21. Bombus (Thoracobombus) impetuosus Smith

(Fig. 24)

BOMBUS IMPETUOSUS Smith, 1871:249, lectotype queen (Tkalců, 1987:61) BMNH examined. China: Yunnan.

Bombus Potanini Morawitz, 1890:350, type ZISP not found (Y. Pesenko, in litt.). Synonymised provisionally with Bombus impetuosus Smith by Williams (1998). China: ‘Kan-ssu’, probably Qinghai.

Bombus silvarum var. subrufescens Friese, 1913:87, holotype male MNHU examined. Synonymised with Megabombus potanini (Morawitz) by Tkalců (1987). China: ‘Tibet’,?Xizang.

Bombus (Agrobombus) yuennanensis Bischoff, 1936:14, lectotype queen (Tkalců, 1987:61) MNHU examined. Synonymised with Megabombus impetuosus (Smith) by Tkalců (1987). China: Yunnan.

Bombus (Agrobombus) combai Tkalců, 1961:357, type not seen. Synonymised with Megabombus potanini (Morawitz) by Tkalců (1987). China: Qinghai.

Material examined. 1 queen 97 workers 11 males (IAB).

Distribution in Gansu. Common at medium to high elevations of the Qinghai-Tibetan plateau in the southwest, rare at medium elevations of the western mountains (Fig. 24); 19 localities between 1719 and 3524 m (IAB).

Distribution in China. Chongqing, Sichuan, Yunnan, Gansu, Qinghai, Ningxia (IAB).

Forage plants. ASTERACEAE: Arctium lappa, Cirsium leo, Saussurea japonica, Saussurea sp., Senecio jacobaea, Sinacalia tangutica; BORAGINACEAE: Myosotis sylvatica; CAMPANULACEAE: Adenophora potaninii; FABACEAE: Astragalus bhotanensis, Melilotus officinalis, Oxytropis ochrocephala; GENTIANACEAE: Halenia elliptica; LAMIACEAE: Caryopteris incana, Dracocephalum heterophyllum, Nepeta prattii, Salvia przewalskii, Salvia sp., Thymus mongolicus; PAPAVERACEAE: Corydalis sp.; RANUNCULACEAE: Aconitum carmichaelii, A. gymnandrum, A. leucostomum, Clematis tangutica; SCROPHULARIACEAE: Euphrasia pectinata, Pedicularis kansuensis, P. spicata, Pedicularis sp.