Description:
Like all members of the genus Synodontis, S. omias
has a strong, bony head capsule that extends back
as far as the first spine of the dorsal fin. The head
contains a distinct narrow, bony, external protrusion
called a humeral process. The shape and size of the
humeral process helps to identify the species. In
S. omias, the humeral process is 1+1/2 as
long as it is wide, and has two or three spines directed
backwards. All members of Synodontis have
a structure called a premaxillary toothpad, which
is located on the very front of the upper jaw of the
mouth. This structure contains several rows of short,
chisel-shaped teeth. In S. omias, the toothpad
forms a short and broad band. On the lower jaw, or
mandible, the teeth of Synodontis are attached
to flexible, stalk-like structures and described as
"s-shaped" or "hooked". The number
of teeth on the mandible is used to differentiate
between species; in S. omias, there are 40
to 50 teeth on the mandible. There has been confusion
centered around this species as there has not been
a life-like identification process carried out since
Boulenger in 1911 which the original description by
Gunther was matched to a species from Jebba in the
upper Niger, West Africa. This very well could be
the same species as S.
budgetti from
the upper Niger. The difference between the two species
is that S. omias has a membrane to the maxillary
barbels which S. budgetti lacks but this
could be sexual dimorphism. Habitat:
In the wild, the species has been found in the inland
Niger River basin, although the entire range is not
currently known. Reproduction: The
reproductive habits of most of the species of Synodontis
are not known, beyond some instances of obtaining
egg counts from gravid females. Spawning likely occurs
during the flooding season between July and October,
and pairs swim in unison during spawning. The growth
rate is rapid in the first year, then slows down as
the fish age. Colouration: The body
colour is a uniform brownish. Diet:
As a whole, species of Synodontis are omnivores,
consuming insect larvae, algae, gastropods, bivalves,
sponges, crustaceans, and the eggs of other fishes.
Common
Name:
None
Synonyms:
None
Family:
Mochokidae
Distribution:
Africa:
Niger basin. Type Locality: Jebba,
Upper Niger, West Africa.
Size:
36.0cm. (14½ins)
Temp:
23-26°C (73-79°F)
p.H.
6.5-7.5.
Reference:
Boulenger, George Albert
(1909). Catalogue of the fresh-water fishes of Africa
in the British museum (Natural history). London: British
Museum. pp. 401–402. Cuvier, Georges (1934). The Animal
Kingdom Arranged in Conformity with its Organization,
Volume 10. Translated by Griffith, Edward. London:
Whittaker and Co. p. 406. Ferraris, C.J. Jr.,
2007. Checklist of catfishes, recent and fossil (Osteichthyes:
Siluriformes), and catalogue of siluriform primary
types. Zootaxa 1418:1-628. Poll, M.,1971
Révision des Synodontis africains (famille
Mochocidae). Ann. Mus. R. Afr. Centr., Sci. Zool.,
191:1-497. Seegers, L. 2008 The catfishes of
Africa. A handbook for identification and maintenance.
Aqualog Verlag A.C.S. GmbH, Germany. 604 p.
Synodontis
omias
Image taken at the Porte Dorée Museum in Paris
Synodontis
omias
Line drawing
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