Catfish of the Month Right March 2002

Synodontis decorus
Clown Syno, Klovneskægmalle (Denmark), Schmuck-Fiederbartwels (Germany) - Synodontis decorus   Boulenger, 1899

Article © Julian Dignall, uploaded March 01, 2002.

Looking back at the list of catfish of the month articles prior to this one (an expanding list - this is the 68th!), I was surprised to find Synodontis decorus was yet to be featured. Time yours truly thought, to right that wrong.

Clown is a name often given to fish, clown anemone fish, loaches and plecos all bear than moniker either because of bold, often brash colouration or because of comical or quirky captive behaviour. This is true of S. decorus too. As juveniles they are amongst the most striking of a genus blessed with some real "lookers" their large black clown spots and horizontally striped flag tail are complemented by lovely black ribbons flowing from their top mast. The fish keep these as they grow and it is a real challenge to the aquarist to stop other fish trying to nibble them.

As ever, there is a catch. Keepers of the oafish beauties often remark on their shyness, appearances in broad daylight are rare and usually limited to feeding time and even then an appearance is not always forthcoming. In the main this is simply put down to the fish being strictly nocturnal - a fact borne out by a fairly large eye size. Oddly however the fishes are often seen being very active in dealers tanks, especially when imported and housed in numbers within the one tank. Perhaps there is more to their reclusivness than straight forward light shyness.

To discuss this, bear in mind two factors. The first is the shoaling, the second eating. Due to its large adult size this fish is not commonly kept in numbers once purchased. Many other Synodontis species become reclusive if kept alone - many are positively gregarious when kept in shoals. The common upside down catfish (Synodontis nigriventris) is a good example of this. S. decorus does not appear to be one of those more aggressive Synos that will rip the fins of other conspecifics (fish of the same species) or even similar fish like other Synodontis species or even other catfish. So if you have a large tank, why not try a group of them?

Second thought is feeding. This fish will eat for all its worth at any given opportunity, typically when housed with cichlids there is a lot of food flying around at feeding time and these catfish are ideally placed to pick up all the scraps, especially after lights out. They will gorge themselves (the size to which their bellies swell can be quite grotesque and has prompted more than one panicky email to this webmaster I can tell you) at any opportunity and then retreat to their chosen cave or pipe to sleep it off. Often the fish will not been seen again for days - it simply has no need to eat or venture into the daylight. Feed your fish less but a little more often (thus keeping non-catfish well fed) and you will see more prowling from your syno.

Other keepers have mentioned other theories to me in the past, another is to keep the fish in tank bare expect for substrate and floating plants. Apparently the Synos remain active all days long, do not become quarrelsome and appear at ease with this set-up.

At the end of the day all these things are worth experimenting with a group of these fish in a suitability large aquarium.

Copyright information for the images used in this article can be found on the species' full Cat-eLog page.

Down Cat-eLog Data Sheet
Scientific Name Synodontis decorus  Boulenger, 1899
Common Names Clown Syno
Klovneskægmalle (Denmark), Schmuck-Fiederbartwels (Germany)
Type Locality Nouvelle-Anvers, Democratic Republic of Congo.
Synonym(s) Synodontis decora, Synodontis vittatus
Pronunciation sin oh don tiss - deck oh rus
Etymology According to Cuvier, Synodontis is an "ancient name for an undetermined fish from the Nile". It is not derived, as often reported, from syn-, together and odous, tooth, presumed etymology of the lizardfish genus Synodus and refers to the closely-spaced lower jaw teeth of both genera. Decora means decorated.
Down Species Information
Size 318mm or 12.5" SL. Find near, nearer or same sized spp.
Identification All species in the genus Synodontis have a hardened head cap that has attached a process (humeral process) which is situated behind the gill opening and pointed towards the posterior. The dorsal fin and pectoral fins have a hardened first ray which is serrated. Caudal fin is always forked. There is one pair of maxillary barbels, sometimes having membranes and occasionally branched. The two pairs of mandibular barbels are often branched and can have nodes attached. The cone-shaped teeth in the upper jaw are short. S-shaped and movable in the lower jaw. These fish produce audible sounds when disturbed rubbing the base of the pectoral spine against the pectoral girdle.

Juveniles have a long filament on the leading dorsal fin ray.
Tan background colouration with black spots.
One of only three Synodontis species (with S. clarias and S. flavitaeniatus) with filaments on both maxillary barbels and mandibular barbels.
Sexing First lay the fish in your hand with its head toward your palm and the tail toward your fingers. Hold the dorsal spine between your middle and ring finger so the fish is belly up and you won't get stuck (Which by the way, hurts like crazy!). The genital pore is in a small furrow of tissue (in healthy fish) and will be obstructed by the pelvic fins. Pull down on the tail gently to arch the fishes spine and the pelvic fins will stand and the furrow open to display the genital pore and the anus of the fish. The male has a somewhat ridged genital papillae on which the spermatoduct is on the back side, facing the tail fin. A gravid female will also show an extended papillae but the oviduct is on the ventral side of the papillae (And may also show a little redness if really gravid). A thin or emaciated female will have just two pink pores, the oviduct and the anus.
Down Habitat Information
Distribution Africa: Congo basin except Luapula River system.
African Waters, Congo (click on these areas to find other species found there)
African Waters, Congo, Lower Congo, Pool Malebo (click on these areas to find other species found there)

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IUCN Red List Category Least Concern, range map and more is available on the IUCN species page. Last assessed 2009.
pH 6.0 - 8.0
Temperature 22.0-28.0°C or 71.6-82.4°F (Show species within this range)
Down Husbandry Information
Feeding Eats crustaceans, algae and insect larvae in the wild. Is not a fussy eater in the aquarium. Will accept flakes and tablet foods. Periodically supplement with frozen food (e.g., krill, brine shrimp and bloodworm) and live food. User data.
Furniture Rockwork, driftwood, sections of pipe with a diameter of 10-12 cm. Grows to about 30 cm, so will need at least a 200 litre tank when it reaches adulthood. This fish does not like bright lights, but with sufficient cover, such as floating plants, it will make the occasional appearance with the lights on. With bright lights, it will sometimes dash out for food, but will otherwise keep itself hidden until the tank is dark.
Compatibility Compatible with all but tiny fish. Can hold its own with large, aggressive fish, but best kept away from fin-nippers which might be tempted to pick at the filament on its dorsal fin.
Suggested Tankmates Large enough to hold it's own in any American cichlid tank, larger individuals will even adapt to African rift lake cichlid tanks. Best kept with larger African characins and barbs.
Breeding Not reported in the aquarium.
Breeding Reports There is no breeding report.
Down Further Information
Reference Annales du Musee du Congo (Ser. Zoology) v. 1 (fasc. 3), pp 49, Pl. 25.
Registered Keepers There are 115 registered keepers, view all "my cats" data.
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There are 24 records of this fish being seen, view them all.
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Last Update 2023 Jan 12 05:31 (species record created: 2002 Mar 01 11:22)

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