This paper presents the first records of the brittle star Ophiactis abyssicola in Canadian waters and range extensions of up to 1900 km in the Northwest Atlantic from previously known locations. Samples were collected off northern Labrador and the northern portion of insular Newfoundland (eastern Canada) at 433 and 1097 m depths, respectively. This newly recorded species of brittle star from the bathyal zone off Newfoundland and Labrador adds to the marine biodiversity of Canada and to the general distribution knowledge of O. abyssicola.

The genus Astrodia (Echinodermata: Ophiuroidea: Asteronychidae) was revised based on 34 specimens including two syntypes of Asteronyx excavata, two syntypes of Asteronyx plana and two syntypes of Ophiocreas abyssicola. We proposed a transfer of Ophiocreas abyssicola (Euryalidae) to the genus Astrodia. Consequently, Astrodia now includes four species, Astrodia abyssicola, A. excavata, A. plana and A. tenuispina. These four species are all redescribed. A taxonomic key to the species of the genus Astrodia is also provided.

Ophiuroids are a conspicuous and often dominant component of the Antarctic continental shelf benthos. Here we report on the ophiuroids collected from the Burdwood Bank, off the Patagonian Shelf, through the shallow water areas of the Scotia Arc, down the west Antarctic Peninsula and as far south as Pine Island Bay in the eastern Amundsen Sea. This preliminary and primarily pattern based study identifies some regional differences in assemblages and highlights the role of the Antarctic Circumpolar Current as a barrier, as well as a facilitator, to dispersal. In order to effectively compare between studies we highlight the need for accurate, expert taxonomic identification of specimens.