Bagrid has been a mainstay of the catfish hobby in
the U.K. for many years now and you can still purchase
them under the older genus name of Leiocassis
the name that most aquarists will be more familiar
with, so if you are looking for more info on this
species in books, Leiocassis will do for a
start. Pseudomystus was actually a subgenus
of Leiocassis which K.C. Jayaram had placed
siamensis in, in 1968, but is now a full genus
Below is the comparisons
made by Jayaram taken from "The Atlas of Freshwater
and Marine Catfishes" by Dr. Warren E.Burgess. 1a. Snout angular and produced beyond the inferior
mouth; snout length greater than interorbital width..........Leiocassis. 1b. Snout rounded or obtuse, not produced beyond
the subterminal mouth; snout length equal to or less
than interorbital width..........Pseudomystus.
gets sold as Pseudomystus
known in shops as Leiocassis) in some aquatic
outlets but the colouration is different (stenomus
does not sport banding in the body) and siamensis
grows larger and is more predatory towards smaller
tankmates. It is known under its common name of the
"Asian Bumblebee Catfish", it is nocturnal
and can be territorial with others and its own kind
and will prowl the tank after lights out, so I would
definitely not house them with smaller fish as they
will view them as a snack!. They can also nip the
fins of larger species, so keep well fed with a feeding
after lights out to curb this aggression, but in saying
that they are a favourite fish with myself and other
catfish enthusiasts and it is worthwhile to find a
niche in your (larger) community tank for this species.
It is very hardy in a aquarium setting relating to
water temperature and p.H. having a tolerance to a
wide spectrum of water conditions, but of course not
as extreme as to cause stress.
stamp of Thailand showing this species
found in the rivers and streams
of the Mekong and Chao Phrya basins along with the
rivers that empty into the Gulf of Thailand.
and Chao Phraya River basins and peninsular Thailand.
Type locality: Bangpakong River,
Dorsal spines (total): 1-1;
Dorsal softrays (total): 7-7; Anal soft-rays: 16-17.
short barbels (maxillary barbels not reaching base
of pectoral spine); body depth at dorsal-fin origin
larger than head width; a high, rounded adipose fin.
Irregular vertical bars on
a yellowish to dark grey background (sometime plain
dark body); hyaline caudal fin with or without a
single black blotch on each caudal lobe.
Care & Compatibility
Can be kept in a community
tank but would watch if housing an adult with smaller
Characins or Livebearers as they could be picked of
at night when it starts cruising the tank.
They can also nip the fins of
larger species, so keep well fed with a feeding after
lights out to curb this aggression.
Not reported but
would appear to be a substrate spawner laying its
eggs in tangled roots in the wild, I guess the p.H.would
need to be on the acid side for any success with this
There is a fleshy appendage
in front of the anal fin that would indicate sexual
dimorphism which has been noticed in other Bagrids.
In its native habitat it feeds
on aquatic insect larvae including odonatans. A wide
variety of foods can be given in the aquarium as this
species is not fussy as long as it is fed, preferably
after lights out. If you know where it hides out during
the day you can drop tablet food, frozen food etc.into
its resting place underneath stones/slates or bogwood.
False Mystus. siamensis: From Siam (Thailand).
W.E., 1989 An
Atlas of Freshwater and Marine catfishes: a preliminary
survey of the Siluriformes. T.F.H. Publications, Neptune
City, New Jersey.
Baensch, H.A. and R. Riehl1985
Aquarien atlas. Band 2. Mergus, Verlag für Natur-
und Heimtierkunde GmbH, Melle, Germany. 1216 p. Linder, Shane:Catfish
Mailing List 1998. Rainboth,
W.J. 1996 Fishes of the Cambodian Mekong. FAO
Species Identification Field Guide for Fishery Purposes.
FAO, Rome, 265 p. Froese, R. and D. Pauly.
Editors. 1998. FishBase. World Wide Web electronic publication.