Marusik Yu.M., Alfimov A.V. 2022. Unexpected diversity of wandering spiders (Aranei: Gnaphosidae, Philodromidae, Salticidae) of Northeastern Siberia // Arthropoda Selecta. Vol.31. No.4: 527–532 [in English].
ABSTRACT. It was found that diversity of spiders in Kolyma River delta (68.66°–69.25°N), located in the southern tundra, is about the same as in four other well studied local spider faunas located above the Polar Circle in boreal and tundra zones. But three families, Gnaphosidae, Philodromidae and Salticidae, have higher species diversity in the Kolyma River delta than in other local faunas of the boreal and tundra zones. To understand reasons for this phenomenon, we compared zoogeographical aspects of spiders from Northeastern Siberia and Finland and analyzed climate and microclimates indicators in five localities. Most likely the highest species diversity of named families in the tundra zone and even highest diversity among all local faunas lying north of Polar Circle can be explained by a combination of two major factors: history and microclimate. The Kolyma River delta was never covered by the ice shield like other compared areas; and its high climate continentality led to a higher heat supply of the soil surface in the warmest habitats.
KEY WORDS: Araneae, Western Chukotka, heat supply, microclimate, local fauna.