ollowing on from our last Ompok factsheet
which was 18 years ago in 2005 and featured the "Butter
again visit the Siluridae family for our September
2023 factsheet featuring Ompok siluroides
from the Mekong and Chao Phraya River drainage's in
Indochina, the Malay Peninsula, and the Barito River
drainage in southern Borneo and Java.
The genus is recognised to be paraphyletic. The species
of Ompok have been grouped into species groups,
such as the Ompok bimaculatus group (O.
malabaricus, O. miostomus, O. siluroides),
the O. eugeneiatus group (O.
pinnatus), the O. hypophthalmus group
(O. hypopthalmus, O.
and the O. leiacanthus group (O.
O. jaynei, O. leiacanthus). On the other hand,
the monophyly of these species groups is not strong
enough to reassign species to other genera. The O.
eugeneiatus group is likely to be more closely
related to Kryptopterus than the other Ompok
This species was
at one time a synonym for O. bimaculatus
but this species has a silver body. There are two
distinct forms of O. siluroides where the
background pattern differs with the species from the
Mekong with a pale brown colouration on one and the
other form which has a mottled body pattern. With
these two colour forms they are found syntopically.
- xanthic specimen
Occurs in streams
and rivers of all sizes with currents ranging from
sluggish to moderate. It is known from river drainage's
in mainland Southeast Asia (Mekong River drainage
southwards to Singapore and eastwards to the Song
Ba drainage in central Vietnam), Sumatra (Deli River
drainage southwards to the Way Seputih drainage),
Java (Ciujung drainage eastwards to the Kali Brantas
drainage) and Borneo (Baram River drainage southwards
to the Barito River drainage). Its Extent of Occurrence
(EOO) is estimated at 3,533,730 km2 based on a minimum
convex polygon calculated using data in Ng and Hadiaty
(2009) and GBIF (2019), (IUCN 2019).
Chao Phraya River drainage basin.
This species is widely distributed in mainland
Southeast Asia, Sumatra, Java, and Borneo.
Although there is no detailed information
on the population size and trend of this species,
it is still abundant throughout its known
distribution and the population trend is thus
suspected to be stable or declining at a rate
that precludes it from a threatened category.
While there may be localised or regional threats,
they are unlikely to affect this species on
a range-wide scale, and it is likely found
within several protected areas. Therefore,
it is assessed as Least Concern (IUCN 2019).
This species is utilised
as a food fish in subsistence and small-scale
commercial fisheries. Juveniles are occasionally
caught for the ornamental fish trade.
Asia:Mekong and Chao Phraya River drainages in
Indochina, the Malay Peninsula, the Barito River drainage
in southern Borneo and Java.
Dorsal soft rays (total):
4; Anal soft rays: 54 - 74. Two pairs of barbels;
maxillary barbels reaching pelvic fins or anal fins;
mandibulary barbels minute, about as long as diameter
of eye. Eyes small, covered by skin. Dorsal and pelvic
fins small; anal fin long; pectoral fins well developed
vomerine teeth in 2 patches.
Brown, usually marmorated
body with conspicuous round black blotch above pectoral
base and a smaller sometimes indistinct spot at
the caudal peduncle.
Care & Compatibility
This is one of the smaller species in this genera
so should be okay for a large aquarium with fish of
the same size or larger. Will still be a predator
of smaller fish in the aquarium. As of most catfish
they will prefer hiding places such as pipes or driftwood.
Males are slimmer
and have serrations on the posterior edge of the pectoral
spine, females lack these serrations.
Moves into freshly inundated habitats during the flood
season and feeds on crustaceans and mollusks. In the
aquarium they will take most aquarium fare such as
tablet, pellet, live and frozen foods.
fin:The median, unpaired,
ventrally located fin that lies behind the anus, usually
on the posterior half of the fish.
Caudal fin:The tail.
Dorsal fin: The primary rayed fin(s) on top
of the body. Mandibular barbels: Pertaining to
the lower jaw. (mandibular barbels). Maxillary
barbels : Pertaining to the upper jaw. (maxillary
The term monophyly, or monophyletic,
derives from the two Ancient Greek words µóvoç
(mónos), meaning "alone, only, unique",
(phûlon), meaning "genus, species",
and refers to the fact that a monophyletic group includes
organisms (e.g., genera, species) consisting of all
the descendants of a unique common ancestor. Paraphyletic:
Of a group of organisms, descended
from a common evolutionary ancestor or ancestral group,
but not including all the descendant groups. Pectoral fins: The paired fins just
behind the head. Pelvic fin:
The paired fins,
between the pectorals and the anal fins. (also referred
to as ventrals). Syntopically:
Referring to a type of analysis
in which different works are compared and contrasted.
and sharp, more or less protruding according to the
species, the vomerine crest (Crista vomeris) is the
caudal, or guttural part of the ventral part of the
vomer bone. Xanthic:
Relating to, or tending towards a yellow colour.
It has been suggested that the name is a bad reproduction
of the Malay name 'limpok'. Or from the vernucular
siluroides: –oides, having the
form of: Silurus, a related genus from Europe, but
in this case perhaps referring to catfishes in general.
Froese, R. and D.
Pauly. Editors. 2014. FishBase.World Wide
Web electronic publication. www.fishbase.org, (
11/2014 ). Kottelat, M., 2001. Fishes of Laos.
WHT Publications Ltd., Colombo 5, Sri Lanka. 198
p. Nagao Natural Environment Foundation.
Tokyo. Fishes of the Indochinese Mekong. 545.p. Ng, H.H. 2019. Ompok siluroides.
The IUCN Red List of Threatened Species 2019. Ng, H.H. and R.K. Hadiaty, 2009.
Ompok brevirictus, a new catfish (Teleostei: Siluridae)
from Sumatra. Zootaxa 2232:50-60. Rainboth, W.J.,
1996. Fishes of the Cambodian Mekong. FAO Species
Identification Field Guide for Fishery Purposes.
FAO, Rome, 265 p.