Description:
The main description for A. biscutatus is
that the body and adipose fin in adults is either
light brown or grey with small, distinct spots on
the rayed fins that do not form bands. The shape of
the nuchal plate is also distinctive from all other
congeners in the genera. The species depicted in the
first thumbnail image was originally thought to be
a a juvenile of A. occidentalis. Habitat:
Commonly occurs in running water, lakes and submerged
vegetation in the Sudd, rare in fringing vegetation.
Diet: Feeds on the bottom on mud,
debris, insects, notably chironomid larvae and mollusks.
Reproduction: Gravid fish are recorded
throughout the year with a peak in the dry season.
Teugels et al. (1991) considered the genus Auchenoglanis
to be comprised of two valid species: A. biscutatus
and A. occidentalis.Due to the
work carried out recently (2010) by Michael Retzer
there are now 8 in this genus with six new species,
A. acuticeps,
(now considered a synonym of A. occidentalis)
A. biscutatus,
A.
occidentalis,
A. sacchii, A.
senegali, (now considered a synonym
of A. biscutatus) A.
tanganicanus, A.
tchadiensis and A.
wittei. Abstract:
The taxonomic history of the African catfish genus
Auchenoglanis includes eight nominal species,
with two of these, Auchenoglanis biscutatus
and Auchenoglanis occidentalis, being recognised
as valid by most authors. The validity of all eight
species was recently established based on mainly pigmentation-related
characters and the shape of the premaxillary tooth
plates. As these results opposed previous works but
lacked any mention of these, the species diversity
in the genus was re-evaluated based on biometric,
meristic and other morphological data. It reconfirms
the status of only two valid species within the genus.
Auchenoglanis occidentalis ranks among the
African fish species with very large distribution
areas, being present from Senegal to Tanzania. Auchenoglanis
biscutatus is distinguished from A. occidentalis
by a postorbital head length that is greater than
the preorbital head length, an adipose fin that rises
abruptly, and a maxillary barbel with a tip not darker
than the head colour (Geerinckx &
Vreven 2013).
Remarks:
A. senegali Retzer, 2010 is now considered
a synonym of A. biscutatus.
Africa: Rivers
Nile, Niger, Senegal, Lake Chad Basin and Gambia basin.
Size:
54cm. (17½ins)
Temp:
24-26°C (75-79°F)
p.H.
7.0-8.0
Reference:
Retzer E. Michael;
Taxonomy of Auchenoglanis Günther 1865 (Siluriformes:
Auchenoglanididae) Zootaxa 2655: 25–51 (2010). Bailey, R.G. 1994 Guide to the fishes
of the River Nile in the Republic of the Sudan. J.
Nat. Hist. 28:937-970. Tom Geerinckx & Emmanuel Vreven
(2013) A re-evaluation of the species-level diversity
within the catfish genus Auchenoglanis (Siluriformes:
Claroteidae), Journal of Natural History, 47:47-48,
2979-3010.
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