Mystery Turbo Snail

Yesterday and today iv noticed some sort of turbo snail on the live rock in my tank, its quite small but the weird thing is iv only ever had one turbo snail in the tank, this was when i first set up the tank and the turbo snail i purchased was quite big, although i havnt seen the snail since i bought it back in October last year so for all i no the snail is probably dead
I dont know much about turbo snails at all but i'm sure they cant reproduce if theres only one snail in the tank.From what I see i'm sure its a mini turbo snail, I tried taken some pics but its hard to notice in the pictures iv taken. Any Ideas on what the heck it is ? How could it be a snail if there was only ever one in the tank, Iv quite afew hermits in the tank but it looks nothing like a crab at all.

Ill try take some decent pics, but in the mean time any ideas on what it could be ?

Thanks in Advance
Conor

 

Heres some pics:

 

prob just hitchhiked in on your rock

 

Right, it's not a Turbo, it's a Keyhole Limpet, probably a Diodora species. It shouldn't cause any problems.

Cheers,




Don