If you held a gun to my head, I'd say a very young missgurnus fossilis.
Aside from that it looks like it could be a very obscure Niwaella or kuhli loach species.
Edit: Nevermind I got it! Pangio anguillaris! SO it is a kuhli loach of sorts!
Temp in the mid to high 70's, lots of places to hide, soft substrate like sand is strongly preferred. Should be kept in groups of at least 5. Relatively soft water. They'll accept most foods. Make sure to keep your water quality good since this particular species is almost certainly wild-caught. Maximum size of 4 inches but low bioload because of their shape. You're lucky, that's a really rare and neat find!
They should be fine with everything you have except for baby guppies and baby shrimp which they may eat.
Got a question about loaches? Ask me!
Loach count: 21
Baby fish count: 700+ (shelldwellers, gbr, angelfish)