A new species of Austrorhynchus (Platyhelminthes: Kalyptorhynchia) from King George Island (Maritime Antarctic)

Abstract

ABSTRACTA new species of the turbellarian genus Austrorhynchus (Kalyptorhynchia: Polycystididae) was found in King George Island (South Shetland Islands, Maritime Antarctic). The new species has eyes and white to greyish parenchyma. The type II prostate stylet has a funnel and a slightly bent tube with an inner stylet extending throughout its length; a strongly bent hook of about the same size as the tube is present. The type III prostate stylet has a foot and a style connected by a bridge, defining a broad window; the style expands to a comb-bearing plate with large teeth; the foot continues into a narrow flagellum with a distal expansion and a row of fine teeth. The species is oviparous. It can be distinguished from the other known Austrorhynchus species by the shape and size of the type II and type III prostate stylets. Out of the five known species of Austrorhynchus presenting a window in the type III stylet, the four more similar ones are found in the northern arm of the Scotia Arc and the Weddell Sea area. This is the first report of Kalyptorhynchia from the Antarctic portion of the Scotia Sea, and it confirms previous observations that the true number of Austrorhynchus species in the area must be higher than what is currently known.http://www.zoobank.org/urn:lsid:zoobank.org:pub:098ADF23-763B-41F6-A2F5-54F6AA8620E8