‘Putting names with faces’: a description ofEpiactis handisp. nov helps to resolve taxonomic confusion in species of the sea anemoneEpiactis(Actiniaria, Actiniidae)

Abstract

We resolve taxonomic confusion regarding brooding sea anemones in the genusEpiactisVerrill 1869a in the North Pacific Ocean based on newly collected material from Hokkaido (Japan), Haida Gwaii (British Columbia, Canada), and Kodiak and Adak Islands (Alaska, USA), and museum specimens collected from the Kurile Islands (Russia), Alaska, British Columbia, Oregon (USA), and California (USA). We find that the internally brooding individuals identified by Hand & Dunn (1974) asCnidopus ritteri(Torrey, 1902) and placed in the genusEpiactisby Fautin & Chia (1986) belong to a new species which we describe and nameEpiactis handisp. nov.Epiactis handiandE. ritterican be differentiated by morphological and behavioural features including ornamentation and structure of the column and mode of brooding offspring. To highlight and clarify these differences, we redescribeE. ritteribased on specimens from Alaska. We provide the first account of external brooding inE. ritteri, which necessitates a clarification of the differences betweenE. ritteriand another externally brooding species from the North Pacific,E. japonicaVerrill, 1869b.Epiactis ritteriandE. japonicadiffer in sex allocation, ornamentation of the column and details of external brooding: members ofE. ritteriare gonochoric with a smooth column and brood groove which tightly closes, whereas those ofE. japonicaare hermaphroditic and have mid-column spherules.