Spiders (Aranei) of the typical tundra subzone of the Yugorsky Peninsula, Russia

Abstract

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

Spiders (Aranei) of the Belyaka Spit, Chukotka: peculiarities of the fauna and biotopic distribution

“…The list of collected species is typical for araneofaunas of the northern part of Eurasian tundras. It is very similar to that of such well-studied Arctic regional faunas as Wrangel Island [Khruleva, 2007], the lower reaches of the Lena River [Tanasevitch, Nekhaeva, 2016], the northern Yamal [Tanasevitch, Rybalov, 2015], the Yugorsky Peninsula [Tanasevitch, Khruleva, 2017]. Usually, the species-lists contain at least 12-14 common species.…”

“…Preference of such stations is especially characteristic for Erigone arctica sibirica, Halorates holmgreni and H. spetsbergensis, the species, which form the core of the spider assemblages in the Belyaka Spit beaches. In other regions of the Arctic these species occur both on the sea coasts and in the interior, mainland regions, where they show very high abundance in some places in river floodplains, less often on gravelly slopes with sparse vegetation, see Khruleva [1987Khruleva [ , 1991, Khruleva & Berezin [2002], Tanasevitch & Rybalov [2015], Tanasevitch & Nekhaeva [2016], Tanasevitch & Khruleva [2017].…”

“…As mentioned above, the main feature of the spider distributions on the Belyaka Spit is restriction of most species to moist plots. Judging by the available data, in the Eurasian sector of the Arctic, i.e., arctic tundra subzone and the northern part of the typical tundra subzone, the core of araneocomplexes in wetlands contains about 20 purely arctic linyphiid species, see Khruleva [1987Khruleva [ , 1991 Khruleva [2017]. Based on our unpublished data, the list of species which are particularly specific for wetlands in the eastern part of the Asiatic tundra is as follows: Diplocephalus barbiger, Erigone psychrophila, Gibothorax tchernovi, Halorates holmgreni, Hilaira incondita L. Koch, 1879, H. nivalis Holm, 1937, H. proletaria, H.vexatrix, Hybauchenidium aquilonare, Masikia indistincta, Praestigia groenlandica Holm, 1967, Semljicola barbiger, S. simplex (Kulczyński, 1908, and Silometopoides pampia from Linyphiidae, and Pardosa septentrionalis (Westring, 1861), P. algens and (or) P. podhorskii (Kulczyński, 1907) from Lycosidae.…”

Latitudinal composition and spatial distribution of spiders (Aranei) in the vicinity of detached woodland (the Ary-Mas area, Taimyr)

“…As before [Tanasevitch, Khruleva, 2017], we used the division of all species into four latitudinal fractions. The Arctic fraction includes 21 species with an optimal distribution in lowland landscapes that lie to the north of the forest boundary.…”

“…Available data on these families from different tundra regions indicate significant variability in their composition (Table 4). They consist of spiders of "southern" faunal complexes (boreal and polyzonal), of which only Larinioides cornutus and Dictyna major have a clearly higher potential for colonization of the tundra [Tanasevitch, Koponen, 2007;Marusik et al, 2016;Tanasevitch, Nekhaeva, 2016;Tanasevitch, Khruleva, 2017]. Just these species form the basis of the spider population in the grass-undershrub layer in the Ary-Mas area.…”