Oh yes... Shooting some tiny flowers close up. On getting the prints back, what looks like a wide mouth lizard.... But it is still just rock.
If I find the print, I'll scan it sometime.
Wow, I had a very similar experience but I was shooing closeup in a trib of the Potomac River at Great Falls MD.
After printing/proofing a few choice frames I found as crayfish under a rock in the flow.