Henry H. C. Choong* and Dale R. Calder

Invertebrate Zoology Section, Department of Natural History, Royal Ontario Museum,100 Queen’s Park, Toronto, Ontario, Canada, M5S 2C6

*Corresponding author

Abstract

The leptothecate hydroid Sertularella mutsuensis Stechow, 1931 is reported on debris from the 2011 Japanese tsunami that came ashore on 5 June 2012 at Agate Beach north of Newport, Oregon. Its discovery on a barnacle (Semibalanus cariosus) from a derelict floating dock originating at Misawa, Honshu, confirms the capability of successful transoceanic dispersal for this species. We compare our specimens to Stechow’s syntype material of S. mutsuensis in collections at the Zoologische Staatssammlung München, and designate a lectotype and paralectotype of the species.

Key words: Leptothecata; hydroid; lectotype; transoceanic dispersal; anthropogenic debris; Oregon coast