Bombus (Alpigenobombus) breviceps Smith, 1852

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 : 42-45

9. Bombus (Alpigenobombus) breviceps Smith, 1852

Figs 7–8 , 76‒93 , 114

Bombus nasutus Smith, 1852: 44 .

Bombus breviceps Smith. 1852: 44 . Note 1.

Bombus dentatus Handlirsch, 1888: 227 .

Bombus simulus Gribodo, 1892: 114 .

Bombus Channicus Gribodo. 1892: 116 .

Bombus laticeps Friese, 1905: 513 .

Bombus orichalceus Friese, 1916: 107 .

Bombus channicus var. [subsp.] brevigenalis Friese, 1918: 81 .

BOMBUS RUFOCOGNITUS Cockerell, 1922: 4 .

Bombus (Alpigenobombus) dentatus [subsp.] pretiosus Bischoff, 1936: 11 , not of Friese 1911a: 572 (= B. polaris Curtis ).

Bombus (Alpigenobombus) channicus [subsp.] cantonensis Bischoff, 1936: 14 .

Alpigenobombus breviceps [subsp.] coloricontrarius Tkalců, 1968: 14 .

Alpigenobombus breviceps [subsp.] colorilaetus Tkalců, 1968: 14 .

Alpigenobombus breviceps [subsp.] vicinus Tkalců, 1968: 21 .

Alpigenobombus breviceps [subsp.] bischoffiellus Tkalců, 1977: 224 . Replacement name for Bombus (Alpigenobombus) dentatus [subsp.] pretiosus Bischoff, 1936 .

Bombus rufocognitus var. [not subsp.] nefandus ‒ Cockerell 1931: 6, infrasubspecific.

Bremus (Alpigenobombus) dentatus var. [not subsp.] concinnus ‒ Frison 1935: 352, infrasubspecific.

Bremus (Alpigenobombus) dentatus var. [not subsp.] surdus ‒ Frison 1935: 353, infrasubspecific.

Bremus (Alpigenobombus) orichalceus var. [not subsp.] conjunctus ‒ Frison 1935: 355, infrasubspecific.

NOTE 1. Acceptance of B. breviceps as the valid name in preference to B. nasutus follows Tkalců (1968) as the First Reviser ( ICZN 1999: Article 24).

Species-taxon concept and variation

The taxon concept of the species B. breviceps 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. breviceps and B. genalis are separate species. The available COI-barcode-like sequences may all be low-divergence neonumts ( Fig. 11 ).

The PTP and morphological results ( Fig. 12 , keys) support and confirm the interpretation that the divergent colour patterns of the taxa breviceps s. str., channicus , and dentatus are conspecific as parts of the species B. breviceps ( Tkalců 1968; Williams et al. 2009; Hines & Williams 2012).

Variation in the colour-pattern diagrams of B. breviceps in Figs 76‒93 is arranged for the black-thorax Himalayan individuals approximately from west (Kashmir) to east ( Myanmar) and for the orange-banded Chinese and Southeast Asian individuals from north (Gansu) to south ( Thailand). Bombus breviceps , with the black-thorax colour pattern in the west (Himalaya) and centre (Hengduan) of its range (Figs 76‒80, 85‒89) and the orange-banded colour pattern in the south-east (Southeast Asia: Figs 81‒84, 90‒93), appears to mimic the abundant B. (Orientalibombus) haemorrhoidalis Smith, 1852 , and B. (Megabombus) montivagus Smith, 1878 ( Williams 2007: fig. 5h–i). The black-tailed colour patterns occur on the India / Myanmar border (Figs 80, 89) and in southern China (Figs 82‒83, 91‒92).

Type material

Bombus breviceps Smith, 1852: 44 . Holotype by monotypy: ♀ (worker) Zhejiang, China ( NHMUK). Examined .

Morphological diagnosis

Female

Wings very darkly clouded with brown with the veins dark brown, hair short, oculo-malar area shorter than broad, clypeus in its central area with many small punctures (cf. B. genalis , B. grahami ); hair of the thoracic dorsum black, often with orange bands anteriorly and posteriorly, hair of T1 yellow.

Male

Wings very darkly clouded with brown with the veins dark brown, hair short; genitalia ( Fig. 114 ) 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 narrowly pointed almost spine-like process, rounded in section (cf. B. genalis , B. grahami ).

Material sequenced in Fig. 12

BHUTAN • 1 ♀ (worker); Trashigang, Doksum ; 27.4377° N, 91.5833° E; 23 May 2017; W. Klein leg.; PW seq: NBC10098; RMNH: AG#149 .

CHINA • 1 ♁; Zhejiang, [Huangjiaotang]; 28.805° N, 120.961° E; GenBank seq: FJ175356; SC: AG#069 .

THAILAND • 1 ♀ (worker); Chiang Mai, Doi Inthanon ; 18.545° N, 98.516° E; 10 Aug. 2016; C. Sinpoo leg.; GenBank seq: MF582612; BEEP: AG#155 • 1 ♀ (worker); Chiang Mai, Doi Inthanon ; 18.554° N, 98.582° E; 19 Jul. 2016; C. Sinpoo leg.; GenBank seq: MF582613; BEEP: AG#156 .

Additional sequences in Fig. 10 and haplotype duplicates

CHINA • 1 ♀ (worker); Zhejiang, Gaolaoshan ; 28.9043° N, 120.5496° E; 4 Apr. 2021; Y. Chen leg.; CAU seq: TL01; CAU: AG#192 • 1 ♀ (worker); Gansu, Qingyugou ; 32.7734° N, 105.4137° E; 23 Jun. 2021; Y. Chen leg.; CAU seq: TL02; CAU: AG#193 • 1 ♀ (worker); Guangdong, Nanxiang ; 24.7677° N, 113.5932° E; 18 Jul. 2021; Y. Chen leg.; CAU seq: TL03; CAU: AG#194 • 1 ♀ (worker); Zhejiang, Pingding cun; 29.6615° N, 120.0088° E; 1 Oct. 2020; L. Tian leg.; CAU seq: TL04; CAU: AG#195 • 1 ♀ (worker); Hunan, Dazhushan ; 26.1662° N, 110.1746° E; 23 Jul. 2021; L. Tian leg.; CAU seq: TL05; CAU: AG#196 • 1 ♀ (worker); Hunan, Nanshan ; 26.1513° N, 110.1644° E; 22 Jul. 2021; L. Tian leg.; CAU seq: TL06; CAU: AG#197 • 1 ♀ (worker); Gansu, Liushuwan ; 33.0474° N, 105.2562° E; 21 Jun. 2021; Y. Chen leg.; CAU seq: TL07; CAU: AG#198 • 1 ♀ (worker); Guangdong, Nanxiang ; 24.7677° N, 113.5932° E; 18 Jul. 2021; Y. Chen leg.; CAU seq: TL08; CAU: AG#199 • same collection data as for preceding; GenBank seq: KP259094; IOZ: AG#152 • same collection data as for preceding; GenBank seq: MF478986; IAR: AG#153 • Ningxia; IAR seq: NX2; IAR: AG#093 .

INDIA • 1 ♀ (worker); Arunachal Pradesh, Jang ; 27.5821° N, 91.9704° E; 24 Sep. 2015; J. Neumayer leg.; NCBS BE653 seq: PWB6; NCBS: AG#041 .

THAILAND • 1 ♀; Chiang Mai, Doi Inthanon ; 18.5893° N, 98.4859° E; 21 Sep. 2006; Y. Areeluck leg.; BOLD seq: 3261H02; PCYU: AG#102 • 1 ♀ (worker); Chiang Mai, Doi Suthep ; 18.815° N, 98.4920° E; 26 Jun. 2016; C. Sinpoo leg.; GenBank seq: MF582617; BEEP: AG#157 • 2 ♀♀ (workers); Chiang Mai, Doi Inthanon ; 18.543° N, 98.548° E; 19 Jul. 2016; C. Sinpoo leg.; GenBank seq: MF582618, MF582619; BEEP: AG#158 , AG#159 • 1 ♀ (worker); Chiang Mai, Doi Inthanon ; 18.545° N, 98.516° E; 10 Aug. 2016; C. Sinpoo leg.; GenBank seq: MF582622; BEEP: AG#160 • 1 ♀ (worker); Chiang Mai, Doi Inthanon ; 18.5892° N, 98.48872° E; 21 Jul. 2015; N. Warrit et al. leg.; CT seq: CT540; CUNHM: AG#177 • 1 ♀ (worker); Chiang Mai, Doi Inthanon ; 18.5447° N, 98.5179° E; 21 Jul. 2015; N. Warrit et al. leg.; CT seq: CT552; CUNHM: AG#178 • 1 ♀ (worker); Chiang Mai, Khun Chang Khian ; 18.8387° N, 98.8965° E; 18 Jul. 2015; N. Warrit et al. leg.; CT seq: CT607; CUNHM: AG#179 • 1 ♀ (worker); Chiang Mai, Doi Kiew Lom ; 19.3175° N, 98.6006° E; 20 Nov. 2017; N. Warrit et al. leg.; CT seq: CT623; CUNHM: AG#180 • 1 ♀ (worker); Chiang Mai, Doi Ang Khang ; 19.8823° N, 99.0437° E; 21 Nov. 2017; N. Warrit et al. leg.; CT seq: CT625; CUNHM: AG#181 .

Global distribution

One of the most widespread Oriental species, in the Himalaya, Hengduan, Central and southern China, and Southeast Asia: India (Kashmir, Himachal Pradesh, Uttarakhand, Sikkim, Arunachal Pradesh), Nepal, Bhutan, China (Xizang, Yunnan, Sichuan, Gansu, Shaanxi, Chongqing, Hubei, Jiangxi, Hunan, Guizhou, Zhejiang, Fujian, Guangdong, Guangxi), Myanmar, Vietnam, Laos, Thailand: BEEP, CAU, CUNHM, IAR, IOZ, MCSN, NCBS, NHMUK, PCYU, PW, RMNH, SC, USNM, ZMHB.

This species is recorded at elevations of 484‒3000 m in the Himalaya ( Williams et al. 2010; Streinzer et al. 2019), and at 270‒3350 m in the Hengduan and in Shaanxi ( Williams et al. 2009; An et al. 2014). It is one of the few bumblebee species that occurs down to lower elevations in subtropical habitats, where it may be relatively common, even inside cities. However, in the warmer habitats it may be active only in the early morning and evening (Yunnan and Guangdong, PW pers. obs.; Thailand, C. Thanoosing pers. obs.).

Behaviour

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

Figures

Figs 1‒9. Individuals of the subgenus Alpigenobombus Skorikov, 1914 (with photo credits). 1. Bombus mastrucatus Gerstaecker, 1869, worker Norway robbing (P. Haringsma). 2. B. kashmirensis Friese, 1909 s. str., worker China-Sichuan robbing (PW). 3. B. kashmirensis (taxon meinertzhageni Richards, 1928) worker India-Kashmir-Zanskar (PW).4. B. sikkimiFriese, 1918, worker India-Arunachal (MS). 5. B. nobilis Friese, 1905 s. str., worker China-Yunnan (ZR). 6. B. genalis Friese, 1918, worker India-Arunachal (MS). 7. B. breviceps Smith, 1852 (taxon dentatus Handlirsch, 1888) worker China- Yunnan (PW). 8. B. breviceps (taxon channicus Gribodo, 1892) worker Thailand (CT). 9. B. grahami (Frison, 1933) worker India-Arunachal (MS). Some images reversed.

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.

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.