Hillstream loach ID

[Eika]

Hi all,

Not been on this site for a while as I've been focussing on other types of fish, but ended up coming with 2 unidentified hillstream loaches yesterday and would appreciate any help.

There are 2 very flat ones that I've ID'd fairly confidently as Hypergastromyzon eubranchus, a big gastromyzon that I can't get any decent photos of yet, and a tiny little orange gastromyzon.

The smallest one is really intetesting me. Have only managed a blurry photo (will try to attach). It's just over 2cm long, quite dark with markings similar to gastromyzon ocellatus. But the caudal is clearly orange with no hint of red - and the dorsal is orange also, mostly along the top and bottom edges.There seems to be a hint of orange across the tail-end of the body too. And where the usual ocellated tail markings would be circular with spots within them, these are more like thin vertical bands with spots between.



Link to image in case attachment doesn't work- ->
https://imgur.com/a/VbL7E

I've never seen a hillstream with such a bold orange colouration, the best I can describe it is cadbury creme egg colour.

[ch.koenig]

Hi
That's G. contractus. In the last shipment there were different "unusual" species. Apart of H. humilis, G. lepidogaster and other not yet identified species.
https://picload.org/view/daodgllw/_csc2149.jpg.html
https://picload.org/view/daodglcr/_dsc1975.jpg.html
https://picload.org/view/daodglca/_dsc2111.jpg.html
https://picload.org/view/daodglcl/_dsc2166.jpg.html
and G. sp
https://picload.org/view/daodglci/_dsc2131.jpg.html
H. eubranchus: would be nice to see pics. Are you shure that's it's not H. humilis?
Cheers Charles
Edit for better understanding of my question: H. eubranchus is only recorded from Brunei. Fishing not allowed and no commercial fishing at all.
Have a look here
http://chuansong.me/n/358905051051

[ch.koenig]

from Sarawak of course. Syntopic with G. stellatus which is rare in shipments too.
Sorry, wrong notice in my archive. Thanks for the feed-back, Jim

[Eika]

Thank you so much Charles

G. contractus is a species I have never heard of before, and yes the pictures you share look identical to my little mystery loach, how exciting. I have noticed them suddenly in every pet shop where I live over the last month or 2, but until now have never seen them. It makes me wonder if wild stocks of the 'normal' species have depleted, forcing the collectors to use a new site. My little G contractus is doing well, and despite being skinny on arrival is gaining weight now in a heavily planted tropical tank (short term to help him gain condition, this tank has excellent biofilm and aufwachs). He is very fast and I still fail to get a clear picture of him.

The other gastromyzon is also doing well, it was the least skinny of them all on arrival and quickly took to grazing in the tank. He looks similar to the G contractus, only not showing orange in the dorsal. Do you think he is the same species? I have attached a link with the photo (he is the 4th photo).

The hypergastromyzon were most skinny on arrival and did not establish well. One passed away in the first week, to much heartbreak as we were very excited to take care of this species. The other one is doing a little better - he has been very inactive and not eating well up to this week, but is looking a little happier over the last couple of days and holding his caudal fin up with a bit more strength. He interacts with my tiny bristlenose pleco fry, and I feel it does him good to be a little territorial of his favourite spot. I'm hopeful he will improve. I've read that eubranchus have 5-6 cream body bars whereas humilis has 7-8, is this correct? Both of mine show 6 body bars. If they are indeed eubranchus then this is very interesting what you say regarding Brunei, I wonder if there is a way to report this finding internationally?

Here is a link to 3 photos of my Hypergastromyzon, followed by the larger Gastromyzon. Not great photos sorry, as my phone is rubbish!

https://imgur.com/a/kdhLz

Thanks again,
Erica

[ch.koenig]

Hi Erica
I presume you haven't read "Borneosuckers" by H.H. Tan? It's the refence for Borneo-hillies. Till now, no pic of living specimen existed of G. contractus . The identification is possible with the description in the book. Tan stated, that Roberts made notice of red/orange dorsal and caudal fin. The rest of the description matches with our species. Pattern e.g., but it is difficult to judge if you have no pics of the juvenile pattern that changes to adult pattern in the descriptions. Almost all Gastromyzon do change, some a lot e.g. G. lepidogaster which was in the shipment too.
There is still one species I couldn' identify. Wonder what it is.
The question if the appereance in a shipment could be due to a "shortage" of the common species in their habitat: nobody knows, even I can't get "hard" informations. I would guess No. It is normal that catchers try new rivers, when water is too high in the standard rivers. Makes, that some species won't appear in trade because the habitats are too far away od not easyly accessible.
It's Hpergastromyzon humilis. H.eubranchus would have been surprise. Not in regular chatching-aerea and the only pics I know.
H. humilis are delicate fish. The stress of the transition and the lack of food is too much for them. I have never seen more than a dozen in 400/500 shipment. Mostly none.
Brunei was my error, a wrong notice I made after reading the book.
If you want the description I would need a mail-adress.
Cheers Charles

[Jim Powers]

Very nice! I haven't been on here for awhile so I missed this thread.

[ch.koenig]

Hi Jim
Back from the asocial media?
" Erica: you are right with the numer of bars. All the pics I see of H. humilis show 7 bars. Could go to 8 when adult.
Cheers Charles