Life history of the Antarctic sea star Labidiaster annulatus (Asteroidea: Labidiasteridae) revealed by DNA barcoding

• Main Authors: Alexis M. Janosik, Andrew R. Mahon, Rudolf S. Scheltema, Kenneth M. Halanych
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2008
• Subjects: Antarctic; The Antarctic; Antarctic Peninsula; Kerguelen; Sandwich Islands; South Sandwich Islands; Bransfield Strait; Webb; Shag Rocks; Dearborn; Antarc*
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.421.3714; http://gump.auburn.edu/halanych/lab/Pub.pdfs/Janosik2008.pdf

(9–50) voracious Antarctic sea star with numerous large, conspicuous crossed pedicellariae. An active and opportunistic predator, it commonly preys upon euphausiids, amphipods, and small fish in the water column (Dearborn et al. 1991). Labidiaster annulatus is distributed around the Antarctic, Kerguelen, South Orkney, South Sandwich Islands, South Georgia, and Shag Rocks, at recorded depths of 30–440 m (Fisher 1940, unpublished data). Nothing is reported on the mode of reproduction in Labidiaster. Furthermore, the recognized family Labidiasteridae, composed of Labidiaster, Coronaster Rathbunaster, andPlazaster, is unlikely to be monophyletic, and the closest extant relative to Labidiaster remains unknown (Mah 2000, Foltz et al. 2007). In such a case larval identification by barcoding can be an important tool for examining life history (Webb et al. 2006). Here we use DNA barcoding techniques on partial mitochondrial 16S sequences, which serendipitously matched adults of L. annulatus to an unknown asteroid larvae collected along the western Antarctic Peninsula and Bransfield Strait region. Larvae and adult specimens were collected during two five week Antarctic voyages aboard the RV Laurence M. Gould from 23 November–22 December 2004 and 12 May–13 June 2006 (Table I). Larval specimens were collected using a conical 75 cm plankton net and with a 250 micron mesh towed for 20 min in a slow oblique decent to a depth of c. 180 m and then similarly returned to the surface. Benthic samples were collected using a Blake trawl, wire dredge, or epibenthic sled. Adult voucher specimens have been