Panaque nocturnus

[Erlend D Bertelsen]

Why isn't there any profile on Panaque/Panaqolus nocturnus Schaefer & Stewart, 1993 ?

I have some pictures of the fish, and I've had those for over 3 years now.

I did belive I had Panaque/Panaqolus sp. L-351, but today Nathan Lujan din ID them as Panaque/Panaqolus nocturnus

E

[Marc van Arc]

Why isn't there any profile on Panaque/Panaqolus nocturnus Schaefer & Stewart, 1993 ?

I have some pictures of the fish, and I've had those for over 3 years now.

I did believe I had Panaque/Panaqolus sp. L-351, but today Nathan Lujan did ID them as Panaque/Panaqolus nocturnus

Doesn't the "today" in your last line answer your own question?

[Erlend D Bertelsen]

Some pictures of the fish.

I did catch them myself outside Iquitos Peru in Rio Amazonas in 2008. I probably have a male and a female.

E

[Jools]

The question then, is

L351

= Panaque nocturnus?

Jools

[Erlend D Bertelsen]

I totally agree with you?

Alle the time I have kept this two, I have never been sure about the ID. I did believe it was L-351, because that was the specie that looked most like it.

I have also had some L-351, and seen plenty. They are not as dark, hey have a higher body, and more dark spots on the hole body.

E

[MatsP]

It would appear reasonable that Rio Huallaga has fish that also live in Rio Maranon - which the Rio Huallaga flows into...

Unfortunately, I don't have the description of P. nocturnus, so I can't check if any of the characters match/mismatch...

--
Mats

[racoll]

Unfortunately, I don't have the description of P. nocturnus

I think Milton (Suckermouth) would be your best bet. I imagine he would have, or could get hold of a copy.

[Suckermouth]

Unfortunately, I don't have the description of P. nocturnus

I think Milton (Suckermouth) would be your best bet. I imagine he would have, or could get hold of a copy.

I've been outed!

But seriously I have no idea. The description is appropriately descriptive, but there aren't really any characters that are used to diagnose P. nocturnus except for a lack of stripes or banding pattern found in other Panaque species, as well as differences in morphometrics from some species. In other words, it's diagnosed by its locality as well as a lack of other color patterns. A color pattern is described in the description but I don't think its comparable to what the live fish look like; even our preserved specimens of P. nocturnus differ from the holotype's described coloration.

So all in all I'm unsure. Nathan has actually seen live P. nocturnus, however, so he'd probably know right off the bat.

[Erlend D Bertelsen]

I agree that the scientific paper isn't helping so mutch.

From what Nathan wrote to me; I collected a large series of P. nocturnus from the type locality (just upstream of Iquitos on the Marañon) in 2006 and the individual you sent photos of falls well within the range of intraspecific variation I observed, so I'm pretty certain its P. nocturnus.

I have also added a picture of what I caught as Panaqolus sp. L-351. This fish is about the same size, but you can se the colure different, and also differesn in body shape.

I believe it was a reason why I chose to kept this two P.nocturus and not the other L-351.

E

[MatsP]

Erlend, are you saying you think there are two species: L351 and P. nocturnus, or just that you picked one of the prettier ones, and they are all one species?

--
Mats

[Erlend D Bertelsen]

My personal opinion is that they are two different species.

E

[racoll]

My personal opinion is that they are two different species.

Not sure I can see the difference. Can you be more specific?

Photos "in the tank" of similar sized fish would help, if you have any.

[Erlend D Bertelsen]

I base my opinion firstly on the different in colure, but also on body height. P. nocturnus is very jet-black in colour, with some dark spots on the back part of the fish. L-351 is not as dark, and has spots/markings all over the body. P. nocturnus is not as high as L-351. I have no idea if that is correct, just my opinion

I have no good photo of the fishes underwater. I have attached a photo of a smaller L-351 (the only I have) and a bigger P. nocturnus.

E

[racoll]

P. nocturnus is very jet-black in colour, with some dark spots on the back part of the fish. L-351 is not as dark, and has spots/markings all over the body. P. nocturnus is not as high as L-351. I have no idea if that is correct, just my opinion

Okay, makes sense. Must say I've not seen enough of these "in the flesh" to offer much more of an opinion. This difference in colour pattern and shape is apparent even when mature at adult size?

What I have noticed though, when checking DATZ, is that L350 is probably more likely to be P. nocturnus than

Hemiancistrus pankimpuju

. L350 is clearly is a better match to your P. nocturnus as identified by Nathan Lujan.

[Erlend D Bertelsen]

I really doubt its L-350 i have. That is a very special looking fish, they are as fare as I know also white inside the mouth.
Attached is a picture of a Hemiancistrus pankimpuju L-350. But all of these 3 fishes are close looking.

E

[racoll]

I really doubt its L-350 i have. That is a very special looking fish, they are as fare as I know also white inside the mouth.
Attached is a picture of a Hemiancistrus pankimpuju L-350.

Hi Erlend, I'm not sure you understood what I was saying. I'll be clearer this time:

L350 is not Hemiancistrus pankimpuju. L350 is Panaque nocturnus.

[that's at least how I see it.]

[Erlend D Bertelsen]

Hi Racoll.

Ok I see. But I have to say I don't agree with you.

Hemiancistrus pankimpuju and L-350 match perfectly.

Panaque nocturnus have no L-nummer
L-351 Panaqolus sp. have no scientific description
L-350 is described as Hemiancistrus pankimpuju

E

[racoll]

Hemiancistrus pankimpuju and L-350 match perfectly.

Really? Take another look at the photo in DATZ. Hemiancistrus pankimpuju is a jet black or white fish. The photo of L350 shows a brown fish with black spots - in fact identical to your P. nocturnus.

[racoll]

So, here's a photo of the DATZ L350 "iconotype" linked from l-welse.com.

http://www.l-welse.com/reviewpost/showf ... =350bg.jpg.

[Jools]

Hemiancistrus pankimpuju and L-350 match perfectly.

Really? Take another look at the photo in DATZ. Hemiancistrus pankimpuju is a jet black or white fish. The photo of L350 shows a brown fish with black spots - in fact identical to your P. nocturnus.

Erlend,

A photo of the mouth of your fish might help here?

Jools

[Erlend D Bertelsen]

Attracted is a picture of the mouth. This show typical Panaque/Panaqolus teeth. Sorry, but this is the best picture I have.

The photo linked to as L-350 in DATZ, must be wrong. I would say L-351.

My personal conclusion so fare is:

L-351. More brownish in color with spots all over and a higher body compared with P. nocturnus
P. nocturnus More black in color, mostly spots on the backer part of the body. Has no L-number.
L-350 is jet-black or white. Some time you can se white markings where the fins are attached, see photo over.

I will also trust Nathan Lujan in this case, espesily when he also was the author of Hemiancistrus pankimpuju L-350. But I may of corse be wrong, and if that is the case, it would be that L-351 and P. nocturnus is the same specie.

E

[racoll]

The photo linked to as L-350 in DATZ, must be wrong.

This isn't the way the system works. It's the other way round, we are wrong, not the photo!

The original DATZ photo fixes the identity of the proposed new species or variety as a published L number, much in the same way as the holotype of an officially described species.

The fact that everyone has been calling what we now call H. pankimpuju, L350, should not matter!

As I see it H. pankimpuju does not have an L number, L350 is P. nocturnus, and L351 would then be P. cf. nocturnus, if these proposed morphological differences stack up.

[Borbi]

Hi Racoll,

As I see it H. pankimpuju does not have an L number, L350 is P. nocturnus, and L351 would then be P. cf. nocturnus, if these proposed morphological differences stack up.

..but "the fish formerly known as L 350" has a non-Panaque (or Panaqolus) dentition. Teeth are more abundant and two-tipped.
Just like H. pankimpuju reportedly has. And there is also the lack of an iris operculum, which is present neither in H. pankimpuju nor L 350, but is present in L 351.
With respect to L 351 I would like to remark that pictures of most fish one finds tend to be of juvenile or semiadult specimen, while all adult specimen I have seen yet tend to appear almost completely black. That is no conclusive evidence of course, but a thing that should be kept in mind.

Cheers, Sandor

[racoll]

..but "the fish formerly known as L 350" has a non-Panaque (or Panaqolus) dentition. Teeth are more abundant and two-tipped.
Just like H. pankimpuju reportedly has. And there is also the lack of an iris operculum, which is present neither in H. pankimpuju nor L 350, but is present in L 351.

I am not quite sure what you are saying here Sandor. Can you elaborate slightly?

[Acanthicus]

As I see it H. pankimpuju does not have an L number, L350 is P. nocturnus, and L351 would then be P. cf. nocturnus, if these proposed morphological differences stack up.

..but "the fish formerly known as L 350" has a non-Panaque (or Panaqolus) dentition. Teeth are more abundant and two-tipped.
Just like H. pankimpuju reportedly has. And there is also the lack of an iris operculum, which is present neither in H. pankimpuju nor L 350, but is present in L 351.

L 350 can´t be P. nocturnus because the dentition doesn´t fit with the typical Panaqolus/Panaque dentition . But it fits with H. pankimpuju. Furthermore L 351 can´t stand in such a close relation to P. nocturnus (if you suggest this one to be L 350), because the dentition is different and there is an iris opreculum in L 351, but not in L 350.

[Borbi]

Hi Racoll,

sorry for the confusing post.
Daniel (hopefully) put it more understandably.

My main point was, that L 351 cannot be Hemiancistrus pankimpuju because L 351 has the typical dentition of Panaque/Panaqolus, while H. pankimpuju has more numerous, two-tipped teeth.
This same type of two-tipped dentition (as well as the lack of an iris operculum) is, however, found in L 350, which among other resemblances lets me believe that L 350 is in fact H. pankimpuju.

Regarding the (non-)identity of L 351 and P. nocturnus I am not yet fully convinced. The fact that L 351 is not P. nocturnus but closely related is here based on their differing coloration and slightly different body shapes.
The point that leaves me undecided on that subject is that most pictures of L 351 are of small(ish) specimen. I do know, however, that adult L 351 turn almost completely black, too. Therefore, a comparison of Erlends P. nocturnus with some L 351 of the same size would be more telling, IMHO. This also holds true for body proportions, comparing juveniles with adults is not necessarily adequate.

Hope that clarifies my point a bit..

Cheers, Sandor

[racoll]

L 350 can´t be P. nocturnus because the dentition doesn´t fit with the typical Panaqolus/Panaque dentition

My main point was, that L 351 cannot be Hemiancistrus pankimpuju because L 351 has the typical dentition of Panaque/Panaqolus, while H. pankimpuju has more numerous, two-tipped teeth.
This same type of two-tipped dentition (as well as the lack of an iris operculum) is, however, found in L 350, which among other resemblances lets me believe that L 350 is in fact H. pankimpuju.

Thanks for the clarifications, but I don't think I am explaining my point very well yet.

You are talking about the fish we call L350 (below), not the fish in the original photo of L350 in DATZ.

So, I agree that this fish is H. pankimpuju, and that we call it L350:



We may have been calling it L350 for a long time, but the original photo of L350 in DATZ is not of this species.

Am I making any sense?

[Jools]

I see your point Rupert. Also, for me, the eye diameter is much smaller than in Erlend's fish.

I wonder if Erlend's fish might be

L329

and indeed that is P. nocturnus. I note that's where I've put it in the past.

Jools

[MatsP]

If that is the case, can we see the difference between the fish in this discussion and the one in the pictures by Erlend on the L329 data-sheet? I'm just curious as to what the difference is...

--
Mats

[racoll]

Yikes, now this is getting confusing!