Heteropneustes fossilis (Bloch)
1794
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or our first factsheet of 2004 we spotlight on a species
that could be deemed as one of the most dangerous freshwater
catfish kept by aquarists. So as not to alarm unsuspecting keepers
of this animal, the dangerous bit concerns the poison that can
emanate from a gland on the pectoral fin spine and has been known
to be fatal to some humans. If stung you should immerse the wound
in very hot water so as to dissipate the poison and then get in
touch with your local doctor.
Now that we have scared the living daylights out of you :-)
we shall commence with a few facts on the Asian Stinging Catfish.
This catfish for many years was in its own family, Heteropneustidae,
and it is only very recently that it has been moved into the
Clariidae family (Diogo, R., M. Chardon & P. Vandewalle,
2003) which many in the scientific community thought that is
where it should be. There are differences between the two families
listed below. This does mean now that the family Heteropneustidae
is now invalid and is such retired.
Heteropneustidae: Short dorsal fin, two elongate
pulmary sacs that run backwards from the gill through the muscles
in the back.
Clariidae: Dorsal fin, large with many rays. Possess
a much reduced air-bladder and their gills are stiffened to
prevent their collapse when out of water and in a special part
of the gill chamber are spongy arborecent (tree-like) organs
growing from the upper ends of the gill arches.
Heteropneustes fossilis has the same attributes
as the many Clariid species in that it can leave its chosen
home and cross overland to an other body of standing water.
This is helped by its body mucus which helps it from drying
out
Depending on whose thoughts that you attain to, there
is one other species in this family, Heteropneustes
microps. The reason that I mention this is there is
another theory that microps is a junior synonym of
fossilis and they are one and the same fish. The for
fraternity state that the difference is that H.fossilis
has a separation (notch) between the caudal and anal fin and
that H.microps has these two fins joined together.
The against faction say that the the fusion
of these two fins can be caused by injury and therefore are
one and the same species (Rohan Pethiyagoda and Mohomed M. Bahir
1998).
|
Line drawing of Heteropneustes
fossilis above showing the notch
between the anal and caudal fins.
Image of Heteropneustes microps left
with fusion of the anal and caudal fins. |
All in all, not your usual catfish for the beginning hobbyist
but something unusual for the experienced catfish keepers amongst
us, and also a good challange for a breeding project. Give them
a try.
Body elongate, compressed. Abdomen rounded. Four pairs of barbels,
one pair = maxillary; one pair = nasal; two pair = mandibular.
Rayed fin short with 6-7 rays. Anal fin long with 60-79 rays.
Ventral fins 6 rays. Two elongate pulmary sacs that run backwards
from the gill through the muscles in the back.
Uniform grey-brown to olive-brown. Two narrow, pale to yellowish,
longitudinal bands and numerous black spots on the flanks. Fins
often fawn. Anal fin occasionally with dark marbling. Eye yellow.
Apart from giving it the utmost respect when handling, it does
very well in a larger aquarium, and you can either keep it alone
with other inhabitants that are too big for its mouth ( large
Barbs, Cichlids etc.) or in a group situation if you would like
the challenge of breeding them. A sand substrate is best with
hiding places of rock and cavework and making sure that it has
plenty of swimming space, as they do like to cruise the tank during
the nightime hours. Keep your regular water changes up with good
filtration as they are a greedy species, and can make a mess of
your aquarium if good husbandry is not adhered to.
| Sexing |
The females are stockier looking than the
males.
|
| Breeding |
Has been reportedly bred in the aquarium where they excavate a
nest in the substrate and the parents look after and defend the
eggs. The young when born are guarded throughout their early development
and can be fed Brine shrimp naupli and tablet food.
Will eat almost anything such as tablet and pellet foods. Will
also much appreciate some live foods such as garden worms and
other wormlike food. Frozen bloodworm is another good bet. Experiment
with feeding to find the right balance.
| Etymology |
Heteropneustes;
from the Greek heteros meaning
other; Greek, pneo = to breath (atmospheric
air)
fossilis; Ancient.
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| Factsheet
Request |
Matthew Childers
|
| Reference |
Pethiyagoda, Rohan and
Bahir, M. Mohomed; Heteropneustes
microps, a junior synonym of H. fossilis (Osteichthyes:
Heteropneustidae) 1998. Wildlife
Heritage Trust of Sri Lanka
Jayaram, K.C.
The Freshwater Fishes of India. Zoological Survey Of India,
Calcutta.
Burgess, W.E., 1989. An Atlas
of Freshwater and Marine Catfishes: a preliminary survey
of the Siluriformes. T.F.H. Publications, Neptune City,
New Jersey.
Diogo, R., M. Chardon & P. Vandewalle,
2003. Osteology and myology of the cephalic region and pectoral
girdle of Heteropneustes fossilis (Teleostei: Siluriformes),
with comments on the phylogenetic relationships between
Heteropneustes and the clariid catfishes. Animal
Biology, 53: 379-396.
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| Photo
Credits |
First & second picture: Johnny
Jensen's Photographic Library
Bottom picture: Sridhar Sivasubbu from
image at Fishbase
Line Drawing: ( After Misra, K.S. 1962, text-fig.
104) |
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