A thin and fragile, smooth glossy shell. White with black spiral lines. The animal is pink with a large frilly mantle with blue egdes. It can retract into the shell, but is quite slow in doing so. Size: 25mm
On intertidal rock flats & rock pools.
Hydatina physis is a sea slug species. This species is extremely widespread. It is found in tropical waters of the Atlantic, Pacific, and Indian oceans. Hdyatina physis grows to a length of up to 1.5 inches (3.8 cm.). The shell is thin and is partly covered by parapodia (fleshy flaps). The diet of Hydatina physis is very specialized; it feeds on polychaete worms. From January to May Hydatina physis is frequently found on shallow reef flats. It is most often seen at night.