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.
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.
Akysis
portellus-
dorsal head view
Type
localities of Akysis portellus
(triangle) and A. longifilis
(circle)
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, anaquaria 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.
Common
Name:
None
Synonyms:
None
Family:
Akysidae
Subfamily:
Akysinae
Distribution:
Asia:
Myanmar.
Known from the type locality in the Sittang River
drainage, southern Myanmar. Type locality:
Shwe Kyin stream, a minor tributary of the Sittaung
(aka Sittang) River system in Bago (formerly Pegu)
Region, southern Myanmar.
Size:
3.5cm (1½ins)
Temp:
18-22°C
(63-71°F)
p.H.
6.5-7.5.
Characteristics
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.
Colouration
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 & Compatibility
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. 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.
Reproduction
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.
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.
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. seriouslyfish.com/species/akysis-portellus Taylor, Adrian.
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