Red-mouthed Frog Snail

Found in caves, beneath dead corals and under rocks, over coral and rocky reefs, shells often heavily encrusted. They have a warty surface that gives them their name of "Frog Shells"

Frog shells are often heavily encrusted.
Females are bigger than males.
When reproducing they lay long upright capsule like eggs which they sit on to protect until they hatch.