(Figs 4 d, 5 a –b)
Hylaeus aborigensis Dathe 1994: 442, Ƥ, 3 (holotype— 3, “Sibirien, Pik Aborigen, 25 km SW Warmsteppe am Fluß Kolyma” [Magadan Prov., Russia], 500 m, 18.VII. 1992, leg. J. Bishop); Proshchalykin & Kupianskaya 2005: 5; Proshchalykin 2007 a: 881; 2007 b: 89; Quest 2009: 124; Proshchalykin & Quest 2009: 239; Ebmer 2011: 13.
Prosopis chasanensis Romankova in Osytshnjuk & Romankova 1995: 486, Ƥ, 3 (holotype— 3, Kraskino, Primorskiy Terr., Russia, 19.V. 1983, leg. A. Romankov [ZISP]); Davydova 2002: 94; Davydova & Pesenko 2002: 583; Proshchalykin 2003 b: 2; 2004: 3; 2005: 30; Ignatenko & Proshchalykin 2005: 244. Syn. nov.
Hylaeus chasanensis negoroi Ikudome 2004: 1 –5, Ƥ, 3 (holotype— 3, Tateyama, Toyama Pref., Honshu, Japan). Syn. nov.
Material examined: 33 Ƥ, 28 3. Russia: Tyva Republic (20 km NW Chadan, Khemchik Mt.); Yakutia (Labuiya River); Amurskaya Prov. (Skovorodino); Jewish AP (Birobidzhan, Ekaterino-Nikolskoe, 10 km N Dobroe); Primorskiy Terr. (Lazovskiy Nature Reserve, Shkotovo, Lazo, Kievka, 10 km SE Artem, Vityaz); Sakhalin (Sokol, 6 km E Shebunino); Kuril Islands (Kunashir: Yuzhno-Kurilsk); Magadan Prov. (Aborigen).
Distribution in Russia. Tyva Republic, Yakutia, Amurskaya Prov., Jewish AP, Primorskiy Terr., Sakhalin, Kuril Islands (Kunashir), Magadan Prov.
General distribution. Japan (Honshu), Asian part of Russia.
Remarks. Ikudome (2004) considers that the populations of the species on Honshu belong to a separate subspecies negoroi.