Common name : worm shells

Aspect : irregularly twisted tubular shell that grows in a worm-like, tangled manner; shell is cemented to hard surfaces (rocks, coral, other shells); corneous operculum; range from a few mm to over 20 cm; Usually white, gray, brown, or pinkish

Feeding : filtration of microorganisms in suspension (plankton), caught with sticky filaments that retract into the shell (unique among gastropods)

Environment : tropical to warm-temperate waters worldwide (Indo-Pacific (most diverse), Mediterranean, Caribbean, Eastern Pacific), rare in cold waters; in marine, intertidal to shallow subtidal depth on hard substrates (rocks, coral reefs, pier pilings, dead coral heads, mangrove roots)