8. Bombus (Alpigenobombus) genalis Friese, 1918

Figs 6, 74‒75, 113

Bombus genalis Friese, 1918: 84 .

Species-taxon concept and variation

The taxon concept of the species B. genalis here agrees with the long-standing interpretation (Williams 2022a) that it is separate from the taxon concepts of other species in the subgenus Alpigenobombus, based on: (1) our PTP analysis supports independent species-level coalescents in the COI gene (Fig. 12); corroborated by (2) diagnostic morphological character states (see the keys).

The PTP and morphological results (Fig. 12, keys) support the interpretation that B. genalis and B. breviceps are separate species. The available COI-barcode-like sequences may all be low-divergence neonumts (Fig. 11).

No substantial colour-pattern variation is known for B. genalis (Figs 74‒75). Bombus genalis, with its black with orange-legged colour pattern, appears to mimic the common B. (Pyrobombus) flavescens Smith, 1852, and B. (Melanobombus) eximius Smith, 1852 (Williams 2007: fig. 5a).

Type material

Bombus genalis Friese, 1918: 84 . Syntypes: ♀♀ (queen and worker) Sikkim, India (ZMHB). Examined .

Morphological diagnosis

Female

Wings pale yellow with the veins light orange (unique within the subgenus Alpigenobombus), hair short, oculo-malar area shorter than broad, clypeus in its central area shining with only a few small and large widely-spaced punctures (cf. B. breviceps); mid and hind tibiae exoskeleton and hair bright orange, hair of the thoracic dorsum and T1 black.

Male

Wings pale yellow with the veins light orange (unique within the subgenus Alpigenobombus), hair short, oculo-malar area shorter than broad; genitalia (Fig. 113) with the gonostylus nearly equally short on both its outer side and its inner side but with the distal lobe projecting inwards as a long broadly triangular acutely pointed process, triangular in section (cf. B. breviceps, B. grahami); mid and hind tibiae exoskeleton and hair bright orange, the hair of the scutellum and T1 predominantly black.

Material sequenced in Fig. 12

CHINA • 1 ♀ (worker); Xizang, Linzhi; 29.5710° N, 95.4633° E; 29 Aug. 2015; Q.-T. Wu leg.; IOZ seq: FPW12; IOZ: AG#184 .

Additional sequences in Fig. 10 and haplotype duplicates

CHINA • 1 ♀ (worker); Yunnan, Guanshizhai; 25.9334° N, 98.8008° E; 18 Aug. 2011; PW seq: PWB9; IAR: AG#040 • 1 ♀ (worker); Xizang, Miyuecun; 29.4065° N, 95.3721° E; 18 Aug. 2015; Q.-T. Wu leg.; IOZ seq: FPW13; IOZ: AG#185 .

INDIA • 2 ♀♀ (workers); Arunachal Pradesh, Salaya; 27.5969° N, 93.851° E; 22 Jun. 2018; J. Narah leg.; NCBS seq: BG463 BG471; NCBS: AG#200, AG#201 • 1 ♀ (worker); Arunachal Pradesh, Hari; 27.5838° N, 93.8446° E; 27 Sep. 2015; NCBS seq: BE637; NCBS: AG#202 .

Global distribution

Himalaya and borders of southern Hengduan: India (Sikkim, Arunachal Pradesh), China (Xizang, Yunnan), Myanmar: IAR, IOZ, NCBS, NHMUK, PW, ZMHB.

This is an uncommon species and few individuals have been recorded. This species is recorded at elevations of 1561‒1852 m in the Himalaya in the middle forest zone (Streinzer et al. 2019).

Behaviour

Male eye very slightly enlarged relative to female eye, male mate-searching behaviour unknown.