Inventory of the carabid beetle fauna of the Gaoligong Mountains, western Yunnan Province, China: species of the tribe Zabrini (Coleoptera, Carabidae)

Abstract A ten-year multidisciplinary, multi-national and multi-institutional biodiversity inventory project in the Gaoligong Shan region of western Yunnan Province, China generated more than 35,000 specimens of the beetle (Coleoptera) family Carabidae. In this report, first of a planned series, we focus on diversity in tribe Zabrini. Our study of just over 1300 specimens of zabrine carabids from the project, all in genus Amara Bonelli, found a total of 13 species, all previously described, to occur in the study area, with none of them strictly endemic. We present a key for identification of adults of these species, as well as nomenclatural data, diagnoses, illustrations of dorsal habitus and male genitalia, and information about geographical, altitudinal and habitat distributions within the study area and overall geographical distribution for each species. Distributions of the species within the study area are compared, and broader geographical range patterns are characterized. We also discuss a possible role of the Gaoligong Shan region as one source area for the present-day fauna of the Himalaya and southern edge of the Qinghai-Xizang (Tibetan) Plateau.


Introduction
The Gaoligong Shan (Gaoligong Mountains) of extreme western Yunnan province, China, form the westernmost range of the Hengduan Mountains system of southeastern Xizang Autonomous Region (Tibet), northern and western Yunnan, and western Sichuan (Fig. 1). They extend north to south for more than 600 km, and, in the central part of the range, their crest forms the border between China and Myanmar. They also separate and form parts of the watersheds of two of Southeast Asia's major rivers, the Irrawaddy and the Salween (known in China as the Nujiang). Elevations within the region range from a low of about 650 m in the south to more than 5000 m in the north. Chaplin (2006) reviewed the physical geography of the region. Because of its geographic isolation and rugged topography, much of this area has remained less disturbed than most other parts of China; and previous biological exploration of the area over the past 150 years has revealed exceptionally high species richness, based almost exclusively on records for vertebrates (e.g., Stattersfield et al. 1998) and vascular plants (Li et al 2000). Because of these traits, two large nature reserves have been established in the area, and the region has been included in the Three Parallel Rivers of Yunnan World Heritage Site (UNESCO 2003).
In late 1997, the California Academy of Sciences was invited to participate in a joint project with the Kunming Institutes of Botany and Zoology of the Chinese Academy of Sciences to conduct a biodiversity inventory of the Gaoligong Mountains. Scientists from several additional institutions, including the Institute of Zoology, Beijing, and Royal Botanical Garden (Edinburgh) joined in the collaboration. Principal target groups for the inventory included bryophytes and vascular plants, all vertebrate groups, and arachnids, myriapods, and insects, especially the Neuropteroidea, Mecoptera, and Coleoptera (the Carabidae in particular). Multidisciplinary and multi-institutional teams carried out biotic sampling through more than 25 separate expeditions during the period 1998 to 2007. More than 100 reports on the project have been published to date, including partial results for bryophytes (e.g., Long 2006, Shevock 2005, plants (e.g., Fritsch et al. 2008, Zhou et al. 2006, birds (Dumbacher et al. 2011), amphibians (e.g., Liu et al. 2000), fishes (e.g., Chen et al. 2005), spiders (e.g., Miller et al. 2009, Wang et al. 2010, and carabid beetles (Kavanaugh andLiang 2004 andKavanaugh and Long 1999;Liang and Imura 2003;2007;andLiu et al. 2010 and. Prior to the start of the project the carabid beetle fauna of the region was very poorly known. The faunal for the entire Hengduan region included only about 50 species (Yu 1992), and most of these were widespread species from low elevation areas. The region in general and the higher elevations in particular were virtually unexplored with respect to the carabid fauna. As a result of our work on this project to date, we now recognize more than 525 species occurring in the Gaoligong Shan, with many additional species undoubtedly represented among materials for groups not yet fully studied. For several of the groups currently under study, (e.g., Leistus (Nebriini), Broscosoma (Broscini), Amerizus (Tiruka) (Bembidiini) and Aristochroa (Pterostichini), species diversity is much higher in this area than is known anywhere else that these taxa occur.
This report, on the tribe Zabrini, represents the first of an intended series of treatments on the carabid beetle fauna of the Gaoligong Shan region, each dealing with one or more tribes or hyper-diverse genera represented in the fauna. These will appear as taxonomic work on each group is completed and not in any particular taxonomic or phylogenetic order.
Zabrini is a moderately diverse taxon, including nearly 700 described species (Lorenz 2005). It is principally Holarctic in distribution, with relatively few species occurring south of that region in the Neotropical (as far south as Costa Rica), Afrotropical (nine species in Ethiopia, Kenya, Somalia and Tansania) and Oriental (three or four species in northern parts only) Regions. The only zabrine genus represented in the study area is Amara Bonelli (1810), which is also the largest genus in the tribe, with just over 570 described species and a cumulative geographical range which actually defines that of the tribe. The ranges of the other zabrine genus, Zabrus Clairville (1806), and of Pseudamara Lindroth (1968), which has been transferred from the Zabrini to the Sphodrini recently by Hieke (2010Hieke ( , 2013, are fully within the range of Amara. Amara is most diverse in temperate parts of the Holarctic Region. Along with members of the tribe Harpalini, zabrines are unusual among Carabidae in feeding mainly on seeds (Johnson and Cameron 1969), particularly those of the grass (Graminaceae) and mustard (Cruciferae) families, but also on fruits, flowers and other plant parts. Apparently, both adults and larvae use seeds as a main food source. Probably because of their feeding preferences, Amara species occur mainly in open areas, such as grasslands, meadows, forest edges, and disturbed habitats of all types, including both those associated with natural environmental processes (e.g., landslides, eroded or scoured stream banks, floodplains and areas burned by lightning strikes) and those created by humans (e.g., forest clearings, roadcuts and ruderal (waste) sites around human settlements or other constructs and agricultural sites).
As is the case with most other terrestrial anthropod groups, the Amara fauna of the study area has not been well documented previously. Most of our current knowledge of the Southeast Asian regional fauna is from the works of Baliani ( , 1934aBaliani ( , 1934bBaliani ( , 1937Baliani ( , 1943, Hieke (see References section) and Jedlička (1934aJedlička ( , 1934bJedlička ( , 1956Jedlička ( , 1957, with significant additional contributions from Andrewes (1930), Bates (1876Bates ( , 1883Bates ( , 1891, Morawitz (1863aMorawitz ( , 1863b, Motschulsky (1844), Putzeys (1875) and Tschitschérine (1894Tschitschérine ( , 1897Tschitschérine ( , 1899. Based on our study of the material collected for the project and additional specimens from the region housed in other collections, we recognize a total of 13 Amara species found to occur in the study area, all of which have been described previously. We present here a key for identification of adults of these species, as well as nomenclatural data, diagnoses, illustrations of dorsal habitus and male genitalia, and information about geographical and habitat distributions within the study area and overall geographical distribution for each species. We also discuss geographical distributions of the species with respect to seven core areas and to each other, as well as broader geographical range patterns and the altitudinal ranges of the species.

Materials and methods
The natural physiographic limits of the study area for the project are as shown in Fig. 2 and include areas in eastern Myanmar and southern Xizhang (Tibet); but we had permission to survey only those parts in Yunnan Province. Specialists for all taxonomic groups concentrated their efforts on seven core areas within the project region (Fig. 3), selected to facilitate comparisons of possible north to south and east to west spatial differences within the regional biota, as well as recognition of areas of local endemism. Other areas were sampled as time and opportunity permitted. The entomological team made a total of 13 expeditions to the Gaoligong region. Our sampling sites within the region are shown in Fig. 4. Habitats included in the study area range from subtropical lowland rainforest to the margin of glaciers and snowfields. In all, more than 35,000 carabid specimens were collected during the project by using a variety of collecting methods, including hand collecting both day and night, beating vegetation, sifting litter with subsequent extraction by hand or by mini-Winkler units, and Malaise flight traps and pitfall traps. All specimens were sorted to morphospecies (i.e., presumptive species units based on features of external structure and male and female genitalic traits) and detailed systematic studies of taxonomic groups are ongoing.
A total of 1,327 specimens representing zabrine species were collected during the project. All of these specimens have been divided among and are deposited in collections of our home institutions. Codens used throughout this report for collections in which specimens, including primary types, are deposited are as follows: 1 Medial protibial spurs trifid (Fig. 5a); dorsal surface dark metallic green, nonmetallic black in a very few specimens; body length 7.0-8.5 mm; elytron with parascutellar pore-puncture present ... A. (Zezea) davidi Tschitschérine, 1897 -Medial protibial spurs simple (Fig. 5b)  Base of pronotum coarsely punctate; outer basal impressions shallow and obliquely linear (Fig. 11a); male aedeagus with median lobe distinctly broader in apical one-third than more basally, apical lamella shorter, broadly rounded apically and with sides only slightly convergent subapically (Fig. 11c); sclerites of internal sac of median lobe of male aedeagus as in Fig. 7a Dorsal surface light-brown to brownish black, without metallic reflection, entire legs and antennae pale; body length 6.5-8.0 mm; male aedeagus with apical third of median lobe broader than middle third (Fig. 21c), apical hook of right paramere large and slightly subapical (Fig. 8a)  Elytral microscuplture comprised of distinctly isodiametric meshes in both males and females (more deeply impressed in females than in males); pronotum (Figs13a, 15a, 17a) more distinctly narrowed anteriorly than basally, anterior margin clearly narrower than posterior margin, pronotal base moderately coarsely punctate, outer basal impressions either not sharply delimited laterally by raised areas or, if so, then the raised area broader .................... 11 11 Pronotum (Fig. 15a) with posterior angles distinctly rounded (narrowly so in some individuals), slightly to moderately obtuse; elytra with slight sub-basal depressions centered on striae 6 (visible on right elytron in Fig. 15a), also on striae 4 and/or 5 in some individuals; dorsal surface black, with very faint metallic blue or green metallic reflection in most individuals, more vivid (as in Fig. 15a) in or lacking from a few specimens; body length 8. Diagnosis. Adults of this species (Fig. 9) can be distinguished from those of all other species in the region by their trifid medial protibial spurs (Fig. 5a). Amara davidi is the only member of subgenus Zezea, members of which share this feature, known from the region. Habitat distribution. Specimens of this species were collected from under stones in open roadside and waste areas ( Fig. 22a) with scattered grasses and shrubs at elevations ranging from 2020 to 2440 m, syntopic (together in the same habitat) with adults of A. birmana, A. shaanxiensis, A. sikkimensis and A. silvestrii at one or more sites.
Geographical distribution within the Gaoligong Shan. Fig. 9d. We examined a total of 3 specimens (all females) from the following localities: Gongshan County: Heiwadi (16.8  Members of this species were collected in both the northern and southern parts of the study area (Core Areas 2, 6 and 7) but not in the central part. This gap in distribution is most likely an artifact of inadequate sampling and not a real disjunction.

Amara
Diagnosis. Adults of this species (Fig. 10) can be distinguished from those of all other species in the region by the following combination of character states: body length 9-10 mm; base of the pronotum evenly convex from one side to the other, outer basal impressions absent or only very faintly suggested; elytra with parascutellar pore puncture present; medial protibial spurs simple; tarsomere 5 of hind tarsi with two or (in a few specimens) three pairs of setae ventrally (Fig. 6b); last abdominal sternite of male with one pair (Fig.5e) and female with two pairs (Fig.5c) of setiferous punctures near hind margin; sclerites of internal sac of median lobe of male aedeagus with form as in Fig. 7e-f. Habitat distribution. Specimens of this species were collected in daytime from under stones and other cover in open roadside areas with scattered grasses and shrubs (Fig. 22b), at the edges of agricultural fields, including wet and dry rice paddies, and on open banks of streams, and in these same habitats at night, when beetles were found active on bare substrate. Specimens were found at elevations ranging from 892 to 2000 m. The only other Amara species members of which were found syntopic with those of A. congrua was A. latithorax, with adults of both species found together at only one site at an elevation of 1223 m.
Geographical distribution within the Gaoligong Shan. Fig. 10d. We examined a total of 33 specimens (17 males and 16 females) from the following localities: Members of this species were collected from the northern to the southern parts of the study area (Core Areas 2, 3, 5 and 6), but they were found only on the eastern side of the mountain range in northern and central areas (Core Areas 2,3 and 5) and only on the western versant in the southern part (Core Area 6). This distribution pattern is most likely an artifact of inadequate sampling on the western slope of the mountain range, much of which is in Myanmar.
Diagnosis. Adults of this species ( ) and meadows with scattered grasses and shrubs, at the edges of agricultural fields, including wet and dry rice paddies, under clods of soil in recently tilled fields and on open banks of streams, and in these same habitats at night, when beetles were found active on bare substrate. They were also collected under debris and in leaf litter in deciduous forests and also in crevices between stones in a talus slope. Members of this species were found at elevations ranging from 1515 to 3000 m, syntopic with adults of A. birmana, A. chalciope, A. davidi, A. lucidissima, A. shaanxiensis, and A. sikkimensis at one or more sites.
Geographical distribution within the Gaoligong Shan. Fig. 11d. We examined a total of 34 specimens (18 males and 16 females) from the following localities:  Members of this species were collected from the northern to the southern parts of the study area (Core Areas 2, 3, 5 and 6), but they were found only on the eastern side of the mountain range in northern half of the study area (Core Areas 2 and 3), on both side in the central part (Core Areas 3 and 4) and only on the western versant in the southern part (Core Area 6). This distribution pattern is most likely an artifact of inadequate sampling on the western slope of the mountain range in the north, some of which is in Myanmar.
Overall geographical distribution. Fig. 27. This species has been recorded from China (Gansu, Hubei, Shaanxi, Sichuan and Yunnan Provinces), Myanmar (extreme north) and Taiwan. Its occurrence in the study area represents the southwestern limit of its known geographical range. Diagnosis. Adults of this species (Fig. 12) can be distinguished from those of all other species in the region by the following combination of character states: body length tarsomere 5 of hind tarsi with two or (in a few specimens) three pairs of setae ventrally (Fig. 6b); last abdominal sternite of male with one pair (Fig.5e) and female with two pairs (Fig.5c) of setiferous punctures near hind margin; male aedeagus with median lobe not or only slightly broader in apical one-third than more basally, apical lamella longer, narrowly rounded apically and with sides more distinctly convergent apically (Fig. 12c), sclerites of internal sac with form as in Fig. 7c-d.

Amara (Amara) shaanxiensis
Habitat distribution. Specimens of this species were collected in daytime from under stones and other cover in open roadside areas (Figs 22a, 25b), meadows and marshy areas with scattered grasses and shrubs, at the edges of agricultural fields, including wet and dry rice paddies and on open banks of streams, and in these same habitats at night, when beetles were found active on bare substrate. They were also collected under debris in daytime and on the surface of leaf litter at night in deciduous forests. Members of this species were found at elevations ranging from 1837 to 3000 m, syntopic with adults of A. birmana, A. chalciope, A. davidi, A. lucidissima, A. pingxiangi, A. sikkimensis and A. silvestrii at one or more sites.
Geographical distribution within the Gaoligong Shan. Fig. 12d. We examined a total of 88 specimens (36 males and 52 females) from the following localities: Members of this species were collected in both the northern and southern parts of the study area (Core Areas 2, 5, 6 and 7), but not in the central part (Core Area 3). This gap in distribution is most likely an artifact of inadequate sampling and not a real disjunction.

Amara (Pseudoamara) birmana
Diagnosis. Adults of this species (Fig. 13) can be distinguished from those of all other species in the region by the following combination of character states: body length 6.5-7.5 mm; dorsal surface with distinct metallic copper or bronze reflection, non-metallic black in very few specimens, at least femora and outer antennomeres dark (piceous to black); elytral microscuplture comprised of distinctly isodiametric meshes in both males and females (more deeply impressed in females than in males); pronotum (Fig. 13a) more distinctly narrowed anteriorly than basally, anterior margin clearly narrower than posterior margin, lateral margins more or less evenly rounded from apical to basal angle, anterior angles not or only faintly and broadly projected anteriorly beyond anterior margin, posterior angles narrowly rounded, basal impressions deeply foveate but small in diameter, outer basal impressions not distinctly delimited laterally by a broad convexity; elytra without evident sub-basal depressions, parascutellar pore puncture absent, elytral striae distinct throughout but only shallowly impressed in most individuals; medial protibial spurs simple; metatibiae of males without a brush-like patch of setae medially in the apical half; tarsomere 5 of hind tarsi with two or (in a few specimens) three pairs of setae ventrally (Fig. 6b); last abdominal sternite of male with one pair (Fig.5e) and female with two pairs (Fig.5c) of setiferous punctures near hind margin; male aedeagus with apical third of median lobe about as broad as middle third, apical hook of right paramere smaller and closer to apex (Fig. 8a).
Habitat distribution. Specimens of this species were collected, often in great abundance, in daytime from under stones and other cover in open roadside areas (Figs 22a, 25a) and waste areas around human settlements (Figs 23a, 25b) with scattered grasses and shrubs, at the edges of agricultural fields and on open banks of streams, and in these same habitats at night, when beetles were found active on bare substrate. They were also collected under rotting logs on a deciduous forest floor. Members of this species were found at elevations ranging from 1590 to 3150 m, syntopic with adults of A. chalciope, A. davidi, A. dissimilis, A. lucidissima, A. pingxiangi, A. shaanxiensis, A. sikkimensis and A. silvestrii at one or more sites.
Geographical distribution within the Gaoligong Shan. Fig. 13d. We examined a total of 244 specimens (126 males and 118 females) from the following localities: Longling County: Longjiang Township (small stream along road at 1. Members of this species were collected only in the southern half of the study area (Core Areas 4, 5, 6 and 7), on both eastern and western slopes of the mountain range.

Amara (Xenocelia) sikkimensis
Diagnosis. Adults of this species (Fig. 14) can be distinguished from those of all other species in the region by the following combination of character states: body length 7-8 mm; dorsal surface dark piceous; pronotum with both inner and outer basal impressions deeply impressed; elytra with parascutellar pore puncture absent; medial protibial spurs simple; tarsomere 5 of hind tarsi with two or (in a few specimens) three pairs of setae ventrally (Fig. 6b); last abdominal sternite of both male (Fig.5d) and female ( Fig.5c) with two pairs of setiferous punctures near hind margin (second seta absent from one side in a few males for total of three setae). Habitat distribution. Specimens of this species were collected in daytime from under stones and other cover in open roadside areas (Fig. 23b) and other waste areas around human settlements (Fig. 23a) with scattered grasses and shrubs, at the edges of agricultural fields, and on open rocky, graveled and sandy banks of streams, and in these same habitats at night, when beetles were found active on bare substrate. They were especially conspicuous on open sandy beaches at night. Members of this species were found at elevations ranging from 1175 to 2800 m, syntopic with adults of A. birmana, A. chalciope, A. davidi, A. dissimilis, A. latithorax, A. lucidissima, A. shaanxiensis and A. silvestrii at one or more sites.
Geographical distribution within the Gaoligong Shan. Fig. 14d. We examined a total of 164 specimens (92 males and 72 females) from the following localities: Members of this species were collected from the northern to the southern parts of the study area (Core Areas 1, 2, 3, 5 and 6), but they were found only on the western side of the mountain range in the southern part (Core Area 6). This distribution pattern may be an artifact of inadequate sampling on the eastern slope of the mountain range in the south.
Overall geographical distribution. Fig. 27. This species has been recorded from Bhutan, China (Gansu, Sichuan and Yunnan Provinces and Xizang Autonomous Region), India (Assam, Himachal Pradesh, Kashmir and Jammu, Sikkim and Uttar Pradesh), Nepal and Pakistan (northern). Its occurrence in the study area represents the southern limit of its known geographical range. Diagnosis. Adults of this species can be distinguished from those of all other species in the region by the following combination of character states: body length 8.5-9.0 mm; dorsal surface black, with very faint metallic blue or green metallic reflection in most individuals, more vivid (as in Fig. 15a) in or lacking from a few specimens, at least femora and outer antennomeres dark (piceous to black); pronotum (Fig. 15a) only slightly narrowed anteriorly with anterior margin nearly straight and clearly narrower than posterior margin, without or with only very slightly projected anterior angles, posterior angles distinctly rounded (narrowly so in some individuals), slightly to moderately obtuse, pronotal base moderately coarsely punctate, outer basal impressions either not sharply delimited laterally by raised areas or, if so, then the raised area broader; elytra elytra with slight sub-basal depressions centered on striae 6 (visible on right elytron in Fig. 15a), also on striae 4 and/or 5 in some individuals, parascutellar pore puncture absent; medial protibial spurs simple; tarsomere 5 of hind tarsi with two or (in a few specimens) three pairs of setae ventrally (Fig. 6b); last abdominal sternite of male with one pair (Fig.5e) and female with two pairs (Fig.5c) of setiferous punctures near hind margin. Habitat distribution. Specimens of this species were collected in daytime from under stones and other cover in open roadside areas (Figs 22b, 23b) and meadows with scattered grasses and shrubs, at the edges of agricultural fields, including wet and dry rice paddies and on open sandy banks of streams, and in these same habitats at night, when beetles were found active on bare substrate. Members of this species were found at elevations ranging from 1195 to 2022 m, syntopic with adults of A. chalciope, A. congrua, A. dissimilis, A. lucidissima and A. sikkimensis at one or more sites.

Amara (Harpaloamara) latithorax
Geographical distribution within the Gaoligong Shan. Fig. 15d. We examined a total of 37 specimens (12 males and 25females) from the following localities:  Members of this species were collected only in the northern half of the study area (Core Areas 1, 2 and 3), on both sides of the mountain range (Core Areas 1 and 2).

Amara (Bradytus) chalciope (Bates, 1891) http://species-id.net/wiki/Amara_chalciope
Diagnosis. Adults of this species (Fig. 16) can be distinguished from those of all other species in the region by the following combination of character states: body length 7.5-9.0 mm; dorsal surface dark with distinct metallic blue-green reflection in most specimens, non-metallic black in a few specimens, at least femora and outer antennomeres dark (piceous to black); elytral microsculpture comprised of isodiametric meshes, faintly impressed or nearly effaced in males, deeply impressed and distinct in females; pronotum ( Fig. 16a) with lateral margins straight or faintly to distinctly sinuate just anterior to basal angles, rounded near middle, less rounded or nearly straight also in anterior one-third in most specimens, anterior angles distinctly and narrowly projected anteriorly beyond anterior margin, lateral explanation distinctly broader basally, outer basal impressions indistinct from lateral groove in most specimens, punctation of base extended anteriorly along sides to pronotal mid-length; elytra with parascutellar pore puncture absent; medial protibial spurs simple; metatibia of male without brush-like setae medially in the apical half; tarsomere 5 of hind tarsi with two or (in a few specimens) three pairs of setae ventrally (Fig. 6b); last abdominal sternite of male with one pair (Fig.5e) and female with two pairs (Fig.5c) of setiferous punctures near hind margin. Habitat distribution. Specimens of this species were collected in daytime from under stones and other cover in open roadside areas (Figs 24b, 25a, 26a), particularly on bare granitic sand substrates on roadcuts, landslides, stream banks, flood outwash flats and open slopes above treeline (Fig. 24a), and in these same habitats at night, when beetles were found active on bare substrate. Members of this species were found at elevations ranging from 1500 to 3611 m (most abundantly between 2500 and 3200 m), and syntopic with adults of A. birmana, A. dissimilis, A. elegantula, A. latithorax, A. lucidissima, A. shaanxiensis, A. sikkimensis, A. silvestrii at one or more sites.
Geographical distribution within the Gaoligong Shan. Fig. 16d. We examined a total of 634 specimens (296 males and 338 females) from the following localities:   This is the only species recorded from all seven Core Areas in the Gaoligong Shan region; but in the southern half of the study area, it is restricted to only the highest elevations, where members are found mainly on the passes over the crest of the mountain range and on the slopes just below the passes on both sides.

Amara (Bradytus) dissimilis
Diagnosis. Adults of this species (Fig. 17) can be distinguished from those of all other species in the region by the following combination of character states: body length 7.7-8.7 mm; dorsal surface dark brown to black, without or with only very faint metallic green reflection, at least femora and outer antennomeres dark (piceous to black); elytral microscuplture comprised of distinctly isodiametric meshes in both males and females (more deeply impressed in females than in males); pronotum (Fig. 17a) dis-tinctly narrowed anteriorly, with anterior margin clearly narrower than the hind margin, lateral margins more or less evenly rounded from apical to basal angle, anterior angles slightly projected anteriorly beyond anterior margin, posterior angles obtusely angulate and slightly denticulate, basal impressions broadly and deeply foveate, outer basal impression distinctly delimited laterally by a broad convexity; elytra without evident sub-basal depressions, pore puncture absent, elytral striae distinct throughout and deeply impressed; medial protibial spurs simple; metatibiae of males with a brush-like patch of setae medially in the apical half; tarsomere 5 of hind tarsi with two or (in a few specimens) three pairs of setae ventrally (Fig. 6b); last abdominal sternite of male with one pair (Fig.5e) and female with two pairs (Fig.5c) of setiferous punctures near hind margin. Habitat distribution. Specimens of this species were collected in daytime from under stones and other cover in open roadside areas (Fig. 24b) and other waste areas (Fig. 22a) around human settlements with scattered grasses and shrubs, at the edges of meadows and agricultural fields, and on open rocky banks of streams, and in these same habitats at night, when beetles were found active on bare substrate. Members of this species were found at elevations ranging from 1500 to 3611 m (most abundantly between 1500 and 3150 m), and syntopic with adults of A. birmana, A. chalciope, A. latithorax, A. lucidissima, A. pingshiangi, A. sikkimensis and A. silvestrii at one or more sites.
Geographical distribution within the Gaoligong Shan. Fig. 17d. We examined a total of 14 specimens (7 males and 7 females) from the following localities: Fugong County: Lumadeng Township ( This species was recorded from all but one Core Area (Core Area 5) in the Gaoligong Shan region. In the southern half of the study area, it is restricted to only the highest elevations, where members are found mainly on the passes over the crest of the mountain range.
Overall geographical distribution. Fig. 27. This species has been recorded from Gansu, Qinghai, Shaanxi, Sichuan and Yunnan Provinces and Xizang Autonomous Region in China. Its occurrence in the study area represents the southern limit of its known geographical range.
Diagnosis. Adults of this species (Fig. 18) can be distinguished from those of all other species in the region by the following combination of character states: body length 7.0-7.5 mm; dorsal surface dark with distinct metallic blue-green reflection in most specimens, non-metallic black in a few specimens, at least femora and outer antennomeres dark (piceous to black); elytral microsculpture effaced or nearly so in both males and females; pronotum ( Fig. 18a) with lateral margins straight or faintly to distinctly sinuate just anterior to basal angles, rounded near middle, less rounded or nearly straight also in anterior one-third in most specimens, anterior angles distinctly and narrowly projected anteriorly beyond anterior margin, lateral explanation narrow throughout, outer basal impressions foveate and distinct from lateral groove, punctation of base not extended anteriorly along sides beyond basal one-third; elytra with parascutellar pore puncture absent; medial protibial spurs simple; tarsomere 5 of hind tarsi with two or (in a few specimens) three pairs of setae ventrally (Fig. 6b); last abdominal sternite of male with one pair (Fig.5e) and female with two pairs (Fig.5c) of setiferous punctures near hind margin; male aedeagus with apical third of median lobe about as broad as middle third, apical hook of right paramere smaller and closer to apex (Fig. 8a).
Habitat distribution. Specimens of this species were collected in daytime from under stones and other cover in open roadside areas near the crest of the mountain range (Fig. 26a), on the rocky heath tundra in areas with scattered vegetation, and on stabilized scree slopes between persistent snow patches in glacial cirques (Fig. 26b). At night, specimens were found in these same areas active on the bare substrate. Specimens were found at elevations ranging from 3350 to 4000 m, the highest sites sampled. The only other Amara species members of which were found syntopic with those of A. elegantula was A. chalciope, with adults of both species found together at only one site at an elevation of 3365 m (Fig. 26a), near the lower altitudinal limit of the former and the upper altitudinal limit of the latter.
Geographical distribution within the Gaoligong Shan. Fig. 18d. We examined a total of 60 specimens (30 males and 30 females) from the following locali-  prised of distinctly transverse meshes in both males and females (more transverse and less deeply impressed in males than in females); pronotum (Fig.19a) only slightly narrower anteriorly than basally, anterior margin almost as wide as posterior margin, lateral margins more or less evenly rounded from apical to basal angle, anterior angles slightly projected anteriorly beyond anterior margin, posterior angles sharp, not rounded, outer basal impressions sharply delimited laterally by narrow, slightly oblique raised (but not carinate) areas, pronotal base very coarsely punctate; elytra with parascutellar pore puncture absent; medial protibial spurs simple; metatibia of male with brush-like setae medially in the apical half; tarsomere 5 of hind tarsi with two or (in a few specimens) three pairs of setae ventrally (Fig. 6b); last abdominal sternite of male with one pair (Fig. 5e) and female with two pairs (Fig. 5c) of setiferous punctures near hind margin.
Habitat distribution. Specimens of this species were collected in daytime from under stones on the open bank of a small stream at an elevation of 1740 m and at night on wet stones along a roadside at 1515 m elevation. The only other Amara species members of which were found syntopic with those of A. simplicidens was A. lucidissima, with adults of both species found together at the 1740 m site.
Geographical distribution within the Gaoligong Shan. Fig. 19d. We examined a total of 2 specimens (1 male and 1 female) from the following localities: This species was recorded only from the western slope of the southern part of the study area (Core Area 6).

Amara (Bradytus) pingshiangi
Diagnosis. Adults of this species (Fig. 20) can be distinguished from those of all other species in the region by the following combination of character states: body length 11-13 mm, body form stout; dorsal surface dark piceous, at least femora and outer antennomeres dark (piceous to black); pronotum with lateral margin markedly rounded,pronotal base punctate, lateral areas in basal half and near anterior margin also punctuate in most specimens; elytra with parascutellar pore puncture absent; me-dial protibial spurs simple; tarsomere 5 of hind tarsi with five or six pairs of setae ventrally (Fig. 6a); last abdominal sternite of male with one pair (Fig.5e) and female with two pairs (Fig.5c) of setiferous punctures near hind margin. Habitat distribution. Specimens of this species were collected only at night, active on the ground in marshy meadow margin areas (Fig. 25b) near forest edges, at elevations ranging from 1515 to 2010 m, and syntopic with adults of A. birmana, A. dissimilis and A. shaanxiensis at one or more sites.
Geographical distribution within the Gaoligong Shan. Fig. 20d. We examined a total of 3 specimens (2 males and 1 female) from the following localities: Gongshan County: Cikai Township (27.74939°/98.66453°, 1515(27.74939°/98.66453°, m, 25 Sep. 2002 Members of this species were collected at only two sites, one in the northeastern part (Core Area 2) and other in the southwestern part (Core Area 6) of the study area, but not in intervening areas. This gap in distribution is most likely an artifact of inadequate sampling and not a real disjunction.

Amara (Reductocelia) lucidissima
Diagnosis. Adults of this species (Fig. 21) can be distinguished from those of all other species in the region by the following combination of character states: body length 6.5-8.0 mm; dorsal surface light-brown to brownish black, without metallic reflection, entire legs and antennae pale; elytra with parascutellar pore puncture absent; medial protibial spurs simple; tarsomere 5 of hind tarsi with two or (in a few specimens) three pairs of setae ventrally (Fig. 6b); last abdominal sternite of male with one pair (Fig.5e) and female with two pairs (Fig.5c) of setiferous punctures near hind margin; male aedeagus with apical third of median lobe broader than middle third, apical hook of right paramere large and slightly subapical (Fig. 8a). Habitat distribution. Specimens of this species were collected, often in great abundance, in daytime from under stones and other cover in open roadside areas and waste areas (Fig. 22a) around human settlements with scattered grasses and shrubs, at       This species was recorded from the southern two-thirds of the study area (Core Areas 2,4, 5, 6 and 7), on both eastern and western slopes of the mountain range.
Overall geographical distribution. Fig. 27. This species has been recorded from China (Fujian, Hubei, Sichuan, Yunnan, and Zhejiang Provinces) and Taiwan. Its occurrence in the study area represents the western limit of its known geographical range.

Discussion
Although the Gaoligong Shan region is at the heart of one of the world's biodiversity hotspots (Myers et al. 2000), this area is near the southern limit of the geographical range of genus Amara in Asia; and so it is not surprising that species diversity there is less than in comparable areas farther north. Of the 13 species we recorded from the area based on material from our ten years of sampling plus additional records from collections (see list in Materials and Methods section above), none of these species are new to science or endemic to the area. Nonetheless, the composition of the Amara fauna of the area is of interest on several levels.
Broad geographical distribution patterns. The overall geographical ranges of the 13 species, superimposed on one another, are graphically approximated in Fig. 27. Among the geographical ranges of these species, three general range patterns are apparent. The first pattern includes seven species (A. congrua, A. davidi, A. lucidissima, A. pingshiangi, A. shaanxiensis, A. sikkimensis and A. simplicidens), more or less broadly distributed in China and eastern Asia, but all of which have their western range limits at or near the Gaoligong Shan region. Two of these, A. congrua and A. simplicidens, have ranges that extend east and north to Japan and the Russian Far East, as well as across most of China east of the study area. Strangely, members of these two species were among the least frequently encountered Amara in the area during our study. The ranges of four species with eastern distributional ranges, A. congrua, A. simplicidens, A. pingshiangi and A. lucidissima, include Fujian Province in China. There are gaps in the known distributions of all of these species between the study area and Fujian, and inadequate sampling is likely the cause of these apparent gaps. For three species, A. congrua, A. lucidissima and A. silvestrii, known geographical ranges also include Taiwan. Both A. congrua and A. lucidissima are also known from Fujian, right across the South China Sea from Taiwan, a disjunction of only about 250 to 400 km, depending on localities compared. The nearest Taiwanese localities for A. silvestrii are more than 1400 km distant from the nearest mainland sites, in Shaanxi Province, and this may represent a real and significant range disjunction. The remaining species included among the class of eastern patterns, A. shaanxiensis, has the most restricted known geographical distribution, recorded only from Yunnan and from Shaanxi Province, but it likely also occurs in intervening areas in along the southern edge of the Qinghai-Xizang Plateau in Sichuan and Gansu Provinces.
The second general geographical range pattern includes two species, A. elegantula and A. latithorax, with geographical ranges that include only the Himalayan region immediately to the west and the Gaoligong Shan region, where they reach their eastern distributional limit. Amara elegantula ranges as far west as eastern Nepal and adjacent parts of Xizang Autonomous Region (Tibet), and the range of A. latithorax also extends west to Nepal, but apparently only on the southern slope of the Himalaya (i.e., it has not been recorded from the northern side of that range). The third general range pattern includes the remaining four species, A. birmana, A. chalciope, A. dissimilis and A. sikkimensis. The geographical distributions of each of these species include the Gaoligong Shan region and areas of varied distance to both the northwest and the northeast along the Himalayan range and the southern edge of the Qinghai-Xizang Plateau, respectively. Of these, A. sikkimensis has the broadest distribution, extended from northen Pakistan in the west to Gansu Province in the east. The known range of A. chalciope extends from Bhutan and Xizang Autonomous Region in the west to Sichuan in the east, with a significantly disjunct occurrence also in Fujian Province in southeastern China. Populations currently included under this name actually may represent a complex of species, a solid understanding of which will require additional study. The known range of A. dissimilis extends from Xizhang in the northwest to Shaanxi in the northeast and actually includes parts of the Qinghai-Xizang Plateau itself in southern Qinghai Province. Finally, A. birmana has the most restricted range of the species with this pattern, known only from northeastern India and northern Myanmar in the west to Sichuan in the east.
On first glance, the observed diversity of Amara species in the study area appears to be due simply to an overlap of faunal elements from both the east and the west. Certainly several of the species with broad distributions in large parts of eastern Asia (e.g., A. congrua and A. simplicidens) likely have their origins in regions to the northeast and so their occurrence in the study area is likely the results of range expansion into the region. However, even a casual look at the majority of range patterns illustrated in Fig. 27 tempts us to suggest that the Gaoligong Shan region, as a core part of the Hengduan Mountains System, may have served as an area of origin for at least part of the Amara fauna which now also occupies the Himalayan Ranges and southern edge of the Qinghai-Xizang Plateau to the west and east, respectively. The Hengduan Mountains date their origins to the late Mesozoic, whereas the uplift of the Himalayan Ranges and Qinghai-Xizang Plateau began later, in the early Cenozoic (Chaplin 2006). So this region may have been an area of differentiation, speciation and origin of montane elements from which, rather than to which, at least some of the species now ranging more broadly in the region subsequently spread. However, an understanding of phylogenetic relationships among the Eurasian and Oriental Amara species is required in order to test this hypothesis, and such an analysis has not yet been undertaken. Comparative DNA sequence data in particular should be highly informative for resolving these relationships. Schmidt et al. (2012) provided distributional and molecular phylogenetic evidence that together support a "Tibetan origin" for the Himalayan endemic Ethira clade of Pterostichini, rather than an origin by dispersal either from western Asia or from mountainous areas to the east of the Himalaya, as we suggest here for Amara. However, because they could not determine the sister group of the Ethira clade from their analysis, it remains unclear whether more inclusive (i.e., older, more basal) relationships are with some element of the pterostichine fauna of the temperate north (as they suggest) or not. Pterostichine material from the Gaoligong Shan inventory project is currently under study, and it will be interesting to see if this material provides any new insights into the origins of that element of the present faunas of the Himalayan Ranges and southern edge of the Qinghai-Xizang Plateau.
Regional geographical and altitudinal distribution patterns. Within the Gaoligong Shan study area, most of the species represented are broadly distributed, both geographically and altitudinally. This is not surprising given the shared preferences of their members for open and disturbed habitats. Such areas are abundant in the lowlands, most often associated with agriculture and human habitation. They are also abundant at all elevations within in the Gaoligong Shan itself, whether in naturally open alpine areas above tree line or in open areas along streams, on flood outwash flats or stabilized landslides, or in open sites created by humans, such as along road cuts, in forest clearcuts and previously burned areas and around all forms of human settlement and activity. What is perhaps unexpected is that a few of the species are quite restricted in their geographical and altitudinal ranges within the study area.
The chart in Fig. 28 summarizes the recorded regional distributions of the species with respect to our project-designated Core Areas; and the recorded altitudinal ranges for each species are shown in Fig. 29. Only A. chalciope is recorded from all seven Core Areas, and this species also shows the broadest altitudinal range (from 1500 to just over 3600 m). Amara dissimilis is recorded from six of the Core Areas (not yet recorded from Core Area 5) and also has a broad altitudinal range (from 1515 to 3150 m). Two species, A. silvestrii and A. sikkimensis, are recorded from five of the Core Areas, including both the northernmost and southernmost, so they are likely to be found in the other Core Areas with additional sampling. Both species also occupy broad altitudinal ranges (from 1515 to 3000 m and from 1175 to 2800 m, respectively). Four species have been recorded from fewer Core Areas but nonetheless are likely to be found more widely in the region with additional sampling in gap areas in their ranges. Amara davidi has been recorded from three Core Areas (1, 6 and 7), A. shaanxiensis from four (2, 5, 6 and 7), A. pingshiangi from two (2 and 6) and A. congrua from four (2, 3, 5 and 6). Among these, A. shaanxiensis has the broadest recorded altitudinal range (from just over 1800 to 3000 m) and A. davidi and A. pingshiangi the narrowest (from 2020 to 2440 m and from 1515 to 2010 m, respectively). Amara congrua has a moderately broad recorded altitudinal range (from 892 to 2000 m), including the lowest elevation at which any Amara species has been recorded in the study area. The five species not yet mentioned all have geographical and, in some cases, also altitudinal ranges that are restricted to at least some extent. Among these, A. lucidissima is the most widespread,  both geographically (Core Areas 3-7) and altitudinally (from 1185 to 3140 m); and because it has been locally abundant wherever it has been found, the absence of records from the northern Core Areas (1 and 2) is significant. Similarly, Amara birmana has been recorded only from the southern half of the study area (Core Areas 4-7), at elevations ranging from 1590 to 3150 m, and this is likely a true measure of its actual distribution in the region. Two species, A. elegantula and A. latithorax, have been recorded only from the northern part of the study area (in Core Areas 1 and 2 and 1-3, respectively). However, these two differ markedly in their altitudinal ranges, with A. latithorax recorded at elevations ranging from about 1200 to 2000 m and A. elegantula found only at elevations ranging from 3350 to at least 4000 m. For A. elegantula, a geographical range restricted to the north is expected, given its restricted high-elevation altitudinal range and the physiography of the study area, with virtually all contiguous areas above 3300 m found in the north. However, we find the restricted northern distribution of A. latithorax surpising, given that its altitudinal range requirements seemingly could be met virtually anywhere along the length of the Gaoligong Shan. The remaining species, A. simplicidens, has been recorded only from Core Area 6 in the southwestern part of the study area and only at relatively low elevations (from 1515 to 1740 m). This is somewhat surprising given that the overall geographical range of this species is so large, extended eastward all the way to Japan and the Russian Far East.
A comparison of recorded diversity for Amara species among the seven Core Areas (Fig. 28) shows that all areas are occupied by at least five species, with highest diversity in Core Area 6 (with 11 of the 13 species), second highest in Core Area 2 (with 9 species) and lowest recorded diversity in Core Area 4 (which is also by far the smallest Core Area). Core Areas 1 and 2 uniquely share one species, A. elegantula, and Core Areas 1-3 together are uniquely occupied two species (A. elegantula and A. latithorax). Core areas 3-7 together are uniquely occupied by three species, A. birmana, A. lucidissima and A. simplicidens; and Core Areas 4-7 together uniquely include two of these, A. birmana and A. simplicidens. Only Core Area 6 has a species, namely A. simplicidens, not shared with any other Core Area. Consequently, but perhaps not surprisingly, the northern and southern extremes of the study area (Core Areas 1 and 2 in the north and 4-7 in the south) have the most distinctive Amara faunas, with Core Area 3 apparently representing a region of faunal transition.
With respect to the altitudinal distribution of the Amara fauna of the study area (Fig. 29), several points can be made. Highest species diversity is concentrated at about 2000 m in elevation, with 11 of the 13 species recorded from that elevation. Only A. elegantula and A. simplicidens do not occur at that elevation, the former only far above that level, the latter only below it. Three species, A. congrua, A. latithorax and A. pingshiangi reach their upper altitudinal limit at about this level, and one, A. davidi, reaches its lower limit. The altitudinal ranges of only four species (A. congrua, A. latithorax, A. lucidissima and A. sikkimensis) extend below about 1200 m, and those of only two species (A. chalciope and A. elegantula) include areas above 3200 m. It could be quite informative to monitor future changes in the altitudinal ranges of these species with respect to the baseline data recorded here as one measure of climate change.
Syntopy of species in the regional fauna. Because virtually all Amara species prefer habitats that are open and more or less disturbed, either by natural processes or through human activities, and because there is so much overlap in both the geo-graphical and altitudinal ranges of species represented in the study area, it is not at all surprising to find that specimens of several different species can be found together at the same site in the same habitat (i.e., syntopic). This co-occurrence of species at sites in the region is summarized in Fig. 30. During fieldwork for this project, it was not uncommon to find several species, up to seven in at least one instance, together at the same time at the site. Four species, A. birmana, A. chalciope, A. lucidissima and A. sikkimensis, have been recorded syntopic with eight other species in one or more sites; three species, A. dissimilis, A. shaanxiensis and A. silvestrii, have been found syntopic with seven other species; and A. davidi, A. latithorax and A. pingshiangi have been recorded syntopic with four, five and three other species each, respectively. Members of these ten species are often found together, in various combinations, at different sites in the study area, although not one of them co-occurs with all the others. By contrast, three species have been found syntopic with just one other species. Amara congrua adults have been found together with those of A. latithorax one time (in Shanga, Fugong County). Members of A. simplicidens have been found just once with those of A. lucidissima (near Datang Village, Tengchong County). Finally, adults of A. elegantula have been found twice with those of A. chalciope twice, both at sites around Heipu Yakou (Pass) on the Gongshan-Dulong Road at an elevation of 3365 m, where the altitudinal ranges of these species overlap narrowly. It is possible that A. congrua and Figure 30. Chart illustrating the co-occurence (syntopy) of Amara species in samples from the same habitats and at the same sites in the Gaoligong Shan region.
A. simplicidens will be found co-occurring more broadly with the same species or with other species in the future because the geographical and/or altitudinal ranges of each are within the ranges of other species, whereas the restricted geographical and altitudinal ranges of A. elegantula should preclude any but the already observed co-occurrence with A. chalciope.
In the future, it will be interesting to compare and contrast both the broad and regional geographical distributions and the altitudinal and ecological range patterns seen in other carabid groups represented in the area with those found among the Amara species and reported here.