Tiny Fish Skeleton, Need Id'ing

hi! i work in a pet store, and while i was doing a water change in the so. african cichlid and plecostomus tank, i came across a very tiny skeleton, and i was wondering if anyone knew which it belonged to? i'm thinking pleco, but i'm probably wrong. 
 
i'm also hoping to preserve it, if anyone has any advice on that/knows if it can be done?
 
thanks in advance! here's some pictures!
 

Are you 100% sure it's dead? 

^^ LOL
 
My parents always tell me the story of how when i was little, i came accross the remains my cat had brought it and tearfully asked if it was still alive. It was a mouse's head LOL
 
That aside...
 
I dont see many skeletons of fish but plec skeletons generally look like plecs still! That would make me think more of another catfish, maybe a synodontis catfish was in the tank?

I'm thinking it's more likely to be one of the cichlids; plec skulls are broader and flatter and often have the first pectoral fin rays fused to them, AFAIK.
 
As long as you keep it dry ir should keep.