Akysis portellus
Ng, 2009 |
he Akysidae family include small and miniature
species which are sexually mature when only 3cm. They are characterised
by their short dorsal fin with a sharp spine, a distinctive adipose
fin, and a broad based barbel developed on the posterior nostril.
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Akysis
portellus |
Akysis portellus is most
similar to A. longifilis,
which occurs sympatrically in the Sittang River drainage.
It is distinguished from A. longifilis in having
a shorter adipose-fin base, smaller mouth and a more rounded
head shape when viewed dorsally.
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|
Akysis portellus
- dorsal
head view
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|
Type localities of Akysis
portellus (triangle) and A.
longifilis (circle)
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All species in this genera possess a venomous
apparatus at the base of the dorsal and pectoral spines and though
not dangerous to a healthy human can inflict a painful sting,
so should be handled with care when being removed from the water
for any reason or during aquarium maintenance.
Like other members of its genera, an
aquaria having a sand substrate interspersed with small rocks
and pebbles mixed with thick clumps of plants would suffice. Unless
feeding, when they are highly active, they can be over looked
in aquaria that has a sand substrate as they like nothing better
than to bury themselves, leaving only their nasal barbels which
protrude slightly from the sand to indicate where they are. So
the next time you see a tank labelled ‘Akysis’
and there appears to be an empty tank, check the substrate to
see if you see any barbels protruding out of the substrate.
Dorsal spines (total): 1; Dorsal soft rays
(total): 4-5; Vertebrae: 32 - 33. It is distinguished from A.
longifilis in having a shorter adipose-fin base, smaller
mouth and a more rounded head shape when viewed dorsally.
In ethanol: dorsal surface and sides of head
medium grayish brown with few darker brown spots randomly scattered
throughout. Dorsal surface and sides of body dark grayish brown.
Belly, chest and ventral surface of head and body light brown. Dorsal
half of body with two elongate saddle shaped light brown spots:
first on body at anterior three-quarters hue over dorsal surface
of head and body.
| Aquarium
Care |
These are ideal catfish
for the smaller sized aquarium. Not difficult to keep but
should really be provided with a soft, sandy substrate since
some of its time is spent completely buried, or with only
eyes protruding. It also appears to enjoy squeezing into
crevices between rockwork and other solid surfaces so additional
decor could include some water-worn rocks of various sizes,
plus perhaps some driftwood roots and branches.
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| Compatibility |
Fish like barbs and rasbora’s make
excellent tank mates, however as they have quite wide mouths,
any fry from livebearers or fish around that size would be readily
predated upon.
There have been reports of their spawning,
but as yet there are no reports of fry development. Several
males were observed with A. vespa
where the male was in pursuit of a gravid female, and the successful
individual was allowed to wrap its body around that of the female
at which point eggs and milt were released. The eggs hatched 4
days post-spawn with the yolk sac fully-absorbed after 10 days.
Adult patterning was fully-developed after just 23 days.
| Sexual
Differences |
Sexing is relatively
easy with the female having larger ventral and pectoral
fins.
|
| Diet |
Feeding does not cause any difficulty,
as long as you use frozen or live foods such as bloodworms, brine
shrimps, white worms and daphnia, as they tend to ignore commercially
prepared foods.
| Glossary
of Terms |
Dorsal spines:
The primary rayed fin(s) on top of the body
Adipose fin: Fleshy finlike projection
without rays, behind the rayed dorsal fin.
Pectoral
fin: The paired
fins just behind the head.
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| Etymology |
Akysis:
A = without;
kysis = bladder, in reference to the lack of a
swimbladder
portellus: From
the Latin portella, the diminitive form of porta,
meaning door. The name is used as a noun and alludes to
the relatively small mouth of this species.
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| References |
Ng, H.H.,
2009. Akysis portellus sp. Nov., a new species of catfish (Teleostei:
Akysidae) from the Sittang River drainage, Myanmar. Journal of
Threatened Taxa 1(1):2-8
Froese, R. and D. Pauly. Editors. 2017.FishBase.
World Wide Web electronic publication. www.fishbase.org, ( 06/2017
)
Wheeler, Alwyne., Fishes of the World - an Illustrated
Dictionary. Ferndale Editions London. 1975. 366p.
www.seriouslyfish.com/species/akysis-portellus/
Taylor, Adrian., http://www.scotcat.com/factsheets/akysis_prashadi.htm
Johnny Jensen
© 
Steven Grant; http://www.scotcat.com/akysidae/akysis_portellus4.htm |
