Cephalosilurus ID

[Jarcave]

Anyone fancy id'ing this Cephalosilurus? This one was sold as apurensis, however I'm being told by an apurensis owner that it is nigricaudus. You're thoughts please, and thanks in advance.

[yellowcat]

Presumably this is the same fish that came from Peru? It is most likely c. apurensis and appears so from the photos. C. nigricaudus exist in Suriname so it's unlikely one would be transshipped to Peru. C. nigricaudus (latin translation is "black tail"), have distinctly black colouration on the back half of the fish in juveniles at least, which doesn't appear to be the case with your fish. Always looking for uncommon cephalosilurus species like c. nigricaudus and c. transmontanus (Guyana) but never seen them for sale...

[Jarcave]

No. This is from elsewhere. This was sold as apurensis. I think it's apurensis, we know it's deffo not albomarginatus or fowleri. However another keeper of apurensis suggested this is not apurensis which I believe it to be, hence me seeking other opinions. Hope that makes sense.

The two fish from Peru sold within 48 hours of being advertised as apurensis.

[yellowcat]

First a correction, no such thing as c. transmontanus, I confused it with batrochoglanis transmontanus, I meant c. albomarginatus as you've mentioned. A great source on cephalosilurus is Wolfgang Ros who's kept 3 of the cephalosilurus species and has written several articles about same. He has mentioned the subtle differences between c. nigricaudus and c. apurensis and notes that sometimes c. apurensis can exhibit darker coloring as juveniles and that c. nigricaudus can lose some pigmentation as they grow. I've found that as juveniles c. fowleri and c. apurensis will have darker bands of blackish colour that fades as they grow. Anyway google Wolfgang Ros to see his articles, good info...

[Viktor Jarikov]

It seems we never see any other species from that genus but apurensis, barring one case in a million.

I've kept 7 specimen from 7 different vendors worlds and years apart, hoping to see any different species but they all turned out to be apurensis.

I'd trust what Yellowcat is saying.

[amiidae]

Personally I dont think it is C apurensis. I have seen such cat fm imported time to time and they dont get large.

Do you have clearer side view photo of the mouth ? Fm my layman POV, C apurensis or C fowleri has underbite / lower jaw longer than upper.

[Viktor Jarikov]

That'd be intriguing... and the first time I would have heard about such a species.

I can't find juvi pictures of apurensis in Cat-eLog. I don't know if smaller fish exhibit the underbite. The underbite extent appears to vary too in larger fish. Perhaps a gender thing?

[yellowcat]

Amiidae makes an interesting observation about the lack of underbite, the pigmentation on the upper part of the dorsal fin may also be a clue? Agreed that a better profile photo would help too. If it's not c. apurensis then it would likely be a rare batrochoglanis species and won't get nearly as large an an apurensis. Just to muddy the waters here's a couple of photos of some batrochoglanis that I can't identify that closely resemble cephalosilurus..

[amiidae]

@Viktor,
Crappy shots I took more than 10yrs ago. This fish was abt 5inch TL. If you look carefully, you can see the underbite. Also, C apurensis is more compressed / flat and has wider mouth when you compared them at the same size.


@yellowcat,
Fm my observation:
Your top photos were taken at an angle, high level downward. Like most adult taking photos of young kids. hence, the fish in the photo looks rather compressed like C apurensis or C fowleri.

The 2nd photo I believe it was a photo taken by Edwin Tan aka Schmike.

I think both cats in the photos are the same sp as the cat in question.

[yellowcat]

I agree with amiidae that the fish is likely the same as the photo's, also knowing the upper photo is distorted as is another I found on the same fish. Amiidae has amazing photo skills by the way! Looking again at the original photo's of the new fish and the light tip of the dorsal fin, the banded colours on the maxillary barbels and a very slight hint of yellow banding on the back between the head and dorsal fin (a common trait in many batrochoglanis that varies with mood, lighting etc.), all point to it being a batrochoglanis sp. That said, Jarcave, you are quit fortunate as these are quite rare, (I've been hoping to find one like it or a similar species for years), If you still want a c. apurensis they're much easier to find, I know of two or three places here in the U.S. that have them right now. A look at the cat-elog photos under batrochoglanis you may see some distinguishing characteristics in common with your fish, in any case would like to see more pictures of yours. Batrochoglanis species haven't been fully studied and some are often misidentified or not identified at all and sometimes show up from places where they're not supposed to exist, making the genus more interesting to me anyway…
Another photo I found:

C.jpg (38.4 KiB) Viewed 5856 times

[grokefish]

I think it looks more likely a Batroglanis of some kind i looked for years in vain for one. I got this though Never managed to fully ID it

[Viktor Jarikov]

Mama mia! Look what the cats dragged in Seriously though, I am happy to see you Matt and happy to see you taking interest in this enigmatic Pseudopim.

[grokefish]

Hi Viktor