Hylaeus (Prosopis) confusus Nylander, 1852
Hylaeus confusus Nylander, 1852: 232, ♀, Ƌ (type locality: Europe); Dathe 1986a: 270.
Prosopis sublaevis Schenck, 1853: 215, ♀ (neotype—♀, designated by Straka & Bogusch 2011: 53, “Klánovický les –V, Praha- Klánovice” [Czech Republic]).
Hylaeus xanthocnemis Förster, 1871: 969, ♀ (neotype—♀, designated by Straka & Bogusch 2011: 53, “Klánovický les, Praha- Klánovice” [Czech Republic]).
Hylaeus nigriceps Förster, 1871: 977, ♀ (type locality: Aachen, Germany).
Hylaeus similatus Förster, 1871: 994 –995, Ƌ (type locality: Piesting, Austria).
Prosopis pallididens Dalla Torre, 1896: 28, nom. nov. for Hylaeus pallidens Curtis, 1831 .
Hylaeus monticola Bridwell, 1919: 155, ♀, Ƌ (type locality: Chuzenji, Tochigi Prefecture, Honshu, Japan).
Hylaeus wilmattae Cockerell, 1924a: 280 –281, ♀, Ƌ (type locality: Primorskiy Terr., Russia).
Material examined. Mongolia. Khovd Aimag: 1 ♂, 75 km E Altai, 1820 m, 20.VI.2012, AT (IBSS); Khuvsgul Aimag: 1 ♀, 17 km N Shine-Eder, Dund-Kholoi-Daba Pass, 1900 m, 22.VII.1975, EN (ZISP); Tuv Aimag: 1 ♂, 90 km N Ulaanbaatar, 1450 m, 6–8.VII.2003, JH (OLBL); Dornod Aimag: 1 ♂, 13 km W Dash-Balbar, Uldzy River, 24.VIII.1975, EN (ZISP); 1 ♂, 60 km ENE Bayan-Burda, Derkhin-Tsagan-Obo Mt., 3–4.VIII.1976, IK (ZISP).
Distribution in Mongolia. *Khovd Aimag, *Khuvsgul Aimag, Selenge Aimag, *Tuv Aimag, *Dornod Aimag (Fig. 4 f).
General distribution. Transpalaearctic up to Kuril Islands; Japan (Hokkaido, Honshu, Tsushima); China (Jilin, Xizang); all over Europe to 66° north, south to Greece; China (Xizang), Asia Minor, Caucasus.