TL;DR: Canonical correspondence analyses revealed that midge distributions were most strongly correlated with total Kjeldahl N, maximum lake depth, pH, and summer surface water temperature, suggesting that subfossil midges may provide valuable proxy evidence for paleoenvironmental conditions in the Beringian region of northwestern Canada and Alaska.
Abstract: Distributions of freshwater midges, including Chironomidae, Chaoboridae, and Ceratopogonidae, were analyzed along a transect of lakes extending north from Whitehorse (Yukon Territory) to the Arctic Ocean (Northwest Territories). Abiskomyia, Mesocricotopus, Monodiamesa, and Paracladius were restricted to arctic tundra lakes, whereas Chaoborus, Pseudochironomus, Polypedilum, and Glyptotendipes were clearly associated with forest and forest–tundra environments. Many other taxa were broadly distributed with little apparent regard to latitude or ecoclimatic region. Canonical correspondence analyses revealed that midge distributions were most strongly correlated with total Kjeldahl N, maximum lake depth, pH, and summer surface water temperature. The distribution patterns suggest that subfossil midges may provide valuable proxy evidence for paleoenvironmental conditions in the Beringian region of northwestern Canada and Alaska.
TL;DR: A systematic review of the genus Abiskomyia Edwards, 1937 is presented based on materials from the Russian Far East and bordering territories and three new species are described and figured.
Abstract: A systematic review of the genus Abiskomyia Edwards, 1937 is presented based on materials from the Russian Far East and bordering territories. Three new species: A. korbokhon sp. nov., A. levanidovi sp. nov., A. rivalis sp. nov. and one subspecies A. virgo orientalis subsp. nov. are described and figured. Emended generic diagnoses and keys to determination of adult males, pupae and fourth instar larvae of all known species and subspecies of the Abiskomyia of the Palaearctic region are provided.