Hemibagrus nemerus (Valenciennes,
e continue our look at another "Wolf
in sheep's clothing" continuing the theme from our 100th
factsheet two months ago in spotlighting the Asian Red Tailed
A close associate this month from the Bagridae family
and from the same genus is Hemibagrus nemerus. If you
look up Fishbase the common name for this species is the Asian
Red Tailed Catfish which is also a widely used name in the hobby
for H.wyckioides but considering that H.nemerus
does not sport a truly red tail, more of a pinkish/orange variety,
I have taken it upon myself to give it the common name of the
False Asian Red Tailed Catfish. Common names don't really matter
in the great theme of things as long as we get the right scientific
name for this species.
This can become a pretty nasty character
in your fish tanks and if housed with other fish can be lethal.
Cichlids such as the Pikes from the Crenichla genus that
can look after themselves would be the best bet for other tankmates.
I have housed them with Synodontis and they can make
a lot of damage to their fins and can kill smaller specimens by
charging them midriff and causing internal injuries.
The reason for this factsheet this month is that there are a lot
for sale around the U.K. at present going under various names
with such as Mystus gulio and there seems to be quite
an influx of asian imports at the present (Nov.2004). They look
quite nice at about 10cm (4inch) and you could be fooled into
thinking that "they would make a nice addition to my community
There are a few identification checks
to make between H.nemerus and H.wyckioides. H.nemerus
has a smaller adipose fin and a identifying black mark on
this fin which can even be seen on the farm bred albino variety
above. It also possess a filament extension to the top caudal
lobe and there are a few specimens that do not even have the pinkish/orange
colour to the caudal but have the same colouration as the body.
Tying in with the factsheet of two months
ago, Hemibagrus wyckioides, there is also a link to last
months factshheet for the Helicopter catfish Wallago
lerii, in that this enormous catfish
from the Siluridae family actually predates on H.nemerus in
its native habitat so there is always something else higher up in
the food chain!.
Your tank set-up should be at least a 4ft long for juveniles with
either gravel or a sand base with rockwork and also plants if you
so prefer. H.nemerus will rearrange the substrate to suit
itself anyway with the gravel bed being shifted and usually banked
up the side of the aquarium walls. External filtration is a better
bet with weekly water changes carried out, although this catfish
is very hardy and can take most tank parameters.
In its native habitat they are caught by seines, hook and line,
gill nets, cast nets and traps and then taken to the local markets
to be sold fresh.
The dorsal fin has 2 spines with 7 soft rays.
The anal fin has 10-13 soft rays.
Base of adipose fin shorter than that of dorsal fin and about equal
to that of anal fin. Barbels four pairs; nasal barbels extending
to or beyond eyes, maxillary ones in anal fin, mandibulary ones
beyond base of pectoral fins, mental ones 2/3 - 3/4 the distance
between their base and insertion of pectoral fins. Head flattened
rather than conical; rugose skull roof; depressed dorsal fin not
reaching adipose fin; pectoral fin smooth in front.
Body colour brown often with greenish sheen.
Fins grey with violet tint. Caudal
fin sometimes shows a pinkish/orange colouration. Dark pigmentation
to adipose fin.
Not to be trusted with other fish. If kept
with other fish they will have to be able to look after themselves
as mentioned above.
There are no known reported aquarium spawning's
of this catfish, most likely due to the eventual size that these
fish attain and their aggressive nature! The males are said to possess
a genital papilla just in front of the anal fin. Breeds
in the summer months in its natural habitat. Moves
into the flooded forest to spawn and the youngsters are usually
seen in August. Returns to the larger
Rivers at the end of the year.
Whilst this catfish is best described as a
predator/carnivore in its natural habitat feedings of fish, insects,
shrimps and other crustaceans, in captivity this catfish will feed
on mussels, prawns, pieces of fish, earthworms and will even take
prepared foods such as catfish pellets.
Froese, R. and D. Pauly.
Editors. 2004. FishBase. World Wide Web electronic publication.
www.fishbase.org, version (11/2004).
half; bagrus- From 'bagre', a South
American name for a catfish, but is only used for African
and Asian species.
Rainboth, W.J., 1996 Fishes of the Cambodian Mekong.
FAO Species Identification Field Guide for Fishery Purposes. FAO,
Rome, 265 p.