7. Bombus (Alpigenobombus) validus Friese, 1905 stat. rev.

Figs 70‒73, 112

Bombus validus Friese, 1905: 510 .

Nobilibombus morawitziides Skorikov, 1933b: 62, by indication of Bombus haemorrhoidalis Morawitz, 1880: 344 (specifically the worker from ‘Gan-su’).

Bombus haemorrhoidalis ‒ Morawitz 1880: 344 (not of Smith, 1852: 43, misidentification = B. haemorrhoidalis Smith).

Alpigenobombus morawitziides ‒ Skorikov 1923: 159, published without description or indication, unavailable name.

Alpigenobombus morawitziides ‒ Skorikov 1931: 203, published without description or indication, unavailable name.

Bombus (Alpigenobombus) nobilis ‒ Williams et al. 2009: 170, (in part) misidentification.

Species-taxon concept and variation

The taxon concept of the species B. validus here agrees with the recent interpretation (Williams 2022a) that it is separate from the taxon concept of the species B. nobilis (see the comments above on B. nobilis), 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. validus, B. sikkimi, and B. nobilis are separate species (Williams 2022a).

Morawitz’s taxon haemorrhoidalis, with the oculo-malar area longer than for B. mastrucatus, matches closely with B. validus . The collection locality for one worker was given by Morawitz as ‘Gan-su’ (used in a much broader sense then than currently) and this individual was later referred to by Skorikov (1933b) is consistent with B. validus . It is intriguing that Skorikov (1933b) mentioned B. validus in his comments on morawitziides without giving any distinguishing characters. The other location for haemorrhoidalis given by Morawitz is ‘Ordoss’ (= Mu Su Shamo, referring to the Ordos desert, in Shaanxi), which is unexpected because it is at a much lower elevation and mostly more arid. This raises the possibility that Morawitz also had some rare paler individuals of the taxon beresovskii (not seen; but see the comments on B. grahami) in front of him, although this species has a shorter oculo-malar area that does not match Morawitz’s description, which is more likely to refer to B. (Melanobombus) pyrosoma Morawitz, 1890 .

Variation of B. validus is shown in the colour-pattern diagrams in Figs 65‒68. Bombus validus, with its black-thorax and largely-orange-metasoma colour pattern in northern Hengduan, appears to mimic the abundant B. (Melanobombus) pyrosoma (Williams 2007: close to fig. 5m).

Type material

Bombus validus Friese, 1905: 510 . Syntype (Tkalců 1987: 60): ♀ (queen) ‘ Turkestan Kashgar’, but probably Sichuan (ZMHB). Examined .

Morphological diagnosis

Female

Wings nearly clear with the veins dark brown, hair of medium length, oculo-malar area longer than broad, oculo-ocellar area sparsely punctured with few scattered medium-sized punctures with few small punctures between them with broad smooth areas (cf. B. sikkimi, B. nobilis); hair of the side of the thorax and scutellum predominantly black with only a few scattered grey hairs, T2‒3 with only a few black hairs along the midline.

Male

Wings nearly clear with the veins dark brown, hair of medium length, oculo-malar area longer than broad; genitalia (Fig. 112) with the gonostylus short and distally near its midline axis 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 nearly straight, penis-valve head weakly recurved, the recurved section about as long as broad at the base (cf. B. sikkimi, B. nobilis); hair of the side of the thorax and scutellum varying from predominantly black to predominantly grey-white, T2‒3 with only a few black hairs along the midline.

Material sequenced in Fig. 12

CHINA • 3 ♀♀ (workers); Gansu, Zhagana; 34.2477° N, 103.1329° E; 24 Jul. 2009; JH seq: PWB11, PWB14, PWB16; IAR: AG#039, 091, 092 .

Additional sequences in Fig. 10 and haplotype duplicates

CHINA • 1 ♁; Gansu, Shangbaimu Xia; 36.9620° N, 102.8209° E; 14 Aug 2011; JH seq: PWZA1; IAR: AG#008 .

Global distribution

Northern Hengduan: China (Sichuan, Gansu): IAR, IOZ, PW, ZIN, ZMHB.

This species has an unusually restricted distribution, recorded at elevations of 2196‒3524 m in Sichuan and Gansu, mostly above the tree line and into the subalpine zone (Williams et al. 2009; An et al. 2014).

Behaviour

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