Bombus (Alpigenobombus) validus Friese, 1905

Williams, Paul H., An, Jiandong, Dorji, Phurpa, Huang, Jiaxing, Jaffar, Saleem, Japoshvili, George, Narah, Jaya, Ren, Zongxin, Streinzer, Martin, Thanoosing, Chawatat, Tian, Li & Orr, Michael C., 2023, Bumblebees with big teeth: revising the subgenus Alpigenobombus with the good, the bad and the ugly of numts (Hymenoptera: Apidae), European Journal of Taxonomy 892 (1), pp. 1-65 : 40-41

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).

Figures

Figs 19–105 (see pages 28–29). Simplified diagrams for the colour patterns of the hair on the dorsum for particular female (f) and male (m) specimens of the species from Fig. 12. The dorsum is divided into regions, each of which shows only the predominant or most apparent colour for that region, using a simplified colour palette, with olive indicating a mixture of black and yellow hair, and grey indicating a mixture of black and white hair.

Figs 106–115. Morphology of the male genitalia for species of the subgenus Alpigenobombus Skorikov, 1914, from the dorsal aspect, anterior at the bottom of the image, posterior at the top. 106. Bombus wurflenii Radoszkowski, 1860, Turkey. 107. B mastrucatus Gerstaecker, 1869, Austria. 108. B. kashmirensis Friese, 1909, India-Kashmir. 109. B. rainai Williams, 2022, India-Kashmir. 110. B. sikkimi Friese, 1918, Nepal. 111. B. nobilis Friese, 1905, China-Sichuan. 112. B. validus Friese, 1905, China-Gansu. 113. B. genalis Friese, 1918, China-Yunnan. 114. B. breviceps Smith, 1852, ChinaSichuan. 115. B. grahami (Frison, 1933) China-Sichuan (left penis-valve recurved hook missing). Scale bars = 1 mm.

Fig. 12. Interpretation of filtered MrBayes estimate of phylogeny as a metric tree (outgroup B. festivus Smith, 1861, not shown) for the subgenus Alpigenobombus Skorikov, 1914, from COI-like sequences from the sequences identified in black and orange in Fig. 11 together with Bayesian Poisson-tree-process (PTP) models re-applied for assessing support for species’ gene coalescents by maximum likelihood (for the 11 most likely candidate species). The scale bar is calibrated in substitutions per nucleotide site. Sequence labels and branch colours as in Fig. 10. Numbers above nodes are the Bayesian support values that all daughter haplotypes are parts of a single species. Grey spots show likely mitochondrial-to-nuclear transfers of the low-divergence numts accepted for estimating this tree. Asterisks mark sequences used as informal proxies for the type specimens of each of the taxon names in Table 2. To the right in grey are shown the interpretations of the PTP results as candidate species using the oldest available names for the species.

Fig. 10. Default interpretation of MrBayes estimate of phylogeny as a metric tree (outgroup B. festivus Smith, 1861, not shown) for the subgenus Alpigenobombus Skorikov, 1914, from COI-like sequences from GenBank and BOLD databases with additions from the authors, analysed with Bayesian Poissontree-process (PTP) models for assessing support for species’ gene coalescents by maximum likelihood (PTP scores are shown above branches: scores approaching 1, and where branches change from blue to red, indicates where the most likely species’ gene coalescents are identified for 17 candidate species). The scale bar is calibrated in substitutions per nucleotide site. Each sequence is labelled with: sequence length; a morphological taxon name; a code consisting of a sequence identifier from the project database and a specimen identifier from the online database; its country and (for larger countries) state or province of origin.