Bombus (Thoracobombus) laesus Morawitz

An, Jiandong, Huang, Jiaxing, Shao, Youquan, Zhang, Shiwen, Wang, Biao, Liu, Xinyu, Wu, Jie & Williams, Paul H., 2014, The bumblebees of North China (Apidae, Bombus Latreille), Zootaxa 3830 (1), pp. 1-89 : 33-34

19. Bombus (Thoracobombus) laesus Morawitz

( Figs 40, 41 )

Bombus laesus Morawitz, 1875:3 .

Bombus (Laesobombus) tianschanicus Panfilov, 1956:1327 .

Bombus (Laesobombus) maculidorsis Panfilov, 1956:1328 , by indication of Skorikov, 1922:23.

Taxonomy. For a discussion of the taxonomy of this species see Williams et al. (2009) and Williams (2011).

Material examined. 29 queens, 171 workers, 24 males (IAB).

Variation in North China. This species or species-complex shows strong variation in the colour pattern of the hair across its global distribution. In North China the principal variation is in the colour of the hair on the dorsum of the thorax, which may be orange-brown or yellow with a black band between the wing bases (see the key).

Similar species in North China. This species is very similar in its orange-brown colour pattern to B. muscorum , B. tricornis and B. atripes (see the key; Figs 41 , 45 , 69 , 71 ) and very similar in its colour pattern of yellow with a black band between the wing bases to B. amurensis , B. distinguendus , B. filchnerae and B. anachoreta (see the key; Figs 15 , 19 , 41 , 43 , 47 ).

Distribution in North China. Widely distributed on the edge of the east Qinghai-Tibetan plateau, the Liupanshan mountains, the edge of the southern Neimenggu plateau close to Shanxi and Hebei, and the grasslands of northeastern Neimenggu. Common at medium elevations of the Liupanshan mountains in southern Ningxia and eastern Gansu, at medium elevations of the Bashang plateau in northern Hebei, at medium elevations of the transition zone between the edge of east Otindag semi-desert and the southernmost of the Great Khingan mountains, in Majiayingzi, Keshiketeng, Neimenggu, and at low elevations of the Hulunbeir grasslands in northeastern Neimenggu. Rare at medium elevations of the Baihuashan nature reserve in Beijing, at medium to high elevations of edge of the east Qinghai-Tibetan plateau in Gansu, and at medium elevations of the Taihangshan mountains and the Lvliangshan mountains in Shanxi. 62 localities ( Fig. 40 ) between 215–3472 m (IAB).

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

Forage plants. ASTERACEAE : Cosmos bipinnatus , Helianthus annuus , Saussurea stella ; FABACEAE : Hedysarum gmelinii , Medicago sativa , Onobrychis viciifolia ; GENTIANACEAE : Gentiana sp.; LAMIACEAE : Caryopteris tangutica , Dracocephalum heterophyllum , Elsholtzia densa , E. fruticosa ; RANUNCULACEAE : Aconitum gymnandrum , Delphinium grandiflorum .

Figures

FIGURES 40 – 41. 40. Map showing the distribution of B. laesus in North China with records as black spots, the province boundaries in dark grey, and all sites with records of all bumblebee species in light grey. 41. B. laesus worker from Neimenggu.

FIGURES 44 – 45. 44. Map showing the distribution of B. muscorum in North China with records as black spots, the province boundaries in dark grey, and all sites with records of all bumblebee species in light grey. 45. B. muscorum worker visiting Onobrychis pulchella (Fabaceae) in Xinjiang.

FIGURES 68 – 69. 68. Map showing the distribution of B. tricornis in North China with record as black spot, the province boundaries in dark grey, and all sites with records of all bumblebee species in light grey. 69. B. tricornis queen from Beijing.

FIGURES 70 – 71. 70. Map showing the distribution of B. atripes in North China with records as black spots, the province boundaries in dark grey, and all sites with records of all bumblebee species in light grey. 71. B. atripes worker visiting Aralia chinensis (Araliaceae) in Shaanxi.

FIGURES 14 – 15. 14. Map showing the distribution of B. amurensis in North China with records as black spots, the province boundaries in dark grey, and all sites with records of all bumblebee species in light grey. 15. B. amurensis worker from Hebei.

FIGURES 18 – 19. 18. Map showing the distribution of B. distinguendus in North China with records as black spots, the province boundaries in dark grey, and all sites with records of all bumblebee species in light grey. 19. B. distinguendus worker form Neimenggu.

FIGURES 42 – 43. 42. Map showing the distribution of B. filchnerae in North China with records as black spots, the province boundaries in dark grey, and all sites with records of all bumblebee species in light grey. 43. B. filchnerae worker from Ningxia.

FIGURES 46 – 47. 46. Map showing the distribution of B. anachoreta in North China with records as black spots, the province boundaries in dark grey, and all sites with records of all bumblebee species in light grey. 47. B. anachoreta worker from Neimenggu.