his month (May 2008) we head of to the African family,
Mockokidae, and to one of my favourite genera, the
Syno's and to its most common member, the spotted
catfish, Synodontis nigrita, or as it is
sometimes known as the "false upside down catfish"
owing to the mix up, when youngsters, to the much
smaller and true "upside down cat" Synodontis
nigriventris.
Synodontis
nigrita
This species is
being sold as the all comprising name of "spotted
catfish" or in some cases Synodontis
eupterus which can
look similar when young but have more of a reticulated/striated
pattern. When youngsters (see bottom pic.) their bodies
are adorned with spots including all fins and as they
grow into adulthood they begin to lose this trait
and (as above) take on a change in colour and markings
from a light coloured fish with spots to a dark brown
with less spots. There are always spots that adorn
the fins especially the adipose fin.
Synodontis
nigrita -
juvenile
The holotype speciman resides in the Muséum
National d' Histoire Naturelle de Paris and is a poor
quality speciman although you can just see the spots
in the adipose fin which may have pointed to a spotted
body.
Synodontis
nigrita -
holotype
Another Synodontis
which is alike is the Brown-spotted Syno, Synodontis
robbianus, the difference
is that robbianus seems to keep its spots
into adulthood and attains a smaller size at 13cm.
(5ins). The adipose fin is also larger in robbiana
and does not have the upper lobe longer then the bottom,
but the two can be quite difficult to tell apart.
Can be found
in large lakes and waterways and are widespread on
the African continent.
Common
Name
False
upside-down catfish
Synonyms
Hemisynodontis
nigrita, Synodontis ornatus, S. fascipinna
Family
Mochokidae
Subfamily
Mochocinae
Distribution
Africa:
Chad, Niger, Senegal, Gambia, Casamance, Geba, Kolente
and Volta basins; coastal rivers from Ghana
to Nigeria, Nile basin; including the Bénoué.
Size
17.5cm (6¾ins)
Temp.
21-26°C (69-79°F)
p.H.
6.0-7.5.
Characteristics
D1/7; A4/8-9. Maxillary barbels
longer than the head, not branched, without tubercles
and with a distinct blackish basel membrane. Dorsal
spine not serrate on anterior edge. Caudal fin forked
with upper lobe longer than the lower. Humeral process
keeled and sharply pointed.
Colouration
Brownish, lighter on the belly.
All fins with spots which are arranged as a band on
the caudal fin.
Aquarium
Care and Compatibility
Fine as juveniles but with
most larger Syno's will get a little teritorial going
into adulthood. A 4ft tank or above with larger tankmates
such as Rasboras, African tetras or Cichlids will
do fine.
Reproduction
In their natural
habitat they are nonguarders of their eggs and as
substratum egg scatterers they will scatter them in
open water. Not bred in aquarium so far but some have
turned up as hybrids, crossed with other Syno species
from Eastern Europe.
Sexual
Differences
Not apparent but the females
will be deeper bodied than the males.
Diet
As with most of the Synodontis
genus they will accept a wide range of foods and can
be fed on a good quality flake, tablet, pelet and
frozen foods such as bloodworm.
Glossary
of Terms
Dorsal:
is defined as being top or above.
Holotype: The
specimen on which the description of a new species is
based. Humeral process: Bony
extension of the pectoral girdle.
Maxillary barbels: Pertaining to the
upper jaw (maxillary barbels). Tubercles: Tentacle-like
projections.
Etymology
Synodontis:
Ancient name for an undetermined fish from the Nile
(Cuvier 1816). nigrita:
Blackened.
References
Morris,
P.J. [programmer] and M.H. Sabaj
[editor], 2006. ACSImagebase: A digital archive of
catfish images compiled by participants in the All
Catfish Species Inventory. Sterba, Günther;
Freshwater Fishes of the World
vol.1 t.f.h. p408-9. Stiassny, L J Melanie;
Teugels, G. Guy; Hopkins, D. Carl;
The Fresh and Brackish Fishes
of Lower Guinea, West-Central Africa. Vol.1 p739-40.
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