Sponges (Porifera: Demospongiae) recorded at the South Shetland Islands and near the Antarctic Peninsula during the Argentinian Summer Antarctic Expedition in 2012

Abstract

The Argentinian 2012 Summer Antarctic Expedition took place in the Austral summer of 2012. One of its main goals was the study of the benthic communities, considering the biodiversity and the distribution of the species around the Antarctic Peninsula and neighbouring islands. Samples were mainly collected by bottom trawling at eight locations. Sponges were sorted from total catch, photographed, labeled and frozen onboard, while identification was carried out using the classical methodology at the Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP, Argentina). In this preliminary study we provide data on sponges belonging to the Demospongiae Class. A total of 34 samples were collected and at least 24 species were identified. The most represented Order was Poecilosclerida with 18 species (Isodictya erinacea, I. lankesteri, I. cf. verrucosa, Mycale (Oxymycale) acerata, M. (M.) cf. tridens, Phorbas glaberrimus, P. acantochela, Lissodendoryx (Ectyodoryx) anacantha, L. (E.) ramilobosa, L. (L.) flabellata, Artemisina apollinis, Myxodoryx hanitschi, Clathria (Axosuberites) nidificata, Tedania charcoti, Iophon unicorne, I. cf. aceratum, Myxilla (M.) mollis, Kirkpatrickia aff. coulmani), followed by Haplosclerida with 5 species (Haliclonissa verrucosa, Haliclona sp., Calyx cf. arcuarius, Microxina charcoti, Hemigellius cf. pilosus). The most frequently recorded species was Mycale (O.) acerata followed by species of the genus Isodictya and Lissodendoryx. Some of the recorded species such as Phorbas glaberrimus, Myxodoryx hanitschi, Phorbas cf. acanthochela and Raspailia (Hymeraphiopsis) hentscheli have only scarce records in this region. The results of this study greatly contribute to the knowledge on the distribution and biodiversity of Antarctic sponges, a very important component of the benthic communities.