Inventory of the Carabid Beetle Fauna of the Gaoligong Mountains, Western Yunnan Province, China: Species of the Tribe Broscini (Coleoptera: Carabidae).
Author
Kavanaugh, David H.
Department of Entomology, California Academy of Sciences, 55 Music Concourse Drive, Golden Gate Park, San Francisco, CA 94118, U. S. A.
Author
Liang, Hongbin
Key Laboratory of Zoological Systematics, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
text
Proceedings of the California Academy of Sciences
2021
2021-09-30
67
4
85
182
journal article
10.5281/zenodo.11067355
0068-547X
11067355
15.
Eobroscus bhutanensis
Morvan, 1982
Figures 5a
,
38
,
39
,
43
,
47-50
Eobroscus bhutanensis
Morvan, 1982:77
.
Holotype
, a male, deposited in
NHMB
. Type locality:
Bhutan
, near
Thimphu
.
Eobroscus uenoi
Morita, 1995:8
.
Holotype
, a male, deposited in
NSMT
. Type locality:
Vietnam
,
Lào Cai
,
Hoang Lien Son Moutains, N of Mt. Fan Si Pan,
1840 m
(synonymized by Schmidt et al. 2013:15).
Diagnosis.
Fig. 38a
. Because
E. bhutanensis
is the only species of the genus in the region, the generic diagnosis serves also to distinguish members of this species.
Habitat distribution.
Within the study area, members of this species were collected mainly under large stones at the edges small streams (
Fig. 43
), however
one specimen
was found under a stone along a roadcut though mixed broadleaf evergreen and conifer forest.
Within the Gaoligong
Shan region
, this species occurs at moderate elevations, with our records documenting its occurrence in the
2527 to 3100 m
range (
Fig. 49
).
Geographical distribution within the Gaoligong
Shan
.
Fig. 38b
.
We
examined a total of
nine specimens
(
seven males
and
two females
)
from the following localities:
Fugong County
:
Lishadi Township
(2.0 to 4.
3 km
above Shibali on Shibali Road
, 27.17262°/98.76943° to 27.17772°/98.75485°,
2700-2826 m
,
3 May 2004
,
D.H. Kavanaugh
,
H.B. Liang
&
C.E. Griswold
collectors [
one male
;
CAS
])
.
Gongshan County
:
Cikai Township
(
Danzhu
(27.63056°/98.62056°,
2600 m
,
14 April 2002
,
H.B. Liang
&
W.D. Ba
collectors [
one male
;
IOZ
]), (
Danzhu He
(13.5-13.8 airkm
SSW of Cikai
, 27.63267°/98.60861° to 27.63331°/98.60356°,
2720-2840 m
,
30 June – 5 July 2000
,
D.H. Kavanaugh
,
C.E. Griswold
,
H.B. Liang
,
D. Ubick
&
D.Z. Dong
collectors [
five males
;
CAS
,
IOZ
]), (
No.
12
Bridge Camp area
(16.3 airkm
W of Cikai
, 27.71503°/98.50244°,
2775 m
,
15-19 July 2000
,
D.H. Kavanaugh
,
C.E. Griswold
,
H.B. Liang
,
D. Ubick
&
D.Z. Dong
collectors [
one male
;
CAS
]).
Lushui County
:
Luzhang Township
(
Yaojiaping He
at
Pianma Road
, 25.97722°/98.71091°,
2527 m
,
19 May 2005
,
D.H. Kavanaugh
,
H.B. Liang
&
D.Z. Dong
collectors [
one female
;
IOZ
]).
FIGURE
38.
Eobroscus bhutanensis
Morvan.
a. Habitus (CASENT1019340; Lishadi Township, Fugong County, Yunnan, China), dorsal aspect, scale line = 1.0 mm; b. Map showing locality records (blue circles) for this species in the Gaoligong Shan region, scale line = 100 km.
FIGURE
39. Male genitalia,
Eobroscus bhutanensis
Morvan
(CASENT1001452; Danzhu He drainage, Gongshan County, Yunnan, China). a. Right paramere, lateral aspect; b. Left paramere, lateral aspect; c. Median lobe, left lateral aspect; d. median lobe, ventral aspect; scale line = 1.0 mm.
Members of this species were collected only in the northern two-thirds of the study area, in Core Areas 2, 3 and 5 (
Fig. 48
), and only on the eastern side of the mountain range. However, the relatively broad geographical range of this species overall (see below) suggests that it probably occurs in the other cores areas as well but has not yet been recorded from them.
Overall geographical distribution.
Fig. 47
. This species has been recorded from
Bhutan
,
China
(
Gansu, Shaanxi, Sichuan, Xizang
(
Tibet
),
Yunnan
),
India
(
Arunachal Pradesh
),
Myanmar
,
Nepal
, and northern
Vietnam
. Its occurrence in the study area is near the midpoint of both its known east/west and north/south geographical ranges
.
Geographical relationships with other
Eobroscus
species.
Representatives of neither of the other
Eobroscus
species
have been recorded from within the study area or from any other area where
E. bhutanensis
has been found with one exception. A single specimen of
E. lutshniki
(in
IOZ
) that we examined is labeled [in Chinese characters] as from Lazikou,
Gansu Province
,
China
, an area about
2500 km
SW of the nearest verified localities for that species. A specimen of
E. bhutanensi
s (also in
IOZ
) bears the same locality label. It is most likely that the specimen of
E. lutshniki
was mislabeled; but if not, then this would represent the only known instance of sympatry of species in the genus.
Within the study area,
E. bhutanensis
has been found in the same area and habitat as two other broscine species,
Broscosoma danzhuense
and
B. ribbei
(
Fig. 50
).
FIGURE
40. Photographs of habitats for broscine species in the Gaoligong Shan region. a. SW slope of Kawakarpu Shan on slope NE of Chukuai Lake, 3950 m, 27.982°/098.480°, Bingzhongluo Township, Gongshan County, Yunnan (habitat for
Brosocodera chukuai
sp. nov.
); b. Second cirque S of Shibali Yakou at border post “31”, 3710 m, 27.203°/098.693°, Lumadeng Township, Fugong County, Yunnan (habitat for
Brosocodera chukuai
sp. nov.
,
Broscosoma furvum
sp. nov.
, and
Broscosoma viridicollare
sp. nov.
). Photos by David H. Kavanaugh.
FIGURE
41. Photographs of habitats for broscine species in the Gaoligong Shan region. a. 1.3 km E of Lao Shibali, South Fork of Yamu He, 2250 m, 27.082°/98.787°, Lumadeng Township, Fugong County, Yunnan (habitat for
Brosocodera gaoligongensis
sp. nov.
; b. Danzhu He drainage, 2700 m, 27.631°/98.621°, Gongshan County, Yunnan (habitat for
Broscodera gaoligongensis
sp. nov.
and
Broscosoma ribbei
Putzeys
). Photos by David H. Kavanaugh.
FIGURE
42. Photographs of habitats for
Broscosoma
species
in the Gaoligong Shan region. a. Dulong/Gongshan Yakou area, 3300-3680m, 27.697º/098.454º, Gongshan County, Yunnan (habitat for
Broscosoma bicoloratum
sp. nov.
and
B. gongshanense
sp. nov.
); b. Southeastern slope of Heipu Yakou, 3365m, 27.770º/098.447º, Cikai Township, Gongshan County, Yunnan (habitat for
Broscosoma bicoloratum
sp.
nov.
). Photos by David H. Kavanaugh.
FIGURE
43. Photographs of habitat for broscine species in the Gaoligong Shan region; a. Danzhu He drainage, 2840 m, 27.633°/98.604°, Cikai Township, Gongshan County, Yunnan (habitat for
Broscosoma danzhuense
sp. nov.
and
Eobroscus bhtanensis
Morvan
). Photo by David H. Kavanaugh.
FIGURE
44. Photographs of habitats for
Broscosoma
species
in the Gaoligong Shan region. a. 0.5 km E of Fengxue Yakou, 3150 m, 25.972º/098.683 º, Luzhang Township, Lushui County, Yunnan (habitat for
Broscosoma gaoligongense
sp. nov.
); b. Xiao Jiang at Gangfang Sancha Lukou, 1500 m, 26.122º/98.573º, Lushui County, Yunnan (habitat for
Broscosoma holomarginatum
sp. nov.
). Photos by David H. Kavanaugh.
FIGURE
45. Photographs of habitats for
Broscosoma
species
in the Gaoligong Shan region. a. Snowmelt stream on north-facing slope above North Fork of Yamu He, 8.5 km W of Shibali, 3100-3200 m, 27.18315º/098.71921º, Lumadeng Township, Fugong County, Yunnan (habitat for
Broscosoma parvum
sp. nov.
); b. 0.6 km N of Dizhengdang village on Dulongjiang, 1880 m, 28.084º/098.327º, Dulongjiang Township, Gongshan County, Yunnan (habitat for
Broscosoma purpureum
sp. nov.
). Photos by David H. Kavanaugh
FIGURE
46. Photographs of habitats for broscine species in the Gaoligong Shan region. a. Siran Wang, 0.2 km above confluence with Dulong Jiang, 1720 m, 28.013°/ E098.321º, Dulongjiang Township, Gongshan County, Yunnan (habitat for
Broscosoma resbecqi
sp. nov.
); b. Nankang Yakou, 2130 m, 24.828°/98.767°, Longyang County, Yunnan (habitat for
Broscosoma ribbei
Putzeys
and
Broscus punctatus
(Dejean)
. Photos by David H. Kavanaugh.
FIGURE
47. Map showing approximate known overall geographical distributions of
broscine
species occurring in the Gaoligong Shan region as well as outside the study area. a.
Broscus punctatus
(Dejean)
; b.
Eobroscus bhutanensis
Morvan
; c.
Broscosoma ribbei
Putzeys
; d.
Broscosoma holomarginatum
sp. nov.
Modified from Wikimedia Commons, World Atlas of the World, at URL: http://upload.wikimedia.org/wikipedia/commons/8/8f/Whole_world_-_land_and_oceans_12000.jpg. Scale line = 500 k
FIGURE
48. Chart showing the representation of broscine species in project-designated Core Areas (see Fig. 3) in the
Gaoligong Shan region.
FIGURE
49. Chart illustrating the altitudinal ranges of broscine species represented in the Gaoligong Shan region.
Green bars mark the elevational range recorded for each species.
FIGURE
50. Chart illustrating the co-occurence (syntopy) of broscine species in samples from the same habitats and at the same sites in the Gaoligong Shan region. Incidents of syntopy marked in black represent confirmed co-occurrence, those marked in grey not confirmed by records but likely.
Discussion
The Gaoligong
Shan region
is a key component of one of the world’s biodiversity hotspots (
Myers et al. 2000
), where faunal elements from the Palearctic and
Oriental
Regions
meet. These elements augment a distinct regional, largely precinctive element, probably of mixed Palearctic/
Oriental
origin (
Deuve 2013
), which either became isolated and evolved independently within the region or has been replaced elsewhere by present-day Palearctic and/or
Oriental
elements. Among the four groups studied in detail to date, the trechines and broscines are the most diverse precinctive elements in the fauna, with 25 of 29 trechine species (86%) and 11 of 15 broscine species (73%) known from nowhere else. We have found no precinctive species among either the omophronines (three species) or the zabrines (13 species).
Relative to the diversity of faunas in other areas of comparable size, the broscine fauna of the Gaoligong
Shan region
is exceptionally diverse and previously poorly known. Of the 15 species from the area recorded here, 11 are described as new and one additional species,
Broscosoma gaoligongense
,
which we also had represented in our samples as new, was only recently described by
Deuve and Wrase (2015)
. This diversity includes not only taxonomic diversity, but also exceptional diversity in morphological features, particularly within the genus
Broscosoma
, but also in
Broscodera
to a lesser degree.
No other comparable region is known to harbor two species of
Broscodera
. Their geographical ranges overlap in part but they appear to occupy different elevational ranges and are also non-overlapping in their respective body size ranges. Members of
Broscodera chukuai
are the smallest members of the genus known to date, with their size range outside the ranges of any of the other congeneric species and subspecies. Whether the differences in body size and elevational range between
B. chukuai
and
B. gaoligongensis
represent character displacement in these morphological and ecological features or have instead resulted from some other historical cause or causes will remain unclear until phylogenetic relationships among
Broscodera
species
are better understood.
There appears to us to be at least as much morphological diversity within the
Broscosoma
fauna of the Gaoligong
Shan region
as is found within the genus throughout the remainder of its entire range. All species with members having lateral margination of the pronotum present, whether distinct on at least part of the pronotal margin, as in
B. resbecqi
and
B. ribbei
, or complete, as in
B. holomarginatum
, are found in this region.
Broscosoma rebecqi
is known only from this region,
B. holomarginatum
also occurs in the adjacent southeastern part of Xizhang (
Tibet
), and only
B. ribbei
is more widely distributed. No other area has as many species with the elytra humeri more or less distinct. In fact, the number of species with distinct humeri in the Gaoligong
Shan region
(six) is double the number (three) within the remainder of the genus. Diversity in the presence and distribution of metallic reflection on the dorsum of the body is also exceptional. For example, no described species from any another area has members which have the pronotum without metallic reflection except for the area anterior to the anterior transverse impression, where it is distinctly present in
B. viridicollare
members and faintly present in some members of
B. bicoloratum
as well. Finally, there is exceptional diversity in the genitalic structures of males in the region, particularly in the shape of the median lobe and the sclerites of its internal sac and in the shape of the left paramere. Clearly, the Gaoligong
Shan region
is and has been a very important area in the evolutionary history of this genus. Better understanding of that history will require phylogenetic analyses of both morphological and DNA data for the genus as a whole.