Aspistor quadriscutis
(Valenciennes, 1840)
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oining us this month (June 2011) is David Marshall with an in
depth look at the Bressou sea catfish from the Ariidae family
and a catfish that is not often seen or discussed in aquarium
literature. David is a show judge and also editor of The
Aquarium Gazette, a CD based aquarium publication in the
U. K. and distributed worldwide. We will let David carry on
from here with his look at the 'Bressou sea catfish'.
In 2004 TAG contributor Jackie Goulder
phoned, in a very excited voice, to let me know that some kind
fishkeeper had literally dropped onto her doorstep an unknown,
and very large, catfish. Now this fish I had to see so Jackie
arranged to collect me and down to Flamingo Land we went for
a ‘night visit’ (which you can read all about on
the Aquarticles website at www.aquarticles.com). When my eyes
fell upon the wonderful catfish pictured above, I was truly
amazed.
From first sight I could tell that the
large catfish was an Ariid of some type and it had a resemblance
to the large Asian catfish 'Mystus' wyckii. Armed with
e-mail friendly copies of Jackie's photographs I contacted several
'catfish experts' and asked for their help in providing some
clues as to the exact identity of the Flamingo Land Ariid. As
I really should have guessed TAG contributor Steven Grant was
the only person to reply and left me with the following lead
(the reference to Mystus comes from my comments that
the Arrid had a look of 'Mystus' wyckii.
"‘Hello David - Yes it's difficult
to tell from a photograph but it does look like an Ariid. Mystus
wyckii (now known as Hemibagrus wyckii ) has long
maxillary barbels. My closest guess from the photos is Aspistor
quadriscutis (used to be in Arius) but it is only
a guess. The only sure way of identifying it is drawing/photographing
the cephalic shields (Head plates), and also if possible the
tooth patches but this is virtually impossible in live fishes.
- Regards Steven".
Searching through textbooks revealed
that Valenciennes scientifically named Aspistor quadriscutis
in 1840. The only other member of this
genus is A. luniscutis. A. quadriscutis has
a natural distribution from north west Guyana through to northeastern
Brazil (off Orinoco Delta) with unconfirmed reports placing
it around the coastline of Venezuela. This fish is known commonly
as the Bressou Sea Catfish but is equally at home in brackish
and freshwater environments. Unlike many members of the Arius
grouping this fish does not have a 'shark catfish' tag. The
exact spawning ritual is unknown but eggs are orally incubated
by the male.
I was absolutely thrilled to get this
far, having never heard of the scientific name, so began to
cross-reference the above on the 'search' facility of our Internet
supplier. I did not expect to find much more information than
had already come to light so was thrilled when 12 sites were
revealed as possible sources of further bits and pieces about
Aspistor catfish. From the first eleven sites the information
we already had was confirmed and the following points added:-
- The Bressou Sea Catfish had been the subject of scientific
research on sustainable food resources on two occasions.
- Ichthyologists had been unable to find
a definite way of telling males and females apart.
- This fish is sold fresh for human consumption via wet fish
stands while exported frozen to countries of unstated origin.
- Usually has various bottom-dwelling invertebrates found among
its stomach contents.
Now with site 12 left to view I expected
to find very little else to report upon so imagine my joy when
the FishBase org., first time I had visited this site, had a
wonderful two page information sheet on the Bressou Sea Catfish
that had been compiled by A. P. Marceniuk and C. J. Ferrais
Jr. After reading this sheet I was able to confirm that the
Flamingo Land monster was indeed Aspistor quadriscutis.
Although the only photograph with the
file was of a museum specimen, this fish, which looked like
a deflated version of our photographs
and lacked natural colour, looked very similar and fins and
whiskers certainly appeared to match. The description talked
of 3 pairs of barbels on rostral region, 2 pairs on lower jaw,
a single pair posterior end of maxilla and of the fish having
a large saddle-shaped bony plate with rugose surface in front
of dorsal fin. Although the body colour is quoted as more yellow
in appearance this could be to do
with pigmentation increase due to a natural food source?
The Bressou Sea Catfish is found in turbid
waters over muddy bottoms in shallow coastal areas, also around
estuaries, and coastal rivers.
In aquaria Jackie found the Bressou Sea
Catfish to be no trouble in the company in which it was kept,
that ‘he’ fed from her fingers and was a real ‘pet’
(as many large catfish can become). Sadly, a few weeks before
Jackie retired from her work, a second phone call was
received informing me that very suddenly, and without warning,
the Apistor catfish had died. How this fish had come into the
U.K. we never knew and no aquatic retailer I have spoken with
have found this fish on their list from wholesalers. So it looks
as though our Apistor most likely came in as a ‘contaminant’
with more readily available South American catfish? ‘He’
was a unique fish and putting together this article reminded
me of all those wonderful evening visits to Flamingo Land in
which Jackie, Sue, the members and
friends of Ryedale Aquarist Society (on occasions) had ‘free
wander’ of the wonderful aquarium and Zoo.
Remarks: Ariids are found
worldwide in tropical to warm temperate zones. They are unusual
among catfish in that they live primarily in the sea and thus
are found along the coastlines of the America’s, Africa,
Asia and Australia. Many species are also present in freshwater
habitats; some species only occur in freshwater. In North and
South America about 43 species extend into brackish water or
are found exclusively in freshwater. Doilichthys is
another freshwater species that is found in New Guinea. The
scientific classification of the Arrids is something of a ‘muddle’
and we will mention more about this in a forthcoming article
on Shark catfish.
This article was published in The Aquarium
Gazette no. 19. visit TAG
Dorsal spines (total): 1. Three pair of
barbels on rostral region, two pairs on lower jaw, one pair on
posterior end of maxilla; end of maxilla barbel reaching pectoral
fin insertion; large saddle-shaped bony plate with rugosa surface
in front of dorsal fin, anterior margin of this plate waved but
no deep medial incision.
Body yellow or gray-yellow dorsally, white
ventrally.
In aquaria Jackie found the Bressou Sea
Catfish to be no trouble in a large aquarium in which ‘he’
had an Xanthic Giant gourami and several large Pacu for company.
'He' fed from her fingers and was a real ‘pet’ (as
many large catfish can become).
Reproduction period is probably between
September and November. Egg diameter is 9-11 mm. Males practice
mouth brooding of the eggs.
| Sexual
Diferences |
The sexes can be
told apart, at the right time of the year, in this respect
due to a bulging male mouth.
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| Feeding |
Raw marine fish with a lettuce and carrot
side salad formed the favoured food dish.
| Etymology |
quadriscutis
: Four spined.
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| References |
Froese, R.
and D. Pauly. Editors.
2009.FishBase.World Wide Web electronic publication.www.fishbase.org,
version (05/2011).
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| Glossary |
Rugose :
Covered in ridges, knobs or protuberances, deeply wrinkled
etc..
Dorsal fin: is defined as the medial
fin on top of the back.
Mandibular barbels: pertaining to the
lower jaw. (mandibular barbels)
Maxillary barbels:
pertaining to the upper jaw. (maxillary barbels)
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| Photo
Credits |
Jackie Goulder
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