Survey of species of Alto Mayo, San Martin, Peru

[bekateen]

Larsen, T.H., W. Palomino, H. Zeballos, P. Carrillo (eds.). 2024. Evaluación Biológica Rápida del Paisaje Alto Mayo, San Martin,
Perú. RAP Bulletin of Biological Assessment 73. Conservation International, Arlington, VA, USA.

https://www.conservation.org/press-rele ... rainforest
https://www.conservation.org/stories/ne ... odiversity

PDF: https://d2iwpl8k086uu2.cloudfront.net/d ... report.pdf

That first Chaetostoma looks just like

L336

(thanks go to Rob Oliver for pointing this out on FB)

[Shane]

[Among the shocking new fish discoveries was a ‘blob-headed’ fish (Chaetostoma sp. belonging to the bristlemouth armored catfishes), which has an enlarged blob-like head, a feature that the team’s fish scientists had never seen before.]

This seems a bit fishy in terms of academic rigor as the swelling of the rostrum in nuptial male Chaetostoma is well documented in both hobbyists and scientific literature. Their common name in English is rubbernose pleco for crying out loud.

No idea if the pictured fish is L336. The Rio Mayo is a tributary of the upper Huallaga and we have L336 listed as from the Rio Utcubamba.

-Shane

[bekateen]

This seems a bit fishy in terms of academic rigor as the swelling of the rostrum in nuptial male Chaetostoma is well documented in both hobbyists and scientific literature. Their common name in English is rubbernose pleco for crying out loud.

No idea if the pictured fish is L336. The Rio Mayo is a tributary of the upper Huallaga and we have L336 listed as from the Rio Utcubamba.

-Shane

As I read the publication, I felt like it was written as a press-release type of review for the public, not a scientific resource for investigators experienced with the fish.

As for the snout, I've seen mature male rubberlips of several species before and they had a fleshy growth, but it never seemed as pronounced as on this fish and as in the single photo of L336. Flavio Lima also stated it's L336. My question is this, is this fish any more "blobby" than other rubberlips? I thought it was.

Cheers, Eric

[Shane]

Having looked at the photo a lot on social media... I suspect the odd angle (it's a great photo) makes the rostrum look proportionately larger.
Agree it read more like a mainstream media release.
-Shane

[Jools]

Yeah, it's the lens all day long. Cool fish mind you!

Cheers,

Jools

[bekateen]

Interesting. And what about our photo of L336? That doesn't really have a typical forced perspective angle. Again, I've never seen any rubberlips with a rostum so enlarged.

[Jools]

Agreed, it is a cracker of an individual. I see a nuptial male in the Rio Mayo fish (elongated paired fins).

I'd be content calling it L336 as the rivers are close on a map, but I don't think we can because they are separated by mountains. If we were adding it to the site I'd be going for C. sp. `Rio Mayo`.

I've often been surprised how large hillstream

Chaetostoma

get. I wonder if it's a feature of mountain Chaetostoma that they get the largest rubbernoses either to protect eggs/fry by deflecting water current or perhaps it's just a "this rock is mine" mechanism. Either way, nuptial males are the easiest to collect.

Anyway, reckon the habitat drives the striking "rubbernose" feature.

Cheers,

Jools