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Pseudacanthicus looking for identity

Posted: 25 Oct 2006, 20:16
by Judazzz
Hey everyone,
yesterday I bought myself a new pleco (almost two for that matter, but 70 euro's for a 6" Snowball was a bit too much), and I was wondering about its identity. I do have my own ideas, but I'd rather hear some suggestions from you guys too.

The fish is about 5-6" in size, cost me 40 euro's, and has a disposition that really stunned me: I've seen weird, gutsy and aggressive pleco's in the past, but this nutcase takes the cake. At the store he jumped the front tank wall as soon as I got near, putting him in a bag was a huge struggle, and once back home, it took just an hour or so before he started eating, and more importantly, started fighting with my larger L114 and Sultan Pleco. Fear is something that apparantly doesn't feature in his dictionary, because I had to physically restrain him from taking another jab at his tank mates - in most cases pleco's run, but this guy simply rammed my hand, or dodged it to try to continue his fight :shock:
So I let them just go on with their business - things like these have to sort themselves out anyways, as it is the nature of the beast. And luckily things seem to have settled down over night, as he and his tank mates all had a nice little hiding place to call home and tried to ignore each other. The frailed fins will heal quickly, I expect...

Anyways, enough anecdote mumbo-jumbo, time for some pictures - and hopefully an answer to the question what species this fierce Pseudacanthicus is:

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And a close-up - I suspect it's a boy...

Posted: 25 Oct 2006, 20:59
by Cristoffer Forssander
Hi!

I would say L114!

A beautiful catfish!


Regards
Cristoffer

Posted: 25 Oct 2006, 21:18
by Marc van Arc
Yes, I'd say that too:

Posted: 25 Oct 2006, 22:05
by racoll
As far as I know L114 and P.leopardus may not the same species.

The L114 is from the Rio Demini off the Negro in Brazil, while the P.leopardus is from the Rio Rupununi in Guyana.

As they are from different drainages they may perhaps be different species.

They are treated seperately in Wels Atlas II, but unfortunately I can't read the text.

The fish is question looks like a P.leopardus as there is much greater amount of orange in the caudal and dorsal fins, although this will vary between individuals.

Beautiful fish whatever it is


:D

Posted: 26 Oct 2006, 10:32
by Jools
racoll wrote:As far as I know L114 and P.leopardus may not the same species.
Yeah, kind of. P.leopardus was described where the "L600" species came from, therefore that's almost certainly the right species. Whether L114 is that species or a similar one, isn't scientifically defined but they are probably separate and that's the view in WelsII. I just haven't changed the catelog to reflect this.

Look at the headwaters of the two rivers on a good map...

Jools

Posted: 26 Oct 2006, 14:50
by Judazzz
Ik too use the Mergus Wels Atlas as one of my sources, and this fish does seem to resemble what they call Pseudacanthicus leopardus (aka. Leopard Cactus Pleco -- is that the same as L600, btw?) much more closely than L114 Pseudacanthicus sp./Pseudacanthicus cf. leopardus (aka. Demini Leopard Cactus Pleco).
He shares his tank with two (smaller: 1,5" and 4") L114, and he does look very different: the overal body shape, the body color and facial pattern, the coloration of the fins are all quite distinct.
Here's a direct comparison between the three:
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The new fish (plusm. 5-5,5")

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Larger of the two L114 (plusm. 4")

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Smaller of the two L114 (plusm. 1,5")

According to Mergus, P. leopardus is found in the Rio Essequibo and Rio Rupuni (Guyana), and in the Rio Branco and Rio Takutu rivers in Brazil. That is on both sides of a water divide in the border region between Brazil and Guyana. The two Brazilian rivers drain into the Rio Negro, while the Guyanan (sp?) rivers flow towards the Atlantic coast. So two different populations?
L114 is found in Rio Demini, also a river that drains in the Rio Negro. I haven't been able to find a map of it, but imo. it would be interesting to know where it flows, in relation to the rivers that drain into the Rio Negro in which P. leopardus is found, as it may give us some clues about L114 in comparison to P. leopardus from both the Brazilan and Guyanan part of its locality...

Posted: 26 Oct 2006, 16:15
by Yann
HI!

According to Ingo Seidel, P.leopardus is different from L114 on the following point
-More elongated head
-Smaller dorsal fin
-Brighter and more extended orange/red coloration
-smaller head spots that tends to vanish with age
-overall body colour: green grey vc brown grey

Cheers
Yann

Posted: 28 Oct 2006, 15:48
by Judazzz
yannfulliquet wrote:HI!

According to Ingo Seidel, P.leopardus is different from L114 on the following point
-More elongated head
-Smaller dorsal fin
-Brighter and more extended orange/red coloration
-smaller head spots that tends to vanish with age
-overall body colour: green grey vc brown grey

Cheers
Yann
My new fish does match a number of those features (facial pattern, red coloration), but not all... :?
Does it mention anything about the coloration of the tips of the lower fins? My new fish appears to have orange tips on its ventral and anal fin, which the L114's do not have.
Man, this is tough...

One more thing that keeps mymind occupied in these affairs: how reliable is the Mergus Atlas? I know a number of the more knowledgable and well-known people in the field have contributed, but I also know that this "Datz-group" is at odds with Armbruster on quite a number of issues. If I'm not mistaken, the Mergus/Datz-people themselves are advanced hobbyists/collectors rather than ichthyologists (as Armbruster is), right? So who to believe/follow?