Please ID this invert hitchhiker

[theop]

Please help ID this hitchhiker in a friend's tank. The creature is about 2" long on the long axis of the oval, is mobile, and is on the back glass in the pictures.

I think I know what it is, but won't say yet as to not bias your opinions.

 

[philter4]

It is a sunburst limpet, Lucapina aegis, very common here in south FL. Julian Sprung says they eat coral, but I've never had them eat anything but algae so I'm not sure. If you have it in a coral reef type tank I would be very cautious bucause I don't keep very many stony coral so maybe they do eat it.

 

[theop]

Thanks! I thought it was a keyhole limpet but didn't know the species.