Asterisks (*...*) surround words or phrases that are to be italicized.Anatomy and cnidae distinguish two species of deep-sea actinians that produce coiled, chitinous shells inhabited by hermit crabs of the genus *Parapagurus*. The actinian type species, *Stylobates aeneus*, first assigned to the Mollusca, occurs around Hawaii and Guam with *P. dofleini*. *Stylobates cancrisocia*, originally described as *Isadamsia cancrisocia*, occurs off east Africa with *P. trispinosus*