Tanasevitch A.V., Khruleva O.A. 2017. Spiders (Aranei) of the typical tundra subzone of the Yugorsky Peninsula, Russia // Arthropoda Selecta. Vol.26. No.4. P.341–368 [in English].
KEY WORDS: Russian Arctic, tundra, chorology, checklist, Amderma, Nenets A.O., habitat and stratification spreading.
ABSTRACT. An araneofauna of the vicinity of Amderma village in the northern part of the Yugorsky Peninsula, the subzone of typical tundra of the tundra zone, has been studied and analyzed. Some peculiarities of the spider fauna and population, as well as distributional patterns of species and chorological groups across the main zonal-landscape types of vegetation, have been established. The local fauna consists of 53 spider species in seven families, its taxonomic composition has oligotaxon pattern and can be described as Lin(85)-Lyc(4)-Tho(4). Compared to other local spider faunas of typical Eurasian tundras, the studied one differs in a lower proportion of Lycosidae. The linyphiid species Islandiana cristata Eskov, 1987 and Proislandiana pallida (Kulczy?ski, 1908) have been recorded from the European fauna for the first time. The studied araneofauna can be characterized as Siberian, with a great share of widespread species and a small proportion of European and East Palaearctic ones. A share of the arctic fraction (i.e., arctic, arcto-alpine and arcto-montane species) is 53%, that of hypoarctic elements (i.e., hypoarctic, hypoarctic-montane and hypoarctic-boreo-montane species) — 30%, the boreal and polyzonal fractions account for 8% and 9%, respectively. The diversity of spider assemblages of the main vegetation types are as follows: 48 species in intrazonal communities, 29 in anthropogenic,17 in zonal and 12 in azonal. Zonal tundras are distinct by a large share of the arctic fraction (76%), with boreal species being absent. A river valley is the source (or refugium) of “southern” elements, considerably increasing their share in the fauna of local tundras. Some of these species are restricted to the river valley only, although others can come out to the watershed and colonize its intrazonal and/or anthropogenic habitats. Species of the arctic fraction inhabit a wider range of tundra vegetation types, as compared to spiders of other fractions, but only a small their part is confined to zonal tundras. A large part of representatives of the arctic fraction is absent from zonal habitats and tend to occur in intrazonal biotopes of the watershed and/or river valley: viz., purely arctic species markedly prefer wet intrazonal habitats, whereas arcto-montane and arcto-alpine ones occur in the areas with gravelly soil. Species of the boreal fraction are absent from most habitats, congregating in wet intrazonal biotopes, the river valley and anthropogenic habitats. Most species and the vast majority of collected specimens were found in the ground (epigeal) layer. Only a few rare species were associated with the herbaceous layer: e.g., some abundant Semljicola species were recorded from there in certain days with favorable weather conditions. Embolic division of Erigone longipalpis (Sundevall, 1830) and E. tirolensis L. Koch, 1872 are illustrated.