Bombus (Alpigenobombus) rainai Williams, 2022

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 : 35-36

4. Bombus (Alpigenobombus) rainai Williams, 2022

Figs 49‒53 , 109

Bombus (Alpigenobombus) rainai Williams, 2022a: 132 .

Bombus (Alpigenobombus) kashmirensis ‒ Williams 1991: 66, (in part) misidentification.

Species-taxon concept and variation

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

This taxon was discussed as divergent from B. kashmirensis by Williams (1991: 68‒69, figs 308‒310), although it was not then named as a separate species.

Although the PTP and morphological results ( Fig. 12 , keys) support the interpretation that B. rainai and B. kashmirensis are separate species (Williams 2022a), the available COI-barcode-like sequences may all be low-divergence neonumts ( Fig. 11 ).

Variation of B. rainai is shown in the colour-pattern diagrams in Figs 49‒53. Bombus rainai , with its white-banded red-tailed colour pattern in the Himalaya, appears to mimic the abundant B. (Sibiricobombus) longiceps Smith, 1878 (until recently regarded as part of B. asiaticus Morawitz, 1875 ), and similar species ( Williams 2007: fig. 5l).

Type material

Bombus (Alpigenobombus) rainai Williams 2022a: 132 . Holotype by original designation: ♀ (queen) Kashmir , India ( ZSC). Examined .

Morphological diagnosis

Female

Wings nearly clear with veins dark brown, hair medium length, oculo-malar area shorter than broad, clypeus adjacent to the labrum slightly raised in the centre so that the transverse anterior groove is interrupted, this central area with few small punctures and more shining than the surrounding areas, oculo-ocellar area in its outer half with only a few small shallow punctures, any larger punctures confined to the eye margin (cf. B. kashmirensis ); hair of the side of the thorax in no more than its upper third white and the scutellum predominantly black, hair of T5 entirely orange without obviously paler tips.

Male

Wings nearly clear with veins dark brown, hair medium length, oculo-malar area shorter than broad; genitalia ( Fig. 109 ) with the gonostylus long and distally near its midline axis convexly rounded, length on its outer side about a quarter as long as on its inner side with the two inner corners of the distal lobe rounded, the margin between them convex, penis-valve head strongly recurved, the recurved hook much longer than broad and narrow, tapering gradually to the apex (cf. B. kashmirensis ); male eye distinctly enlarged relative to female eye; hair of the side of the thorax with black and white intermixed, but often predominantly black in its lower half, hair of the sides of T5‒6 orange, hair of T3 often predominantly orange.

Material sequenced in Fig. 12

INDIA • 1 ♀ (queen); Kashmir , Achoora; 34.636° N, 74.864° E; 26 Jun. 2009; R. Raina leg.; BOLD seq: 1552E01; ZSC: AG#080 • 1 ♀ (queen); Kashmir , Apharwat; 34.055° N, 74.386° E; 21 Aug. 2009; R. Raina leg.; BOLD seq: 1552D12; ZSC: AG#081 .

Global distribution

Western Himalaya: Pakistan, India (Kashmir): NHMUK, PW, ZSC.

This species is recorded at elevations of 2542‒4200 m, primarily above the tree line and high into the alpine zone ( Williams 1991).

Behaviour

Male eye distinctly enlarged relative to female eye: males are expected to show ‘cruising’ behaviour when searching for mates in Kashmir ( 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. 11. Re-interpretation of sequences from Fig. 10, re-drawn with the percentage of nucleotides A and T at codon position 3 (AT3%) for each sequence given after the sequence label. Sequences are classified: (a) in purple – earlier-diverging groups of sequences without unique morphology that often have lower AT3% and shorter sequences that appear to duplicate species as pseudospecies in Fig. 10 – these sequences are interpreted as older, more divergent numts; (b) red – remaining sequences with low AT3% (<95%) – these are interpreted as younger, less divergent numts; (c) orange – sequences from the red group but with the highest AT3% available for some taxa, selected to retain these taxa in the analysis; (d) grey and brown – sequences that are duplicate haplotypes for the black and orange sequences above and often shorter; (e) black – likely orthologous sequences with high AT3% (≥ 95%) and unique haplotypes.