20. Bombus (Thoracobombus) filchnerae Vogt

(Figs 42, 43)

Bombus Filchnerae Vogt, 1908:100 .

Agrabombus adventor Skorikov, 1914:119. Bombus (Agrobombus) lii Tkalců, 1961:355 .

Material examined. 21 queens, 179 workers, 24 males (IAB).

Distribution in North China. Primarily on the edge of the northeast Qinghai-Tibetan plateau, the Liupanshan mountains, the Bashang plateau and the Hulunbeir grasslands. Common at medium elevations of the Qilianshan nature reserve in Gansu, at medium elevations of the Liupanshan nature reserve in southern Ningxia, at medium elevations of the loess plateau in eastern Gansu, and at low elevations of the Hulunbeir grasslands in northeastern Neimenggu. Rare at medium elevations of the Bashang plateau in northern Hebei, at medium elevations of the Taihangshan mountains in northern Shanxi, and at medium elevations of the sandy grasslands of the edge of the southern Neimenggu plateau. 44 localities (Fig. 42) between 602–2659 m (IAB).

Similar species in North China. This species is similar in its yellow colour pattern to some yellow B. amurensis, B. distinguendus, B. laesus and B. anachoreta (see the key; Figs 15, 19, 41, 43, 47).

Distribution in China. Hebei, Shanxi, Neimenggu, Gansu, Qinghai, Ningxia, Xinjiang (IAB).

Forage plants. ASTERACEAE: Cirsium leo, Helianthus annuus, Ligularia sagitta, Olgaea tangutica; FABACEAE: Medicago sativa, LAMIACEAE: Leonurus sibiricus, Salvia japonica .