6. Bombus (Alpigenobombus) nobilis Friese, 1905 s. str.

Figs 5, 61‒69, 111

Bombus nobilis Friese, 1905: 513 .

Bombus (Nobilibombus) xizangensis Wang, 1979: 188 .

Bombus (Nobilibombus) chayaensis Wang, 1979: 189 .

Species-taxon concept and variation

The taxon concept of the species B. nobilis here agrees with the recent interpretation (Williams 2022a) that it is separate from the taxon concept of the species B. sikkimi (see the comments above on B. sikkimi), 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. nobilis, B. sikkimi, and B. validus are separate species (Williams 2022a). The available COI-barcode-like sequences may all be low-divergence neonumts (Fig. 11).

From the morphology and colour pattern it appears likely that the yellow-banded holotype queen of the taxon chayaensis (Fig. 63, from Chagyab, north-eastern Xizang) and the white-banded holotype worker of the taxon xizangensis (Fig. 62, from Zayü, southern Xizang) are conspecific with B. nobilis . A small collection from northern Myanmar (Adung valley, 1931) of both yellow-banded (NHMUK: 3 ♀♀ (2 queens, 1 worker), Figs 65–66) and white-banded (NHMUK: 2 ♀♀ (workers), Fig. 61) individuals matches this species in morphology.

Variation of B. nobilis is shown in the colour-pattern diagrams in Figs 61‒69. Bombus nobilis, with the yellow-banded colour pattern in the north (northern Hengduan) of its range (Figs 63–64, 69), appears to mimic the abundant B. (Melanobombus) friseanus Skorikov, 1933 (Williams 2007: fig. 5j), whereas the white-and-yellow-banded colour pattern in the south (southern Hengduan: Figs 61–62, 67–68) appears to mimic the abundant B. (Ml.) prshewalskyi (Williams 2007: fig. 5p).

Type material

Bombus nobilis Friese, 1905: 513 .

Type not found, but identity not in doubt (Williams et al. 2009).

Bombus (Nobilibombus) xizangensis Wang, 1979: 188 .

Holotype by original designation: ♀ (worker) Zay ue, Xizang, China (IOZ). Examined .

Bombus (Nobilibombus) chayaensis Wang, 1979: 189 .

Holotype by original designation: ♀ (queen) Chagyab, Xizang, China (IOZ). Examined .

Morphological diagnosis

Female

Wings lightly clouded with brown with the veins dark brown, hair of medium length, oculo-malar area longer than broad, oculo-ocellar areas densely punctured with scattered medium-sized punctures with many small punctures between them, anterio-laterally to the lateral ocellus with large and small punctures sufficiently separated to have flat shining areas in between (cf. B. sikkimi, B. validus); hair on the anterior dorsum of the thorax and of the side of the thorax and scutellum either golden yellow or grey-white, on the scutellum the yellow hair anteriorly scarcely divided in the middle by a triangle of black, T1 yellow, T2 either predominantly black or with large anterior lateral patches yellow.

Male

Wings lightly clouded with brown with the veins dark brown, hair of medium length, oculo-malar area longer than broad; genitalia (Fig. 111) with the gonostylus short and distally near its midline axis deeply concavely rounded, its outer side about a half as long as its inner side with the two inner corners of the distal lobe rounded, the margin between them concave, penis-valve head weakly recurved, the recurved section about as long as broad at the base (cf. B. sikkimi, B. validus); hair on the anterior dorsum of the thorax and of the side of the thorax and scutellum either golden yellow or grey-white, T1 either yellow or if nearly white then T2 anterio-laterally also nearly white, on the scutellum in the middle the yellow only shallowly divided by black.

Material sequenced in Fig. 12

CHINA • 1 ♀ (worker); Yunnan, Lijiang; 27.0156° N, 100.1714° E; 12 Aug. 2017; H. Liang leg.; KIB seq: #2018064; KIB: AG#089 • 1 ♁; Xizang, Zhowagoin; 28.3469° N, 98.0102° E; 3 Sep. 2014; Q.-T. Wu leg.; IOZ seq: FPW30; IOZ: AG#187 • 1 ♀ (worker); Sichuan, Queershan; 29.5718° N, 98.1847° E; 5 Aug. 2018; Z. Ren et al. leg.; KIB seq: QESH201020; KIB: AG#143 • 1 ♀ (worker); Xizang, Dongdashan; 29.5718° N, 98.1847° E; 21 Jul. 2018; Z. Ren et al. leg.; KIB seq: DDSM202013; KIB: AG#087 • 1 ♁; Xizang, Zhowagoin; 28.3469° N, 98.0102° E; 2 Sep. 2014; Q.-T. Wu leg.; IOZ seq: FPW24; IOZ: AG#183 • Yunnan; IAR seq: HJF6; IAR: AG#090 .

Additional sequences in Fig. 10 and haplotype duplicates

CHINA • 1 ♀ (worker); Yunnan, Lijiang; 27.0156° N, 100.1714° E; 2 Sep. 2012; Y. Zhao leg.; KIB seq: #218628241; KIB: AG#108 • 1 ♀ (worker); Xizang, Zhowagoin; 28.3469° N, 98.0102° E; 3 Sep. 2014; Q.-T. Wu leg.; IOZ seq: FPW31; IOZ: AG#186 • 1 ♁; Xizang, Zhowagoin; 28.4853° N, 97.3634° E; 30 Aug. 2014; Q.-T. Wu leg.; IOZ seq: FPW29; IOZ: AG#188 • 1 ♀ (worker); same collection data as for preceding but 31 Aug. 2014; IOZ seq: FPW28; IOZ: AG#182 • 1 ♀ (worker); Xizang, Zhowagoin; 28.3469° N, 98.0102° E; 3 Sep. 2014; Q.-T. Wu leg.; IOZ seq: FPW26; IOZ: AG#189 • 1 ♀ (worker); same collection data as for preceding but 2 Sep. 2014; IOZ seq: FPW25; IOZ: AG#190 • 3 ♁♁; Xizang; 29.6114° N, 94.6441° E; 10 Aug. 2012; IAR seq: ZA3 ZA4 ZA5; IAR: AG#010 to AG#012 • 3 ♀♀ (workers); Xizang, Lulang; 29.6414° N, 94.6982° E; 26 Jul. 2018; Z. Ren et al. leg.; KIB seq: SJLSM108001, SJLSM104001, SJLSM104002; KIB: AG#086, AG#146, AG#147 • 1 ♀ (worker); Xizang, Galonglashan; 29.8219° N, 95.7110° E; 24 Jul. 2018; Z. Ren et al. leg.; KIB seq: GLLSL106001; KIB: AG#148 • 1 ♀ (worker); Yunnan, Lijiang; 27.0156° N, 100.1714° E; 12 Aug. 2017; H. Liang leg.; KIB seq: #2018063; KIB: AG#103 • 1 ♀ (worker); Xizang, Markam; 29.7432° N, 95.6753° E; 2 Sep. 2014; Q.-T. Wu leg.; IOZ seq: FPW32; IOZ: AG#191 .

Global distribution

Hengduan: China (Qinghai, Xizang, Yunnan, Sichuan, Gansu), Myanmar: IAR, IOZ, KIB, NHMUK, PW, SC, ZMHB.

This species is recorded at elevations of 2600‒4500 m in Sichuan, mostly above the tree line and into the subalpine zone (especially rich in Rhododendron species) (Williams et al. 2009).

Behaviour

Male eye not obviously enlarged relative to female eye: males are expected to show ‘patrolling’ behaviour in search of mates (Williams 1991).