actsheet
no 239, May 2016 has us revisiting the Bagridae famaily
of Asia and a much misidentified species in Mystus
mysticetus.
Mystus
mysticetus
The misidentified
remark is based on other midstriped Mystus species
such as M.
vittatus, M.
tengara, M.
carcio and M.
atrifasciatus.
M. atrifasciatus differs due to it having
less dark lines on the body and having a thinner,
non indented fontanel and having a longer adipose
fin. M. vittatus differs due to M. mysticetus’s
large laterally placed eyes (this trait also includes
M. atrifasciatus). Another similar species
is M.
multiradiatus
which has a longer adipose fin and also the smaller
eye.See images below.
Mystus
multiradiatus
Mystus
atrifasciatus
Mystus mysticetus
is often found in mixed schools
with M. multiradiatus (above) which congregate
around tree limbs and other solid objects, browsing
the hard surfaces for zooplankton, aquatic insects,
crustaceans and rotifers. They move into flooded forests
during the rainy season and return to the rivers in
November and December in the lower Mekong. Oviparous,
distinct pairing possibly like other members of the
same family.
Common
Name
None
Synonyms
Mystus
vittatus(non
Bloch)
Family
Bagridae
Subfamily
-
Distribution
Asia:
Mekong
and Chao Phraya River basins.
Size
13.0cm (5¼ins)
Temp.
22-28°C
(71-83°F)
p.H.
6.0-7.5
Characteristics
Anal soft rays: 13 - 15; Vertebrae:
34 - 37. Differs from all other species of Mystus
in having eyes lateral, rather than dorsolateral,
so that they are about equally visible viewed either
from above or from below head (in other species eyes
usually cannot be seen at all from directly below).
Mouth nearly terminal, less down turned than in any
other species of striped Mystus. Serrae of
pectoral spine smaller and less erect than in any
other striped Mystus. Adipose fin short but
very high, originating far behind dorsal fin, its
length about twice and its height slightly less than
eye diameter. Gill rakers increase in number throughout
life faster than in any other Mystus. The
anal fin has slightly more rays (13-15) than other
striped Mystus of Thailand (usually 12 or
less), and its posterior border is distinctly falcate.
Cranial fontanel extends posteriorly to about midway
between level of posterior border of eye and base
of supraoccipital process. Maxillary barbel extends
posteriorly to beyond anal fin or to end of middle
caudal fin rays.
Colouration
Side of body with 3 faint
dark and 2 whitish stripes. Tips of anal and caudal
fin are often black.
Aquarium
Care & Compatibility
Apart from the confusion on
this Bagrid...how do we keep it in the aquarium?.
Not a problem as long as you keep four or more as
they will do better in a group. This is a medium to
small Bagrid but never the less it is better to keep
species with them that are around about the same size,
as after all they are from the Bagridae family and
most (but not all) can be predatory. Furnish the aquarium
with driftwood for hiding places and plants. Substrate
is a personal choice. Will do well in your medium
to large aquarium with larger Tetra type fish and
Barbs.
Reproduction
Not reported but
oviparous, distinct pairing possibly like other members
of the same family. This
genus is known to be egg scatterers and
may eat the eggs if they are not separated. Cold water
changes may start a pair off if they are kept in a species
tank on their own. There
have been a couple of instances of successfull breeding
attempts with Mystus species, notably M.
armatus and M.
vittatus.
Sexual
Differences
Males have an elongate genital
papilla in front of the anal fin. Females will be fuller
bodied.
Diet
Flake food which will give
them all the vitamins they desire. They should of
course be fed a varied diet consisting of the former,
tablet, pellet foods and frozen foods such as bloodworm.
Glossary
of Terms
Adipose
fin: Fleshy finlike
projection without rays, behind the rayed dorsal fin. Anal fin: The median, unpaired, ventrally
located fin that lies behind the anus, usually on the
posterior half of the fish. Caudal fin: The tail. Falcate: When the anterior fin rays
are prolonged. Fontanel: The
space(s) between the bones on top of the skull covered
by skin. Gill rakers: Structure on the upper
portion of the gill arches. Maxillary: Pertaining to the upper
jaw. (maxillary barbels). Pectoral fin:
The paired fins just behind the head. Supraoccipital: Unpaired bone at the
back of the skull, usually with a crest.
Etymology
Mystus:from “mystax” meaning whiskered
or moustache (hair on the upper lip). Mystus was first
used by Belon in 1553 to describe all fish with whiskers. mysticetus: generic name
of baleen whales, referring to numerous slender, baleen-like
gill rakers.
References
Froese,
R. and D. Pauly. Editors. 2004. FishBase. World
Wide Web electronic publication. www.fishbase.org, version
(10/2004). Rainboth, W.J. 1996 Fishes of the Cambodian
Mekong. FAO Species Identification Field Guide for Fishery
Purposes. FAO, Rome, 265 p. Roberts, T.R.,
1992. Revision of the striped catfishes of Thailand
misidentified as Mystus vittatus, with descriptions
of two new species (Pisces: Bagridae). Ichthyol. Explor.
Freshwat. 3(1):77-88. Serov, D.V., Nezdoliy
V.K., Pavlov, D.S.; The Freshwater Fishes of
Central Vietnam. Scientific Press Ltd. 363 p. ScotCat Article:
Grant, Steven;The
striped catfishes of the genus Mystus Scopoli,
1777 (Siluriformes: Bagridae)
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