Stylobates birtlesi sp. n. a new species of carcinoecium-forming sea anemone (Cnidaria Actiniaria Actiniidae) from eastern Australia

摘要

We describe a new species of carcinoecium-forming sea anemone, Stylobates birtlesi >sp. n., from sites 590–964 m deep in the Coral Sea, off the coast of Queensland, Australia. An anemone of this genus settles on a gastropod shell inhabited by a hermit crab, then covers and extends the shell to produce a chitinous structure termed a carcinoecium. Stylobates birtlesi >sp. n. is symbiotic with the hermit crab Sympagurus trispinosus (Balss, 1911). The nature of marginal sphincter muscle and nematocyst size and distribution distinguish Stylobates birtlesi >sp. n. from other species in the genus. The four known species of Stylobates are allopatric, each inhabiting a separate ocean basin of the Indo-West Pacific. We also extend the known range of Stylobates loisetteae in the Indian Ocean off the coast of Western Australia.