princeton and Oxford.