Distribution and biogeography of oribatid mites (Acari: Oribatida) in Antarctica, the sub-Antarctic islands and nearby land areas

• Main Authors: Stary, Josef, Block, William
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Taylor and Francis 1998
• Subjects: Antarctic; The Antarctic; Patagonia; New Zealand; Antarc*; Antarctica; Mite; Tierra del Fuego
• Online Access: http://nora.nerc.ac.uk/id/eprint/504985/; http://www.tandfonline.com/doi/abs/10.1080/00222939800770451?journalCode=tnah20#.UwxmtHmPNaQ

Oribatid mites are an ancient group of cosmopolitan terrestrial arthropods with limited trans-oceanic dispersal abilities. They provide an opportunity to answer questions concerning the role played by Gondwanaland, either as a migration route for terrestrial organisms or as a centre for their origin and subsequent glacial destruction, in the development of the biota of Antarctica, the sub-Antarctic islands and nearby land areas. Biogeographical studies of present-day oribatid mite faunas of the Antarctic region, New Zealand and South America (particularly the Andes Mountains) also allow insight into the historical development of such biota after the break-up of Gondwanaland. No records of fossil oribatid mites are known for the Antarctic and their main dispersal mechanisms within the biome are likely to be via sea-birds and possibly ocean currents. A total of 105 species from 20 families of oribatid mites are recorded from the Antarctic which, together with species records from South America, including Patagonia and Tierra del Fuego, and New Zealand, allowed faunal similarities to be examined using the similarity coefficient of Jaccard and principal co-ordinate analysis. Species endemism is high in both the continental (60%) and the sub-Antarctic zones (63%) compared with the maritime Antarctic zone (18%) and the Falkland Islands (19%), but lower than in the New Zealand fauna (83%) and in the Neotropical areas of South America (89%). Species diversity of oribatid mites in the Antarctic is low (five species in the continental Antarctic zone, 22 species recorded for the maritime Antarctic zone, and 78 species found in the sub-Antarctic zone) compared with New Zealand (330 species) and the Neotropical South American region (1193 species). The numerically-dominant species are from the families Oppiidae and Ameronothridae in the Antarctic region, but only a single endemic family (Maudheimiidae) occurs there. Several conclusions are drawn regarding the relationships of the oribatid mite faunas within Antarctica and ...