This article discusses radiocarbon dating results for soils and soil-like systems in the East Antarctic oases, including Schirmacher, Thala Hills, and Larsemann Hills. The organic matter of endolithic and hypolithic systems, soils of wind shelters, and soils under moss-algae vegetation were dated along with micro- and macroprofiles. Organic matter pools formed under extreme climatic conditions and originated not from vascular plants but from cryptogamic organisms, and photoautotrophic microbes have been identified within the oases of the East Antarctica. The organic matter of the most of East Antarctic soils is young and cannot reach a steady state because of the high dynamism in the soil cover due to active erosion. The oldest soil organic matter in East Antarctica was found in the soils formed in wind shelters and endolithic soil-like systems under the protection of consolidated rock surfaces. According to our data, the maximal duration for the formation of organic matter profiles within the oases of East Antarctica is ~500 yr, which is similar to the age determined for High Arctic soils in Eurasia. The absence of older soils, comparable with the Holocene deglaciation, can be due to the extreme conditions resulting in occasional catastrophic events that destroyed the soil organic horizons.

In the present paper, we examined the type material as well as newly collected specimens of the rare Antarctic eutardigrade species -Dastychius improvisus. Based on the available material, we prepared a full re-description of this species emending its description with new morphometrical characters. We conducted also phylogenetic analyses based on 18S and 28S rRNA sequence data and showed the position of the genus Dastychius in the family Isohypsibiidae. Moreover, we indicated that phylogenetic relationships within the superfamily Isohypsibioidea are still unresolved. This problem is mainly related to the relatively limited number of available sequences for the species from Isohypsibioidea and incorrectly identified sequences deposited in genetic databases, e.g. from the genus Eremobiotus. Finally, we also discussed the status of several members of Isohypsibioidea.

No abstract

Knowledge of the biodiversity of the Thala Hills oasis (Enderby Land, East Antarctica) is very limited. Here, we integrate all information available since 1962, when the Russian ‘Molodyozhnaya’ station was established in the western part of the oasis. The published data on local eukaryote diversity (lichens, embryophytes, metazoans) include records of 90 species. Since 2008, Belarusian Antarctic Expedition researchers have worked in the eastern part of the oasis, accessible from the Belarusian station ‘Vechernyaya Mount'. This research revealed 95 species, including 44 species not recorded in the earlier published literature. The level of available information is uneven across major taxa. Lichens are the better-known group, with 51 species recorded in total, including 13 species recently recorded for the first time in the oasis. New records were also obtained for rotifers. Thala Hills biodiversity is consistent with wider patterns of Antarctic biogeography, with a high proportion of regionally endemic species (especially metazoans), the occurrence of both endemic and bipolar species of lichens and generally low numbers of cosmopolitan species (largely limited to aquatic rotifers, with the caveat that up-to-date taxonomic studies are required). The lack of data on marine macrobenthos, soil nematodes and terrestrial rotifers emphasizes the need for studies focusing on these groups.