atasio species are small, laterally compressed bagrid
catfishes generally found in fast-flowing hill streams throughout
South Asia, Myanmar, the Salween and Mae Khlong drainages of Thailand
and the northern Malay Peninsula. Batasio havmolleri (Smith,
1931) is currently considered a junior synonym of B. fluviatilis.
They are diagnosed (together with Chandramara)
from other members of the Bagridae in possessing large sensory
pores on the head, a narrow mental region, the transversely
elongated, bar-like entopterygoid, and the close contact of
the metapterygoid with the quadrate (Mo, 1991). Batasio
is distinguished from Chandramara by the absence (vs.
presence) of a pair of prominent posterior processes on the
anterior part of the vomer.
Batasio fluviatilis Occurs
in rivers and streams with moderate to swift current and
a predominantly rocky bottom; less often in slow-flowing
streams with a muddy substrate. Hides among stones or submerged
vegetation during the day and comes out at night to feed.
Adult with young - note
the juvenile body pattern
Dorsal spines (total): 1; Dorsal soft rays
(total): 7; Anal spines: 4-5; Anal soft rays: 8 - 9. Differs from
Batasio merianiensis by having length of adipose fin base
30.0-33.3% SL (vs. 22.2) and eye diameter 18.2-23.5% SL (vs. 25.9)
U. K. aquarist
Stuart Brown has successfully spawned B. fluviatilis.
Below is a short account of his thoughts and above image shows
an adult and youngsters. As with most catfish the juveniles
will show a different colour pattern until growing into adulthood.
"Cleaning out the filter
sock on my sump and I find three stowaways. Obviously the big
one ( inch and a bit) is from the first spawning. I would say
the 2 smaller ones are about 2-3 weeks old. Seems large water
changes are the trigger, coupled with the changing weather perhaps".
(Original text from FB Group: Catfishes
of the World. www.facebook.com/groups/CatfishesoftheWorld)
Distinguished from all other species of the
genus Batasio, except Batasio merianiensis in
having an adult colouration consisting of a dark oblique predorsal
bar and a dark spot on the sides of the body below the middle of
the adipose-fin base.
really suitable for your usual community tank as they will
need special conditions such as good water flow and a cooler
temperature. Good water conditions should be adhered to
at all times with regular water changes to keep organic
waste down to a minimum. A sand and gravel mixed substrate
with scattered rocks/boulders and root works would be ideal
for a good water flow. In their natural habitat plants will
not be present but hardy plants such as Microsorum,
Bolbitis or Anubias spp., can be grown
attached to the decor (Source: SeriouslyFish)
Not especially competitive and should not
be kept with much larger or more aggressive fishes. Suitably-sized,
peaceful, schooling cyprinids are ideal, or if geography isn't’t
an issue many characids and livebearers should also work. In addition,
balitorid loaches from genera such as Gastromyzon, Pseudogastromyzon
and Homaloptera are suitable, and some members of the
families Cobitidae and Nemacheilidae should also be ok but proper
research is essential as some can be excessively aggressive/territorial
or simply grow too large.
An egg scatterer. See above.
Feeds readily on any type of the usual fish
foods, flakes, granulated food, frozen or live food
|Males possess a clearly
visibly, elongate genital papilla anterior to the anal fin.
Fleshy finlike projection
without rays, behind the rayed dorsal fin.
Dorsal fin: The primary
rayed fin(s) on top of the body
Anal Fin: The median, unpaired, ventrally
located fin that lies behind the anus, usually on the posterior
half of the fish.
Entopterygoid: A paired bone articulating
with the palatine in front.
Metapterygoid: Posterior bone that ossifies
in the cartilaginous palatoquadrate arch. It first appears
as a rod of bone with an anterodorsally projecting process
from the middle of the dorsal surface (6.4 mm). The adult
metapterygoid is roughly rectangular in shape with rounded
corners and an anterodorsally projecting spine that meets
the entopterygoid medially in a synostosis at its posteromedial
edge. The posterior end curves dorsally to form the posteroventral
surface of the orbit.
Palatine: The teeth present on the palatine
bone which lies laterally in the roof of the mouth.
Vomer: The anterior bone in the mid-line
of the roof of the mouth.
From the local (Bengali) name
of the fish (batasio or batashi).
|Ng, H.H. and M.
Kottelat 2001 A review
of the genus Batasio (Teleostei: Bagridae) in Indochina, with
the description of B. tigrinus sp. n. from Thailand. Rev.
Suisse Zool. 108(3):495-511.
Ng, H.H. and M. Kottelat 2007 Batasio feruminatus,
a new species of bagrid catfish from Myanmar (Siluriformes:
Bagridae), with notes on the identity of B. affinis and B.
fluviatilis. Ichthyol. Explor. Freshwaters, Vol. 18, No. 4,
Darshan, A. , N. Anganthoibi,
and W. Vishwanath, 2011 - Zootaxa 2901: 52-58 Batasio
convexirostrum, a new species of catfish (Teleostei: Bagridae)
from Koladyne basin, India.
FB Group: Catfishes of the World.
© Allan James @
Bottom: © Stuart Brown