Clarias gariepinus?

Caol_ila · Post by **Caol_ila** » 04 Oct 2004, 19:41

Hi!

Bought this labeled as "Wels - Ictalurus ssp. AMK <---might mean "Amerika" pretty obvious they just took a catfish label.
But what species is it?

It wasnt very tasty i have to admit...

Post by **Silurus** » 04 Oct 2004, 20:05

Certainly a gariepinus.

Post by **medaka** » 04 Oct 2004, 22:34

on the first photo the dorsal looks like its split down the lower third of its length; or is it a dorsal followed by adipose fin .

if it is it may well be
hetrobranchus longifilis

Post by **Silurus** » 04 Oct 2004, 22:36

Naw, It's a completely-rayed dorsal fin.

Caol_ila · Post by **Caol_ila** » 04 Oct 2004, 23:39

It only looks like its an adipose...couldnt get Nici to help me make some better pics...she doesnt like dead meat that looks at her

beng · Post by **beng** » 05 Dec 2004, 20:50

Silurus wrote:Certainly a gariepinus.

It looks a lot like the mystery Clariids i saw selling in the fishmonger near Leicester square (London Chinatown), but the head is a lot rougher than the larger Clarias gariepinus that i caught in Singapore, and it is a lot flatter too, like its been squashed.

Post by **Silurus** » 05 Dec 2004, 20:55

Clarias gariepinus have somewhat flattened heads. This is more evident in larger fish:

beng · Post by **beng** » 05 Dec 2004, 21:02

On this page:

http://www.fishingkaki.com/forum/viewto ... gariepinus

are a couple of pics of what i thik is a C. gariepinus that i caught in Singapore, it was a male, 49cm TL, caught on hook and line using an introduced neo-tropical cichlid as bait. Singapore is an interesting place, you have African catfish fish in an Asian country eating Central American cichlids. Anyway it looks lighter in colour than the fish here and with a marbled pattern, and the head surface is not as rough, and the head is not so flat. Is mine a gariepinus?

I put it in my 4 foot tank but it jumped out and i found it dried up on the floor. I thought it was dead but when i put it in the water it came back to life and seemd alright.

beng · Post by **beng** » 05 Dec 2004, 21:10

I just added a side view of the head on the catfish i caught at the above link. Its flat, but not as flat as the black fish in the pic on this page. Maybe the fish monger bashed its head in to kill it?

Post by **Silurus** » 05 Dec 2004, 21:31

I remain to be convinced that C. gariepinus is a single pan-African species. I know of genetic evidence that divides what is currently recognized as "C. gariepinus" into three (northern, central and southern African) lineages.

Therefore, I would expect a fair amount of plasticity in morphology among what is now called C. gariepinus.

beng · Post by **beng** » 05 Dec 2004, 22:17

According to this link:
http://www.fao.org/DOCREP/003/W3595E/w3 ... 20Taxonomy or
http://www.nefisco.org/downloads/Clarias.PDF

C. gariepinus used to be considered 4 different species:

Â· Clarias senegalensis
Â· Clarias lazera
Â· Clarias mossambicus
Â· Clarias gariepinus

Why did they lump them together as C. gariepinus? What makes one species different from (or the same as) another? At the other end you have the Asian C. batrachus which is thought to be several species but still lumped under one species name. And the Clarias species seem to be able to hybridise and produce fertile offspring, so that the Thai C. garipinus x macrocephalus hybrids can breed their genes into the wild gene pool. Could we then say that macrocephalus and gariepinus are just different varieties or sub-species of the same species? Like Thai people and Africans are the same species though they live on different continents and look different?

Anyway the Asian gariepinus population seems to have come from the Central African Republic which is in the part north of the Congo river labelled in the map as the distribution of what was formerly called C. lazera, the north african and Western Asian population.

I wonder where the black, rough-headed clariids imported into the European food market come from. Colour wise they look more like the photos of garipinus from South Africa which are black. But again colour may be variable even in the same individual depending on time of day, substrate colour, etc.

Post by **Silurus** » 06 Dec 2004, 03:12

Why did they lump them together as C. gariepinus?

Because the purely morphology-based analysis that was used [in Teugels, 1986: A systematic revision of the African species of the genus Clarias (Pisces: Clariidae)] doesn't work very well in distinguishing cryptic species (as I believe may be the case here).

coelacanth · Post by **coelacanth** » 06 Dec 2004, 09:29

beng wrote:
Silurus wrote:It looks a lot like the mystery Clariids i saw selling in the fishmonger near Leicester square (London Chinatown), but the head is a lot rougher than the larger Clarias gariepinus that i caught in Singapore, and it is a lot flatter too, like its been squashed.

If they were fresh they were probably Taiwanese-bred C. gariepinus (or so I've been informed, they do taste a little bit muddy from there which is probably due to the type of enclosure they are reared in and the quality of the food they are given.
The rougher head may be due to slight freezer drying while in transit.

I think the smoked ones now commonly available over here may originate in Nigeria.

beng · Post by **beng** » 06 Dec 2004, 10:21

I have just found out that gariepinus is being farmed for food in the EU as well, in the Netherands from West Africa:

http://www.fao.org/docrep/X5628E/x5628e ... 0clariidae

http://edelwels.nl/

and in Belgium:
http://66.102.9.104/search?q=cache:NvSR ... .htm&hl=en

beng · Post by **beng** » 06 Dec 2004, 10:34

The first link above also says they have been introduced to Cyprus from Israel as sport fish.

The http://edelwels.nl/ site says the Dutch fish originate from central Africa.

According to Fishbase the Central African Republic has been a major source of gariepinus introductions in other countries:

http://www.fishbase.org/Introductions/I ... kcode=2130

And also the fish have been introduced to Hungary, Poland, France, Czechoslovakia, Slovakia, Greece, and Russia!

I wonder if they will end up in the aquarium trade in Europe too.

beng · Post by **beng** » 06 Dec 2004, 13:57

Here is a a link about the Hungarian gariepinus operation, they use geothermal energy to warm their water:

http://www.tve.org/ho/doc.cfm?aid=979&lang=English

They say catfish tastes better than sea fish, and the Dutch keep theirs in clean water for 3 days prior to slaughtering, so the mud taste of the UK carcasses and the one in Germany might suggest they come from pond reared stock in some tropical country that wasn't kept in clean water for a few days to leech out the mud flavour before slaughtering.

And here is a link about a Brizilian gariepinus farm:

http://www.pondfish.com.br/ingles/especie.html