Bombus (Alpigenobombus), Skorikov, 1914

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 : 20-26

Subgenus Alpigenobombus Skorikov, 1914

= Mastrucatobombus Krueger, 1917 .

= Nobilibombus Richards, 1968 .

We associate a total of 83 published formal names with species of the subgenus Alpigenobombus (including misspellings and infrasubspecific names). Applying the ICZN (1999) rules for an assessment of the status of these names under Article 45.6, just 55 names are considered to be available (most unavailable names are not listed here, but are in a database, PW in prep.). Below is a list of the 11 species recognised from the integrative analysis together with the synonyms that occur most frequently in the literature (identified from morphology) with the changes since the last checklist ( Williams 1998). There are few novel arrangements of the names here because there have been so many different re-arrangements in the past, although our results show the currently supported interpretation.

The subgenus Mastrucatobombus Krueger, 1917 is a synonym of Alpigenobombus . The subgenus Nobilibombus Richards, 1968 has been included within the subgenus Alpigenobombus ( Williams et al. 2008) , based on evidence from the five genes obtained by Cameron et al. (2007). The name Nobilibombus was published initially without fixation of a type species ( Skorikov 1933b), or as a junior synonym ( Bischoff 1936; Milliron 1961), so the first valid publication is by Richards (1968). The species of Nobilibombus are recognised here as the nobilis -group of species.

wurflenii -group

Bombus wurflenii Radoszkowski, 1860 s. str.

= alpigenus Morawitz, 1874

= uralicus ( Tkalců, 1969)

Bombus mastrucatus Gerstaecker, 1869 stat. rev.

= brevigena Thomson, 1870

= flavicante Pérez, 1890

= pyrenaicus Vogt, 1909

= collaris Friese, 1909

= transitorius Friese, 1909

= lutescens Friese, 1909

= luteus Friese, 1909

= tirolensis Friese, 1911

= apfelbecki Reinig in Reinig & Rasmont, 1988

= knechteli Reinig in Reinig & Rasmont, 1988

= balcaniensis Rasmont, Ghisbain & Terzo, 2021

kashmirensis -group

Bombus kashmirensis Friese, 1909

= stramineus Friese, 1909

= tetrachromus Cockerell, 1909

= pulcherrimus ( Skorikov, 1914)

= meinertzhageni Richards, 1928

Bombus rainai Williams, 2022

nobilis -group

Bombus sikkimi Friese, 1918 stat. rev.

Bombus nobilis Friese, 1905 s. str.

= xizangensis Wang, 1979

= chayaensis Wang, 1979

Bombus validus Friese, 1905 stat. rev.

= morawitziides (Skorikov, 1933)

breviceps -group

Bombus genalis Friese, 1918

Bombus breviceps Smith, 1852 s. lat.

= nasutus Smith, 1852

= dentatus Handlirsch, 1888

= simulus Gribodo, 1892

= channicus Gribodo, 1892

= laticeps Friese, 1905

= orichalceus Friese, 1916

= brevigenalis Friese, 1918

= rufocognitus Cockerell, 1922

= pretiosus Bischoff, 1936

= cantonensis Bischoff, 1936

= coloricontrarius Tkalců, 1968

= colorilaetus Tkalců, 1968

= vicinus Tkalců, 1968

= bischoffiellus Tkalců, 1977

Bombus grahami ( Frison, 1933) s. lat.

= beresovskii (Skorikov, 1933) syn. nov.

= melani Wang & Yao, 1993 syn. nov.

Bombus angustus Chiu, 1948

Key to species for females of the subgenus Alpigenobombus

Future identification of species of the subgenus Alpigenobombus will be most reliable for specimens from which COI-barcode-like data are available for comparison of nucleotide differences with the reference data we provide in supplementary data. Keys using morphological shape, surface sculpturing, and hair-colour-pattern characters follow below. Our results imply that in some cases we should be able to assign most reliably the specimens with locality labels to groups or species on the basis of their collection locality alone. All identifications of species from the key or from the figures should be checked against the species’ diagnoses within the accounts for each species.

Diagrams showing the major aspects of variation in the colour-patterns of the dorsal hair are presented in Figs 19‒105. These diagrams summarise only the major differences ( Williams 2007) rather than finer details (e.g., Williams 1991: figs 295‒310). This is a simplification to aid quantitative comparisons and inevitably requires compromises. Colour-pattern variation within species is established with reference to particular individuals identified from COI barcodes for each diagram. Morphology of the male genitalia is illustrated in Figs 106‒115.

1. Oculo-malar area (= malar area) shorter than broad (OM length measured as the minimum distance between the eye ventrally and concave margin between the mandibular condyles (hinges); OM breadth measured as the distance between and including the mandibular condyles) ....................... 2

– Oculo-malar area longer than broad ................................................................................................. 9

2. Clypeus adjacent to the labrum not raised in the centre but flat so that the transverse anterior groove is not interrupted, this central area uniformly with many small punctures and not shining (Europe, Turkey, Caucasus, Urals) .................................................................................................................. 3

– 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 (Asia east of Pakistan) ...................................................................................................................... 4

3. Ocello-ocular area (= ocellocular area) with the punctures anterior to the unpunctured area (adjacent to the lateral ocellus and between it and towards the inner ocular margin) less dense than posterior to it; hair of the thoracic dorsum either entirely black or sometimes with bands anteriorly and posteriorly yellow (Figs 26‒30) (Europe, in Scandinavia, Pyrenees, Alps, Carpathians, Greece) ..... ........................................................................................ B. mastrucatus Gerstaecker, 1869 stat. rev.

– Ocello-ocular area with the punctures anterior to the unpunctured area at least as dense as posterior to it; hair of the thoracic dorsum black with bands anteriorly and usually posteriorly white (Figs 19‒22) ( Turkey, Caucasus, Urals) .................................................... B. wurflenii Radoszkowski, 1860 s. str.

4. Wings either clear or very lightly clouded with brown, T1-2 with hair predominantly (nearly completely) either white or yellow (occurring at elevations above 3000 m) ................................... 5

– Wings either darkly clouded with brown or if pale yellow or nearly clear then T1-2 with hair black (occurring at elevations below 3000 m) ........................................................................................... 6

5. Oculo-ocellar area in its outer half with large and medium punctures; hair of T5 orange with white tips, the side of the thorax in at least its upper half and the scutellum either white or yellow (Figs 35‒41) (Himalaya, Hengduan) ................................................... B. kashmirensis Friese, 1909

– Oculo-ocellar area in its outer half with only a few small shallow punctures, any larger punctures confined to the eye margin; hair of T5 entirely orange without paler tips, the side of the thorax in no more than its upper third white and the scutellum predominantly black (Figs 49‒51) (Kashmir) ..... ..................................................................................................................... B. rainai Williams, 2022

6. Wings very darkly clouded with brown, hair of T1 either yellow or grey or white ......................... 7

– Wings either pale yellow or nearly clear, hair of T1 black .............................................................. 8

7. Clypeus in its central area with many small punctures, many spaced by only their own widths; hair of the thoracic dorsum black, often with orange bands anteriorly and posteriorly, T1 yellow (Figs 76‒84) ................................................................................................ B. breviceps Smith, 1852

– Clypeus in its central area with only a few large and small punctures, most spaced by more than their own widths; hair of the thoracic dorsum black, either usually with many grey hairs intermixed so as to appear silvery olive-grey, with the majority of the hair along the longitudinal midline white, or if entirely black then T1 predominantly grey-white (Figs 94‒100) ............. B. grahami ( Frison, 1933)

8. Mid and hind tibiae with exoskeleton and hair bright orange; wings pale yellow with the veins orange; clypeus in its central area with widely-scattered large punctures and only a few micropunctures that are more widely-spaced than their own widths (Fig. 74) (Himalaya) ......................... ........................................................................................................................ B. genalis Friese, 1918

– Mid and hind tibiae with the exoskeleton and hair predominantly black; wings nearly clear with the veins black; clypeus in its central area with widely-scattered large punctures and many small punctures that are as widely spaced as their own widths (Fig. 104) (Taiwan) ................................... ....................................................................................................................... B. angustus Chiu, 1948

9. Oculo-ocellar area sparsely punctured with few scattered medium-sized punctures with few small punctures between them with broad smooth areas; hair of the side of the thorax and scutellum predominantly black, T2–3 with only a few black hairs along the midline (Figs 70‒71) (Sichuan, Gansu) .............................................................................................. B. validus Friese, 1905 stat. rev.

– Oculo-ocellar areas densely punctured with scattered medium-sized punctures with many small punctures between them and lacking smooth areas; hair of the side of the thorax and scutellum predominantly either grey or yellow, T2–3 usually with a few black hairs along the midline and a transverse band of black hairs (Himalaya, Hengduan) ................................................................... 10

10. Oculo-ocellar area anterio-lateral to the lateral ocellus with large and small punctures sufficiently separated to have flat shining areas in between (= interspaces) (at least for queens, differences weaker for workers); 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 incompletely divided in the middle by black, T1 yellow, T2 either predominantly black or with anterior lateral patches yellow (Figs 61‒66) (Hengduan) .................................................................... B. nobilis Friese, 1905

– Oculo-ocellar area anterio-lateral to the lateral ocellus with large, medium and many small punctures almost coalescing and without flat shining areas in between (= interspaces) (at least for queens, differences weaker for workers); hair on the anterior dorsum of the thorax and of the side of the thorax and scutellum and T1 either grey or olive-yellow, on the scutellum the pale hair anteriorly often deeply divided in the middle by a triangle of black, T2 either predominantly yellow or with large anterior lateral patches yellow (Figs 54‒57) (Himalaya) ....... B. sikkimi Friese, 1918 stat. rev.

Key to species for males of the subgenus Alpigenobombus

1. Oculo-malar area shorter than broad (OM length measured as the minimum distance between the eye ventrally and concave margin between the mandibular condyles (hinges); OM breadth measured as the distance between and including the mandibular condyles); genitalia with the gonocoxa with the distal (posterior) inner corner not projecting inwards ( Figs 106‒109, 113‒115 ) ....................... 2

– Oculo-malar area longer than broad; genitalia with the gonocoxa with the distal (posterior) inner corner projecting strongly inwards ( Figs 110‒112 ) .......................................................................... 9

2. From the region including European, Turkish, Caucasus and Ural mountains ................................ 3

– From the region including the mountains of Asia east of Pakistan.................................................. 4

3. Hair of the thoracic dorsum between the wing bases predominantly black, usually with few or no yellow hairs (Figs 31‒34) (Europe, especially in Scandinavia, Pyrenees, Alps, Carpathians, Greece) ........................................................................... B. mastrucatus Gerstaecker, 1869 stat. rev.

– Hair of the thoracic dorsum between the wing bases either predominantly yellow or with many yellow hairs (Figs 23‒25) ( Turkey, Caucasus, Urals) .......... B. wurflenii Radoszkowski, 1860 s. str.

4. Genitalia with the penis valve distally recurved as a sickle by more than 90° with the hook much longer than broad ( Figs 108‒109 ) (occurring at elevations above 3000 m) ..................................... 5

– Genitalia with the penis valve distally recurved as a sickle by just 90° with the hook scarcely longer than broad ( Figs 113‒115 ) (occurring at elevations below 3000 m) ................................................ 6

5. Hair of the side of T5‒6 orange at the base but white-tipped, T3 predominantly black, the side of the thorax either yellow or white, the pale hair reaching to the midleg bases (Figs 42‒48); genitalia with the penis valve recurved head broad, the recurved section narrowing only just before the tip, gonostylus on its outer side less than half as long as on its inner side ( Fig. 108 ) (Himalaya including Kashmir, Hengduan) ............................................................................ B. kashmirensis Friese, 1909

– Hair of the side of T5‒6 orange, T3 predominantly orange, the side of the thorax with black and white intermixed, but often predominantly black in its lower half (Figs 52‒53); genitalia with the penis valve recurved head narrow, the recurved section tapering gradually to the tip, gonostylus on its outer side about half as long as on its inner side ( Fig. 109 ) (Kashmir) ......................................... ..................................................................................................................... B. rainai Williams, 2022

6. Wings very darkly clouded with brown (Figs 85‒93) ................................ B. breviceps Smith, 1852

– Wings either pale yellow or nearly clear .......................................................................................... 7

7. Hair of the thoracic dorsum predominantly black ............................................................................ 8

– Hair of the thoracic dorsum yellow, often between the wing bases with many black hairs intermixed (Figs 101‒103) .......................................................................................... B. grahami ( Frison, 1933)

8. Wings pale yellow with the veins orange, the mid and hind tibiae with exoskeleton and hair bright orange (Fig. 75) (Himalaya) .......................................................................... B. genalis Friese, 1918

– Wings weakly clouded with brown with the veins brown, exoskeleton and hair of the mid and hind tibiae predominantly black (Fig. 104) (Taiwan) ........................................... B. angustus Chiu, 1948

9. Hair of the side of the thorax and scutellum predominantly black, T2‒3 with either very few or no black hairs along the midline and no transverse band of black hairs (Figs 72‒73); genitalia with the gonostylus on its outer side less than half its greatest length ( Fig. 112 ) (Sichuan, Gansu) ................ .......................................................................................................... B. validus Friese, 1905 stat. rev.

– Hair of the side of the thorax and scutellum predominantly either grey or yellow, T2‒3 usually with many black hairs along the midline and at least a narrow transverse band of black hairs either posteriorly on T2 and/or anteriorly on T3; genitalia with the gonostylus on its outer side more than half its greatest length ( Fig. 110‒111 ) (Himalaya, Hengduan) ....................................................... 10

10. 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 (Fig. 67‒69); genitalia with the gonostylus with the distal edge concave ( Fig. 111 ) (Hengduan) ..... B. nobilis Friese, 1905 s. str.

– Hair on the anterior dorsum of the thorax and of the side of the thorax and scutellum and T1 either grey-white or dull olive-yellow, T2 anterio-laterally yellow, on the scutellum in the middle the grey or yellow nearly completely divided by black (Figs 58‒60); genitalia with the gonostylus with the distal edge weakly convex ( Fig. 110 ) (Himalaya) ........................... B. sikkimi Friese, 1918 stat. rev.

Figures

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, China- Sichuan. 115. B. grahami (Frison, 1933) China-Sichuan (left penis-valve recurved hook missing). Scale bars = 1 mm.