Sungai Setulang, Kalimantan Utara

[panaque]

Last month I got to go to Borneo again, to teach a field course. Lucky me!
We were here: 3°25'25.8"N 116°27'38.8"E (enter into google Earth to see location) in stunning prisitine primary rainforest. We caught many fish in the small river by our camp. The sungai Setulang is a tributary of the S. Malinau, which in turn flows into the S. Sesayap.
The S. Malinau:


The S. Setulang, where we did our fishing:



First up, by special request from @BomNya, Garra cf borneensis (or is this you newly described species?)

and again in situ...



Among the catfish were two species of

Glyptothorax

. The first I posted bad pictures of last year and @Silurus commented then that this species resembled an undescribed one from further south. Here are three specimens we found this year:
specimen 1



specimen 2



specimen 3

and again, after I returned it to the river...


The second Glyptothorax has a more slender body, uniform coloration and more but smaller cerations on the pectoral fin. Is this Glyptothorax platypogonides perhaps?

specimen 1




specimen 2



This will have to do for today, but many more to follow....

[Jools]

Awesome pics!

Jools

[panaque]

Awesome pics!

Thanks Jools! To restore karma, here are some bad ones.
The specimens in this post could be

Leiocassis micropogon

or indeed several species, based on body shape and colour pattern

Specimen 1, a bit too long for the photo tank...

Same specimen on video (turn on sound to get rainforest ambience)
http://vid1083.photobucket.com/albums/j ... 080172.mp4

Specimen 2. Smaller and stockier (head 25% of SL as opposed to 20% in specimen 1)



Specimen 3 (found in a local fisherman's catch, close to death - in fact, I think I had it for breakfast the next mornng)

[bekateen]

Except for the long fish that didn't fit well in your photo tank, otherwise, it looks like your photo tank worked well!

Cheers, Eric

[panaque]

I should say at this point that most of our students had no prior specific interest in fish. Like many zoology and conservation students, animals with four limbs were their primary interest. However, the diversity of fish really got them fascinated and converted many to the cause of the wet, slimey and/or warty. This specimen was a particular hit. It could be

Acrochordonichthys rugosus

, or, Acrochordonichthys melanogaster (the latter having been recorded from Sabah by Inger and Chin in THE FRESH-WATER FISHES OF NORTH BORNEO, 1962).

[panaque]

Except for the long fish that didn't fit well in your photo tank, otherwise, it looks like your photo tank worked well!

Cheers, Eric

Yes, it was definitely worth the effort.

[bekateen]

Wow, very nice.

Acrochordonichthys

and

Bunocephalus

- Convergent evolution will never cease to amaze me.

[Silurus]

I guess I am expected to weigh in on the identifications, so here goes...

First Glyptothorax: indeed unnamed

Second Glyptothorax: G. major - I had considered the possibility that this was another unnamed species, but ultimately could not find any significant differences between material from northeast Borneo and those from further west (closer to where this species was described).

Slender Leiocassis: L. tenebricus (specimens 1 and 3)

Stocky Leiocassis: L. collinus

Acrochrodonichthys: A. falcifer - this is based on locality more than anything else.

[Silurus]

Do you have high-res photos of those two Glyptothorax? The revision of Sundaic Glyptothorax that I am coauthoring is almost ready for submission, and it would be nice to have a few photos of live fishes (instead of a whole bunch of dead, preserved stuff).

[panaque]

Wow, very nice.

Acrochordonichthys

and

Bunocephalus

- Convergent evolution will never cease to amaze me.

The student who caught this in the cast net shook it out with so many other dead leaves. Luckily, one of our Indonesian students realised that one of the leaves was a fish!

On the subject of convergent evolution, the fish in the bottom left of the photo tank here (I'll come round to the others later) is Nematabramis everetti. Its dorsal and anal fins are positioned towards the rear, it has a sharply keeled belly, extended pectoral fins and an upturned mouth. If you found it in South America you would call it a hatched fish, but in fact it is a cyprinid. Larger specimens are more obviously hatchet-shaped but, it being the most common fish around, I never thought to take a decent picture of one!

[panaque]

I guess I am expected to weigh in on the identifications, so here goes...

First Glyptothorax: indeed unnamed

Second Glyptothorax: G. major - I had considered the possibility that this was another unnamed species, but ultimately could not find any significant differences between material from northeast Borneo and those from further west (closer to where this species was described).

Slender Leiocassis: L. tenebricus (specimens 1 and 3)

Stocky Leiocassis: L. collinus

Acrochrodonichthys: A. falcifer - this is based on locality more than anything else.

Many thanks! Yes please, weigh in on ID as much as you can. Your expertise is much appreciated.

[panaque]

Do you have high-res photos of those two Glyptothorax? The revision of Sundaic Glyptothorax that I am coauthoring is almost ready for submission, and it would be nice to have a few photos of live fishes (instead of a whole bunch of dead, preserved stuff).

Yes, I can get hi-res pictures. My photographer friend took these but I'm sure he'd be happy to share. I'll email or drop-box them as soon as I have them.

[Silurus]

On the subject of convergence, I find the similarity between Macrochirichthys macrochirus (cypriniform) and Rhaphiodon vulpinus (characiform) even more striking.

[panaque]

On the subject of convergence, I find the similarity between Macrochirichthys macrochirus (cypriniform) and Rhaphiodon vulpinus (characiform) even more striking.

Very nice example.

Hemibagrus fortis?



Mastacembelus sp.

Ompok siluroides

?

[racoll]

Fantastic fish and photos! The headshot of the Acrochordonichthys is great.

I like the spiny eel particularly. Any idea of the species?

[Silurus]

Hemibagrus fortis?

Looks like H. capitulum to me.

Mastacembelus sp.

This looks like Macrognathus keithi or a member of the M. maculatus species complex.

Ompok siluroides

?

I think this might be O. miostoma.

[panaque]

Fantastic fish and photos! The headshot of the Acrochordonichthys is great.

I like the spiny eel particularly. Any idea of the species?

Thanks! Silurius has answered your question...

[panaque]

Hemibagrus fortis?

Looks like H. capitulum to me.

Mastacembelus sp.

This looks like Macrognathus keithi or a member of the M. maculatus species complex.

Ompok siluroides

?

I think this might be O. miostoma.

Thanks for correcting me on all of these! Fish ID guide books for this part of the world are hard to come by. Your expert input is priceless.

[Silurus]

Fish ID guide books for this part of the world are hard to come by

Isn't there the book on the freshwater fishes of western Indonesia and Sulawesi by Kottelat et al. (1993)? That said, a (very much) revised edition is in the works (I think I am supposed to have a hand in it).

[panaque]

Isn't there the book on the freshwater fishes of western Indonesia and Sulawesi by Kottelat et al. (1993)? That said, a (very much) revised edition is in the works (I think I am supposed to have a hand in it).

I tried but failed so far to get hold of a copy of this book. I contacted Maurice Kottelat a while back and he mentioned he was working on the new version. I'll have to be patient...

[BomNya]

Panaque,

Thanks for posting those pics!!!! That Garra looks to be the real G. borneensis. The Caudal fin has strong black band on upper and lower rays, four transverse scale rows above lateral line, and it looks like the tip of the first branched dorsal ray would not pass the last branched ray when depressed (though it looks close).

Thank you!
Ryan

[panaque]

Panaque,

Thanks for posting those pics!!!! That Garra looks to be the real G. borneensis. The Caudal fin has strong black band on upper and lower rays, four transverse scale rows above lateral line, and it looks like the tip of the first branched dorsal ray would not pass the last branched ray when depressed (though it looks close).

Thank you!
Ryan

You're welcome! And thanks for the detailed explanation.

[BomNya]

Thank you! Now if only someone can get me a live photo of G. robertsi…

[Silurus]

After studying the pics of the second Glyptothorax closely, and comparing it with the images in my manuscript, I conclude that it is not G. major, but another unnamed (and to-be-named) species. I wish you had kept specimens, as I only have the putative holotype (and more is always better).

[panaque]

After studying the pics of the second Glyptothorax closely, and comparing it with the images in my manuscript, I conclude that it is not G. major, but another unnamed (and to-be-named) species. I wish you had kept specimens, as I only have the putative holotype (and more is always better).

I wish I could have kept specimens but I wouldn't want to do so without the required permits (acquiring these can be a time-consuming business in Indonesia and time is always in short supply). Maybe next time - this should be an annual trip for some time to come.

[panaque]

Some Rasbora next:
R. argyrotaenia (or similar...)


I don't have a name for this one


R. cf sumatrana


R. elegans

[panaque]

On to the Betta species...

This first was found in a small but relatively deep (80cm) pool in <1m wide stream that was mostly not more than a few cm deep. I believe it is B. ocellata

and a juvenile of the same


This 5cm specimen was caught in a shallow pool on the side of a 2m wide stream. I don't know the species - suggestions welcome!


This 14cm speciemen may be the same species or not. It was caught in a local fisherman's net in a deep (>2m) section of the main river

[panaque]

I was surprised to find this 20cm goby this far inland in the headwaters. But then again, what do I know? The first specimen regurtitated a semi-digested Rasbora after it was captured.
Locally it is known as "ikan pasir" which means sand-fish. Going by Inger and Chin (1962) I'd call it Glossogobius giuris but that doesn't seem right from what a bit of an internet search on that species throws up. Suggestions welcome, as ever.

[Silurus]

Most Glossogobius are practically impossible to identify to species from a photo. You'd need to see the sensory papilla patterns of the cheek lateralis system (best under a microscope) to do that.

[panaque]

Thanks Silurus. "Glossogobius sp." it is for now then.