Contributions to the aphid fauna (Hemiptera, Aphidoidea) of Chukotka Autonomous Okrug with descriptions of five new species Author Stekolshchikov, Andrey V. Author Khruleva, Olga A. text Zootaxa 2015 4044 1 1 44 journal article 10.11646/zootaxa.4044.1.1 2e3085b5-7005-4fef-a0c9-e351eb9fe798 1175-5326 289996 CB464055-EC76-4702-93B2-5BF1961F0A16 Euceraphis borealis Blackman in Blackman and De Boise, 2002 Material. 3 al., No. 10233, SSWBer, Betula nana exilis (Sukaczev) Hulten , 6.vii.2012 , on upper and lower surface of leaves; 2 al., No. 10265, SSWBer, Betula nana exilis (Sukaczev) Hulten , 26.vii.2012 , on lower surface of leaves; 3 al., No. 10271, SSWBer, Betula nana exilis (Sukaczev) Hulten , 2.viii.2012 , on lower surface of leaves. Distribution outside Chukotka AO . Finland , Canada (Quebec, Manitoba, North-west Territories), USA (Alaska). Comments. Specimens from Chukotka differ slightly in morphology from those described by Blackman and De Boise (2002) . Our specimens have a slightly shorter base of the 6th antennal segment—306–372 ( 320–390 in Blackman and De Boise), a greater range of the ratio of the 5th antennal segment to the base of the 6th antennal segment—2.09–2.79 ( 2.16–2.73 in Blackman and De Boise), a slightly lower ratio of the length of the 6th antennal segment to the length of the ultimate rostral segment—2.35–2.72 ( 2.38–3.05 in Blackman and De Boise), and slightly greater ratio of length of the ultimate rostral segment and the length of the 2nd segment of the hind tarsus— 0.60–0.65 ( 0.52–0.62 in Blackman and De Boise). However, these are minor differences and are probably the result of simple geographic variation.