Hemibagrus nemerus (Valenciennes,
1839) |
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 catfish, Hemibagrus
wyckioides. 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 con specifics.
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
tank"!.
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.
Hemibagrus nemerus (juvenile) |
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 feeding on 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.
| Etymology |
Hemi-
half; bagrus-
From 'bagre', a South American name
for a catfish, but is only used for African and Asian species.
|
| References |
Froese, R. and D. Pauly.
Editors. 2004. FishBase. World Wide Web electronic publication.
www.fishbase.org, version (11/2004).
Rainboth,
W.J., 1996 Fishes of the Cambodian Mekong. FAO Species
Identification Field Guide for Fishery Purposes. FAO, Rome, 265
p.
Top: &
Middle 
Aqualog Verlag;
from the book Aqualog Photo Collection 1 and is therefore
copyright to this publication.
Bottom:  |
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Cambodia, 
Indonesia, Laos.
Malaysia.
Singapore.
Thailand.
Viet Nam 
