Some type of snail on my conch and hermit crab shell.

[samuel venner]

Hello fellow reefers.

I have just noticed that my conch has some weird snail or limpet critters attached to the backside of his shell.

A tongue comes out and picks at the sand and then retreats back into the shell when the conch moves.

does anyone know what they are ? If so are they safe to keep on the shell ?

I believe that they have been there for about 3 months but cant be sure.
Many thanks

 

[samuel venner]

From research it appears to be a horse hoof limpet ?