The northern octocoral, paragorgia arborea (L.), in sub-antarctic waters

Abstract

SOME very interesting information has come to light during examination of the Discovery collections of octocorals concerning the supposed amphi-boreal alcyonarian Paragorgia arborea (L.). This species was considered an Atlantic boreal species (see Broch1) until Kinoshita2 and Hickson3 almost at the same time reported its presence on both sides of the northernmost Pacific. In the same period, Nutting4 identified a Paragorgia nodosa Kor. and Dan. from Hawaiian waters in 423-438 fathoms, where the bottom temperature was 41.0°F. (+ 5°C). A re-examination of Nutting's specimen by me has revealed that this species is identical with P. arborea. When discussing the zoogeographical features of this species 5, I characterized it as strictly boreal, but the record by Madsen6 of a specimen off the Portuguese coast (without biological and hydrographic data) raised doubts about this interpretation of its zoogeography. © 1957 Nature Publishing Group.