Zoological Journal of the Linnean Society, 2007, 149, 263–290. With 23 figures © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society, 2007, 149, 263–290 263 Blackwell Publishing LtdOxford, UKZOJZoological Journal of the Linnean Society0024-4082© 2007 The Linnean Society of London? 2007 149? 263290 Original Articles NEW FISSARCTURIDS FROM THE SOUTHERN OCEANA. BRANDT *E-mail: abrandt@zoologie.uni-hamburg.de Three new species of Fissarcturus (Isopoda, Antarcturidae) from the Southern Ocean ANGELIKA BRANDT* Zoological Museum, Martin-Luther-King-Platz 3, 20146 Hamburg, Germany Received July 2005; accepted for publication February 2006 Fissarcturus bathyweddellensis sp. nov. and Fissarcturus sandwichi sp. nov. are described from the abyssal Southern Ocean near the Antarctic Peninsula and Fissarcturus rossi sp. nov. is described from the shallow Ross Sea. A list of all described species of Fissarcturus is given. The new species differ from recognized species of the genus in the following respects: F. bathyweddellensis can be distinguished based on spination on the dorsum of the body, which is described in detail herein. It is most similar to F. emarginatus Brandt, 1990, but this has, for example, a shorter and less stout second cephalic spine. F. rossi can also be distinguished from F. bathyweddellensis based on spine pattern. Whereas all dorsal spines of F. bathyweddellensis are smooth, those of F. rossi are covered with spinules. F. sandwichi can be distinguished from the other species of the genus by the strong frontally bent supraoc- ular spines (females with second cephalic spines) and dorsal body surface, which is covered with flat, cauliflower-like elevations in submedial, lateral and coxal rows. © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society, 2007, 149, 263–290. ADDITIONAL KEYWORDS: deep sea – descriptions – taxonomy. INTRODUCTION The genus Fissarcturus was erected by Brandt, 1990 with the type species Fissarcturus emarginatus Brandt, 1990. During the Antarctic expeditions ANDEEP I-II (ANtarctic benthic DEEP-sea biodiversity: coloniza- tion history and recent community patterns) with RV Polarstern in 2002, specimens of two new species of Fissarcturus from the Southern Ocean deep sea were discovered, while during an earlier expedition of the New Zealand Oceanographic Institute to the Pennell Bank, Ross Sea shelf, Fissarcturus rossi sp. nov. was sampled. It was investigated at the National Institute for Water and Atmospheric Sciences (NIWA) in Octo- ber 2004. Descriptions of the new species will be presented herein together with a species and distribution list of the 16 recognized species of Fissarcturus (Table 1). It should be noted that one species group (species group A) of Fissarcturus possess the most proximal caudola- teral spines almost at the tip or at the tip of the ple- otelson. These are the type species, F. emarginatus Brandt, 1990, F. rugosus (Nordenstam, 1933), F. hirticornis (Monod, 1926), F. bathyweddellensis sp. nov., F. rossi sp. nov., F. stebbingnordenstami (Brandt, 1990), F. stephenseni Wägele, 1991 and F. poorei (Kussakin & Vasina, 1998a, b). Another species group (species group B) bears the lateral pleotelsonic spines at about midlength of pleotelson. To this group com- prises F. elongatus (Brandt, 1990), F. granulosus (Nor- denstam, 1933), F. patagonicus (Ohlin, 1901), F.minutus (Brandt, 1990), F. robustus (Brandt, 1990), F. scelerosus (Brandt, 1990), F. sandwichi sp. nov. and F. mawsoni (Hale, 1946). At this stage is difficult to present a phylogenetic analysis of these two species groups as only a few phylogenetically informative characters are known. METHODS Specimens were collected during the expeditions ANT XIX/3–4, ANDEEP I & II, in February and March 2002 from onboard the RV Polarstern in the Southern Ocean (Table 2). The collections were made by means Downloaded from https://academic.oup.com/zoolinnean/article/149/2/263/2627082 by guest on 26 November 2022