Widespread polytypic species or complexes of local species? Revising bumblebees of the subgenus Melanobombus world-wide (Hymenoptera, Apidae, Bombus)
Author
Williams, Paul H.
Natural History Museum, Cromwell Road, London SW 7 5 BD, UK. Institute of General and Experimental Biology, Peace Avenue 54 b, Ulaanbaatar 13330, Mongolia. Novosibirsk State University, ul. Pirogova 2, Novosibirsk, 630090 Russia. Langstraat 105, B- 2260 Westerlo, Belgium. South China Agricultural University, Guangzhou 510642, China. Agricultural University of Georgia, 240 Agmashenebli Alley, Tbilisi, Georgia. Indonesian Institute of Sciences (LIPI), Jakarta, Indonesia. Kunming Institute of Botany (Chinese Academy of Sciences), 132 Lanhei Road, Kunming, Yunnan 650201, China. Università di Roma ‘ Sapienza’, Piazzale Valerio Massimo 6, Roma 00162, Italy. Yasouj University, Zirtol, Yasouj, Iran. Sherubtse College, Royal University of Bhutan, Trashigang, Bhutan. Zoological Survey of India, Pali Road, Jodhpur 342005, Rajasthan, India. Institute of Zoology (Chinese Academy of Sciences), 1 Beichen West Road, Chaoyang, Beijing 100101, China.
paw@nhm.ac.uk
Author
Altanchimeg, Dorjsuren
altanchimegd@mas.ac.mn
Author
Byvaltsev, Alexandr
byvam@yandex.ru
Author
Jonghe, Roland De
roland.de.jonghe@telenet.be
Author
Jaffar, Saleem
saleemjaffar@stu.scau.edu.cn
Author
Japoshvili, George
g.japoshvili@agruni.edu.ge
Author
Kahono, Sih
sihkahono@gmail.com
Author
Liang, Huan
lianghuan@mail.kib.ac.cn
Author
Mei, Maurizio
Author
Monfared, Alireza
Author
Nidup, Tshering
Author
Raina, Rifat
Author
Ren, Zongxin
Author
Thanoosing, Chawatat
Author
Zhao, Yanhui
Author
Orr, Michael C.
text
European Journal of Taxonomy
2020
2020-10-02
719
1
120
journal article
9775
10.5852/ejt.2020.719.1107
7ca72f76-4fae-4305-8601-4662f4cd2b96
4064324
A4500016-C219-4353-B81C-5E0BB520547F
Bombus separandus
Vogt, 1909
stat. rev.
Figs 16
,
173–180
,
204
,
210
,
212
Bombus lapidarius
Form [subsp.]
separandus
Vogt, 1909: 61
.
Bombus lapidarius
Form [subsp.]
kohli
Vogt, 1909: 61
(non
Cockerell, 1906: 75
=
B. morio
(Swederus))
.
syn. nov.
Bombus kozlovi
Skorikov, 1910a: 413
, replacement name for
kohli
Vogt, 1909: 61
.
syn. nov
.
Bombus lapidarius
var. [subsp.]
tenellus
Friese, 1913: 86
.
syn. nov
.
Bombus tenellus
var. [not subsp.]
alpivagus
Richards, 1930: 639
, but not infrasubspecific after
Reinig 1935: 333
(
ICZN 1999
: Art. 45.6.4.1).
syn. nov.
Lapidariobombus alagesianus
subsp.
pamirus
Skorikov, 1931: 226
(non
Skorikov, 1931: 232
=
B. oberti
Morawitz
, not
B. difficillimus
Skorikov
as given by Skorikov).
syn. nov.
Lapidariobombus alagesianus
subsp.
mongolicus
Skorikov, 1931: 226
(non
Friese, 1916: 110
?=
B. diversus
Smith
).
syn. nov.
Bombus keriensis
f.g. [subsp.]
bucharicus
Reinig, 1935: 340
.
syn. nov.
Bombus keriensis
f.g. [subsp.]
richardsi
Reinig, 1935: 341
(non
Frison, 1930: 6
=
B. rufipes
Lepeletier
).
Bombus tenellus
subsp.
tibetensis
S.-F.
Wang, 1982: 439
, replacement name for
richardsi
Reinig, 1935: 341
.
syn. nov.
Bombus kozlowi
–
Bischoff, 1936: 9
, unjustified emendation.
Bombus keriensis
(part) –
Reinig 1935: 341
. —
Williams 1998: 134
(non
Morawitz, 1887: 199
).
Vogt (1909: 46)
stated that his “Formen” are subpopulations, which can be considered equivalent to subspecies.
Reinig (1935: 333)
stated explicitly that his “f.g.” (
forma geographica
) are equivalent to subspecies.
Vogt (1909: 61)
described his taxon
separandus
as having the hair of the face and top of the head (“Gesicht und Stirn”) black and the underside of the thorax dark haired. He described his taxon
kohli
(later renamed
kozlovi
) as having the face with a few yellow hairs. However,
Vogt (1911: 58)
then characterised the taxon
separandus
as differing from the taxon
keriensis
only in having an absence of pale hairs on the face (he did not include the taxon
kohli
/
kozlovi
as part of the taxon
separandus
but did include the taxon
incertoides
as part of
separandus
). The taxon
separandus
was treated as a part of the species
B. keriensis
s. lat.
by
Reinig (1935)
and by
Williams (1998)
.
Our PTP analysis (
Fig. 10
) of coalescents in the COI gene within the
keriensis
-complex supports six species including
B. separandus
, corroborated by differences in morphology. These species are also supported by the absence of a positive divergence-with-distance relationship among them (
Fig. 20
) (see Divergence and geographical distance, page 12).
From morphology, after examining>1000 specimens of the
keriensis
-group from across Asia and after comparing the distribution of states of several characters as part of this study (PW), Vogt’s character state of exclusively black hair on the face does appear to remain one of the most consistently diagnostic characters (in comparison with COI sequences) for
B. separandus
in the QTP and Central Asia, at least for queens (but see the comments on
B. keriensis
). Nonetheless, there are some individuals of the yellow-banded taxon
kozlovi
from
Mongolia
(part of
B. separandus
s. lat.
according our COI-coalescent results,
Fig. 10
) that do have a few yellow hairs on the face, so that exclusively black hair on the face is not diagnostic in all parts of the range. Several aspects of the colour pattern vary strongly within the species: (1)
B. separandus
includes both yellow-banded and white-banded colour patterns; (2) the extent of the black hair between the wing bases varies; (3) the extent of the pale hair on the side and ventral area (leg bases) of the thorax varies; (4) the extent of the pale hair posteriorly on T3 varies (the ‘ciliation’ of authors); (5) the contrast of the pale posterior fringes on T4–5 varies. Many of these characters might appear to show a continuum of variation that is also continuous with the variation within
B. keriensis
s. str.
(
Williams 1991
), which might then appear consistent with the two taxa being parts of the same species (
Reinig 1935
). However, as noted above, evidence from COI barcodes shows that the two genecoalescent groups differ most consistently in the absence of pale hairs on the face for
B. separandus
, supporting Vogt’s characterisation of the species, providing integrated morphological support for its status as a separate species. The overlapping colour variation of
B. separandus
but only in
Mongolia
(where
B. keriensis
s. str.
does not occur) does not negate the fact that
B. separandus
is recognisable by morphological characters throughout its geographical range.
Figs 209–210.
Images of queens of two cryptic species from around the western Qinghai-Tibetan plateau.
209
.
Bombus keriensis
Morawitz, 1887
from Mt Apharwat (4000 m a.s.l.) in the Pir Panjal mountains (ML405).
210
.
B. separandus
Vogt, 1909
stat. rev.
from Nimaling plain (4800 m a.s.l.) in the Zanskar mountains (ML311). Viewed from the left lateral aspect.
There are some queens of the yellow-banded taxon
richardsi
(later renamed
tibetensis
) from the northwestern QTP that have no pale hairs on the face, very few or no yellow hairs on the leg bases, and very few black hairs within the yellow bands of the thoracic dorsum. Many of the available specimens have failed to sequence, so the species’ diagnosis remains tentative. Particularly influential in the interpretation of these individuals is one yellow-banded queen with a reduced extent of pale hair on the side of the thorax from the Zanskar range (PW: ML311,
Figs 177
,
210
), which has produced a short sequence (382 bp) that nonetheless shows bases diagnostic for
B. separandus
compared to
B. keriensis
(base positions 267A, 286C, 301C, 306T, 339T, 363C, 423T, 498C, 529G, 540T, 541C, 556C). This is one of the specimens that most closely resemble some yellow-banded individuals of the candidate species
keriensis
s. str.
also from Kashmir (
Figs 170
,
209
) (the difference in the breadth of the black band between the wings is not diagnostic for these species).
Bombus separandus
co-occurs locally with the similar
B. incertoides
in the Altai and Khangai mountains of
Mongolia
.
Bombus separandus
also co-occurs locally with the similar
B. keriensis
s. str.
in the Zanskar mountains of Kashmir. Examination of specimens in the IOZ collection labelled
B. incertus
(S.-F.
Wang 1985
; S.-F.
Wang & Yao 1996
;
Niu
et al.
2018
) shows that these are mostly misidentified
B. separandus
(with a few
B. keriensis
) from Xinjiang.
Diagnosis
Females
Queens medium-sized body length
17–20 mm
, workers
9–14 mm
. Can be distinguished in Central Asia and
Mongolia
by the combination of hair of the face usually without pale hairs (except in
Mongolia
where
B. keriensis
does not occur), the leg bases usually without pale hairs, T2 posteriorly entirely pale without black hairs, and T3 laterally usually without pale hairs (cf.
B. sichelii
,
B. keriensis
).
Males
Body length
10–15 mm
. Can be distinguished reliably at present only by their COI sequence, although in the western Himalaya they may be distinguished by entirely black hair between the wing bases and hair of T3 entirely black. Genitalia (
Fig. 204
) with the gonostylus shorter than broad, its inner basal projection reduced to a short stub (cf.
rufipes-
group,
festivus-
group,
rufofasciatus
-group); volsella with the inner distal corner broadly produced but without a narrow hook (cf.
rufipes-
group,
festivus-
group,
rufofasciatus
-group); eye unenlarged relative to female eye.
Material examined
Lectotype
CHINA
•
♀
(queen),
lectotype
of
Bombus lapidarius
Form
separandus
Vogt, 1909
by designation of
Williams (1991: 97)
;
Xinjiang
, Borohoro Shan, Tisilikau;
RMNH
(examined
PW
).
Material sequenced
(
25 specimens
)
MONGOLIA
•
1 ♀
(queen);
Bulgan
;
47.4257° N
,
103.6940° E
;
22 Jun. 2013
;
NHMUK
seq: NHMSR1;
PW
:
ML147
•
1 ♀
(worker);
Bayanolgiy
,
Bulgan
;
46.9333° N
,
91.1667° E
;
26 Jul. 1992
;
Culverwell
leg.; BOLD seq: 6877B11;
PW
:
ML151
•
1 ♀
(queen);
Khenteyn Nuruu
,
Terelj
;
47.9905° N
,
107.3719° E
;
16 Jun. 2015
;
R. DeJonghe
leg.; BOLD seq: 6877A08; RJ: ML333
•
1 ♀
(queen);
Khenteyn Nuruu
,
Terelj
;
47.9956° N
,
107.3303° E
;
17 Jun. 2015
;
R. DeJonghe
leg.; BOLD seq: 6880B05;
RDJ
:
ML489
•
1 ♀
(worker);
Arkhangai
,
Chuluut Khujirt Mts
;
47.5750° N
,
101.1092° E
;
11 Aug. 2018
;
R. DeJonghe
leg.; BOLD seq: 6880B12;
RDJ
:
ML497
.
RUSSIA
•
1 ♀
(worker);
Altai
,
Ulagansky
,
6 km
NE of Aktash
;
50.3158° N
,
87.7036° E
;
6–7 Jul. 2017
;
S. Knyazev
leg.; BOLD seq: 1555F07;
PW
:
ML264
•
1 ♀
(worker);
Altai
,
Ulagansky
,
8 km
NE of Aktash
;
50.3160° N
,
87.7253° E
;
5–6 Jul. 2017
;
S. Knyazev
leg.; BOLD seq: 1555F08;
PW
:
ML265
•
1 ♀
(worker);
Tuva
,
27 km
S of Erzin
;
50.0049° N
,
95.1719° E
;
11–12 Jul. 2014
;
A. Lelej
leg.; BOLD seq: 1555F09;
PW
:
ML266
•
1 ♀
(worker);
Tuva
,
25 km
of
Erzin
;
50.1611° N
,
95.4778° E
;
14–15 Jul. 2014
;
A. Lelej
leg.; BOLD seq: 1555F10;
PW
:
ML267
•
1 ♀
(worker);
Tuva
,
31 km
of
Erzin
;
50.0366° N
,
95.4348° E
;
18 Jul. 2014
;
A. Lelej
leg.; BOLD seq: 1555F12;
PW
:
ML269
•
1 ♀
(worker); same collection data as for preceding;
16 Jul. 2014
;
A. Lelej
leg.; BOLD seq: 1555G01;
PW
:
ML270
.
KYRGYZSTAN
•
1 ♀
(queen);
Jalalabad
,
Jylamysh
;
42.6522° N
,
74.4812° E
;
27 May 2009
;
L. Best
leg.; BOLD seq: 1552H03;
PW
:
ML156
•
1 ♀
(queen);
Oshakaya
,
Kyzyl-Suu
;
39.4761° N
,
71.8933° E
;
18 Jul. 1998
;
H. Rausch
leg.; BOLD seq: 1552A08;
OLML
:
ML191
•
1 ♀
(worker);
Chong Aksuu Valley
nr
Karakol lake
;
42.8386° N
,
77.3889° E
;
26 Jun. 2016
;
R. DeJonghe
leg.; BOLD seq: 1555F04; RJ: ML261
•
1 ♀
(worker); same collection data as for preceding; BOLD seq: 1555F05; RJ: ML262
•
1 ♀
(worker); same collection data as for preceding; BOLD seq: 1555F06; RJ: ML263
•
1 ♀
(queen);
Kungey Ala-Too
,
Chong Aksuu
nr
Karakol lake
;
42.8397° N
,
77.37° E
;
25 Jun. 2016
;
R. DeJonghe
leg.; BOLD seq: 6877A09; RJ: ML336
•
1 ♀
(queen);
Terskey Ala-Too
,
Turgon-Aksuu river
;
42.4183° N
,
78.9467° E
;
2 Jul. 2016
;
R. DeJonghe
leg.; BOLD seq: 6877A11; RJ: ML341
•
1 ♀
(queen); same collection data as for preceding; BOLD seq: 6877A10; RJ: ML342
•
1 ♀
(queen);
Terskey Ala-Too
,
Turgon-Aksuu river
;
42.4019° N
,
79.0486° E
;
3 Jul. 2016
;
R. DeJonghe
leg.; BOLD seq: 6877A12; RJ: ML343
•
1 ♀
(queen);
Terskey Ala-Too
,
Saruu
,
Juktuu river
;
42.0947° N
,
77.9617° E
;
6 Jul. 2016
;
R. DeJonghe
leg.; BOLD seq: 6877B01; RJ: ML348
•
1 ♀
(queen);
Santash
;
42.7389° N
,
79° E
;
29 Jun. 2016
;
R. DeJonghe
leg.; BOLD seq: 6877B02; RJ: ML356
•
1 ♀
(queen); same collection data as for preceding; BOLD seq: 6877B03; RJ: ML357
.
PAKISTAN
•
1 ♀
(worker);
Chitral
,
Khyber-Pakhtunkhwa
,
Tirich Valley
;
36.3150° N
,
71.9824° E
;
8 Aug. 1984
;
W. Budenburg
leg.; BOLD seq: 6877C02;
PW
:
ML383
.
INDIA
•
1 ♀
(queen);
Kashmir
,
Zanskar
,
Nimaling Plain
;
33.7927° N
,
77.5881° E
;
15 Jul. 1980
;
P. Williams
leg.; BOLD seq: 1555H10;
PW
:
ML311
.
Global distribution
(Central Asian and Mongolian mountain species extending into the northwestern corner of the QTP)
North Asia
:
MONGOLIA
,
RUSSIA
:
Tuva
,
Altai
Mountains. –
Central Asia
:
KAZAKHSTAN
,
KYRGYZSTAN
,
TAJIKISTAN
. –
East Asia
:
CHINA
:
Xinjiang
. –
Himalaya
:
PAKISTAN
,
INDIA
: Kashmir. (IAR, IOZ, NHMUK, OLML, PW, RDJ, RMNH, ZIN, ZMHB.). This species is widespread and can be common (
Fig. 212
).
Behaviour
Very few food-plant records but expected to be generalists (
Caragana versicolor
in
Williams 1991
). The male mate-searching behaviour is expected to resemble the patrolling of
B. keriensis
s. str.