here
is a school of thought that the Ageneiosus
genera should be in its own family of Ageneiosidae
(Walsh and Eschmeyer, 1990) but the thirteen species
in this genus have been placed in the Auchenipteridae
family ( Ferraris, 1988a) with Auchenipterinae as
the sub-family. In addition to this Walsh also feels
that A. magoi
is a synonym of A.vittatus.
Ageneiosus
magoi
- adult male
As you can see
by the above image that this is indeed a very pretty
species but beware as
it is very predatory, as all Ageneiosi are, and would
need to be housed in a large tank of 6ft (180cm) or
over. This is one of the smallest of the Ageneiosus
but they do need a lot of swimming space especially
if keeping more than one.
As mentioned,
a good sized aquarium furnished with driftwood and
high plants around the edges. The type of substrate
is not too much of a problem but will need good fltration
with a external filter the best option. The main criterea
is to give them plenty of swimming space as, unusual
for this family, they will swim about sometimes during
the day.
The other common
names of this sub-family apart from Slopehead catfishes
are "bottlenose" or "barbelless catfishes".
Ageneiosus magoi only possess very small
maxillary barbels but in common with the rest of the
Auchenipteridae family
the males possess an elongated and thickened anal
fin, a genital papilla. The male has it modified into
a copulatory organ with the first and second ray thickened
and longer, it is thought that the male uses this
to clasp the female during the spawning embrace.
Ageneiosus
magoi:showing
the lack of any discerning barbels.
Common
Name:
Slopehead
Catfish
Synonyms:
None
Family:
Auchenipteridae
Subfamily:
Auchenipterinae
Distribution:
South America:
Venezuela; Orinoco basin.
Type locality: Los esteros de Camaguán,
km 270, Estado Guárico.
Size:
24.0cm. (9½ins)
Temp:
23-28°c (73-83°f.)
p.H.
6.5-7.2.
Characteristics
Head flattened and wedge shaped.
Profile almost straight, sloping slightly towards
snout. Dorsal 6/7 rays. Small adipose fin and a long
anal fin. The ventral fins are placed behind the dorsal
fin and has 7/8 rays. Eyes
lateral.
Colouration
Marbled markings to body.
Two black bands along body split by a white band.
Some specimens have a yellow tinge but may lose
this in captivity. There can be differences in seperate
individuals.
Aquarium
Care & Compatibility
If kept with other species
they would need to be the same size or larger species,
such as Loriicarids and larger Characins such as Silver
Dollars. Can be kept
with equal sized conspecifics.
Reproduction
There are no documented
reports of aquarium spawnings.
Sexual
differences
In common with
the rest of the Auchenipteridae family
the males possess an elongated and thickened anal
fin, a genital papilla. The male has it modified into
a copulatory organ with the first and second ray thickened
and longer, it is thought that the male uses this
to clasp the female during the spawning embrace. Sexually
active males also have
an elongated and curved dorsal spine and the maxillary
barbels are also elongated.
Diet
Primarily
meat eaters so will need this somewhere in their diet.
Earthworms, shrimp, beafheart and fish flesh would
be an adequate diet.
Glossary
of Terms
Dorsal fin
is defined as the medial fin on top of the back. Adipose is defined as a second dorsal
fin. Anal fin is defined as the medial
fin immediately posterior to the anus. Ventral fins are defined as the paired
fins between the pectoral and anal fins. Dorsal is defined as being top or
above. Maxillary is defined as being in
relation to the maxilla, the bone of the upper jaw
Etymology
Ageneiosus:Beardless, pertaining to the very small maxillary
barbels. magoi: In honour of Francisco
Mago-Leccia (1931-2004), for his contributions to
the study and knowledge of Venezuelan fishes, and
his valuable work forming a new generation of ichthyologists.
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