World-wide whale worms? A new species ofOsedaxfrom the shallow north Atlantic

Abstract

We describe a new species of the remarkable whalebone-eating siboglinid worm genus,Osedax, from a whale carcass in the shallow north Atlantic, west of Sweden. Previously only recorded from deep-sea (1500–3000 m) whale-falls in the northeast Pacific, this is the first species ofOsedaxknown from a shelf-depth whale-fall, and the first from the Atlantic Ocean. The new species,Osedax mucoflorissp. n., is abundant on the bones of an experimentally implanted Minke whale carcass (Balaenoptera acutorostrata) at 125 m depth in the shallow North Sea.O. mucofloriscan be cultured on bones maintained in aquaria. The presence ofO. mucoflorisin the shallow North Sea and northeast Pacific suggests global distribution on whale-falls for theOsedaxclade. Molecular evidence from mitochondrial cytochrome oxidase 1 (CO1) and 18S rRNA sequences suggests thatO. mucoflorishas high dispersal rates, and provides support for the idea of whale-falls acting as ‘stepping-stones’ for the global dispersal of siboglinid annelids over ecological and evolutionary time.