Hassar orestis (Steindachner,
ur first factsheet of 2018 takes us to a family of catfishes that
are loved by most cat enthusiasts, namely the Doradidae and this
month the "Black
Top Mouse Catfish",
Hasser orestis has our focus. In
days gone by this was in most literature, and can still be found
today, under the synonym Hassar notospilus (Eigenmann,
H. orestis is
similar looking to Nemadoras
leporhinus but this species has
longer leading fin rays and sports a clear dorsal with black
markings at the base. The genes Hassar also differs
from its close relative Opsodoras in having an
elongate eye (Opsodoras round eye) and long snout
(snout shorter with a more rounded profile in Opsodoras)
= showing the
long snout and the elongate eye
For a large species it is non aggressive
and can be kept with smaller species such as small characins,
dwarf cichlids, small labyrinth species and also other small catfish
such as Corydoras and the smaller members of the Loracariids.
Provide a soft substrate such as fine sand as they like to sift
through this for edibles and a sharp substrate could cause damage
to its fine feathered barbels.
Head narrow with long snout. Maxillary
barbels reaching pectoral, with small barblets. Mental barbels
papillose. Lateral plates small, the largest approximately 1.33
times the size of the eye. Large foramen present on occipital
Body light grey, underside white. Minute black
spotting around base of dorsal. Conspicuous black blotch in dorsal.
This is a particularly
delicate aquarium fish with low tolerence to adverse water
conditions and disease. Lone individuals will not do well
in an aquarium setup so a group of three or more will be
more beneficial to the long term health of this species.
A planted aquarium is a must as they like to hide in the
roots more so than having a rock or wood setup.
Can be kept with smaller species such
as small characins, dwarf cichlids, small labyrinth species and
also other small catfish such as Corydoras and the smaller
members of the Loracariids.
Males possess an elongated
first dorsal ray. Females have more rounded pectoral fins
Tablet foods, small live and frozen foods
such as worms and Daphnia.
Pertaining to the upper jaw. (maxillary barbels)
Mental barbels: Pertaining to the chin,
on the lower jaw. (mental barbels)
Papillose: A small fleshy projection, plural papillae.
Lateral: A sensory line, along the sides
of the body.
Foramen: magnum (Latin: great hole) is
a large oval opening (foramen) in the occipital bone of
the skull in humans and various other animals. It is one
of the several oval or circular openings (foramina) in the
base of the skull.
median bone on the upper surface of the back of the head;
pertaining to the occiput.
Dorsal: The primary rayed fin(s) on top
of the body.
From the Aruac name of the fish.
orestis: A mountaineer.
Baensch, H.A. and R. Riehl 1985
Aquarien atlas. Band 2. Mergus, Verlag für Natur- und Heimtierkunde
GmbH, Melle, Germany. 1216 p
Catfish Association of Great Britain: Information
Book 6, 1980. 18p.