n our ‘hobby’ Synodontis
robertsi is usually sold under its scientific name
as opposed to the common names of Robert’s Synodontis
and Large blotch Synodontis. In the wild this fish hails
from Central Congo, Lukeria and the Egobe river system.
Synodontis robertsi is a member of the Mochokidae
family. The Mochokidae lack the protection of body scutes
(which you will know through Corydoras) so nature
compensated by the provision of a continuous bony shield
that runs from behind the eye to the dorsal fin spine that
deflects all but the hardest blows from the teeth and bills
of aquatic living mammals and fishing birds respectively.
Although I have heard no reports of
a robertsi squeaking (backed-up by the fact that
squeaker does not appear in the common names quoted above)
when removed from water this is a secondary defence system
among the majority of Synodontis species.
As with all Synodontis the pectoral fin spines
are a ‘wonder of nature’. Very sharp they also
afford protection (watch your fingers) while recording growth
like the rings of a tree. The pectoral fin bone of each
Synodontis species is different so becomes a ‘signature
tune’ allowing ichthyologists, once the flesh is removed,
to tell the true identity of species which may look alike
to the naked eye.
A fact file on the Planet Catfish web-site describes the
body pattern of our subject specie as ‘giraffe-like’
and although I go along with this the pattern of dark brown
and white varies greatly among individuals (as readers who
know the more commonly seen Synodontis angelicus
will be familiar) going from crop circle markings to bars
as in Synodontis brichardi. The body, which can
reach a maximum size of 16cm, has a raised appearance like
that of Synodontis contractus - with whom large
‘alberti eyes’ are also shared.
Considering the likeness to Synodontis contractus,
which has plainer and bland body colours in comparison,
there is little wonder that one can be offered for sale
as the other. The body colours of Synodontis caudalis
(forked caudal lacking in robertsi) and certain
colour variants of Synodontis schoutedeni (smaller
eyes and more yellow colour in body) also lead to these
two species occasionally offered for sale as robertsi.
To see both the likenesses and differences between the mentioned
species visit the fact files and photographic galleries
on both the Scotcat and Planet Catfish web-sites.
Before moving onto aquarium care we must note that our subject
specie can be very delicate and one which, despite great
care, sometimes never settles into aquarium life literally
dwindling away. This is often signalled by the onset of
lethargic activity, at which time the robertsi
will sit close to the front of the aquarium and find a spot
from which the only movement will be tiny rocking motions.
The roots of such demise are often:-
1. A failure to feed. Robertsi
can go on ‘hunger strike’ following exportation,
which also occurs with certain ‘L’ numbered
loricarins, and once out of the eating habit may never
resume this vital practice. If you are on good terms with
your local retailer always ask to see a robertsi
feed prior to purchase.
2. The shock of ‘new water’.
Because of their delicate nature robertsi need
to be placed into a well established aquarium, with excellent
filtration, in which only minimum water changes are made.
Aquarium care begins with a minimum sized
aquarium of 60x30x30cm. The aquarium should be well filtered
with a pH between 6.2 and 7.5 and temperature in the range
of 23 to 27 C. For décor well plant the aquarium
and provide shelter in the form of Mopani wood, broken
plant pots (which should have smooth edges as the skin
of robertsi is softer than it first appears)
and small ceramic pipes. Medium-sized African characins
make good companions. As robertsi are a riverine
species they should not be kept alongside Rift Valley
cichlids. When eating they will take small living foods
and commercial flakes.
Taking the contractus and alberti (Albert’s
catfish) likenesses very seriously it may well be that,
like these two species, robertsi does not have
the long natural lifespan, sometimes in excess of 20 years,
that is enjoyed by a number of Synodontis including
the well known decorus (Clown squeaker) and eupterus
Sadly there are, as yet, no reports
of robertsi reproducing within the confines of
aquaria. Field reports suggest that distinct pairs form,
during the Congo rainy season, and that, in open water,
dark coloured eggs are scattered over the available substrate.
As a final point we must mention that Synodontis robertsi
are not always readily available so their price in aquatic
retail outlets can be very high – in some cases
topping that asked for Synodontis angelicus.
Kevin Webb : S.robertsi