Agonotrechus xiaoheishan Deuve, 2016

Deuve, Thierry, Kavanaugh, David H. & Liang, Hongbin, 2016, Inventory of the Carabid Beetle Fauna of the Gaoligong Mountains, Western Yunnan Province, China: Species of the Tribe Trechini (Coleoptera: Caraboidea), with Descriptions of Four New Genera, One New Subgenus and 19 New Species., Proceedings of the California Academy of Sciences 63 (12), pp. 341-455 : 359-363

Agonotrechus xiaoheishan Deuve and Kavanaugh, sp. nov.

( Figs. 9 , 16a , 44 , 46–48 )

TYPE MATERIAL.— Holotype, a male, in IOZ, labeled: “CASENT 1036866”/ “ CHINA, Yunnan, Longling County, Longjiang Township , Xiaoheishan Forest Reserve, N 24.83671°/ E098.76185°,”/ “ 2067 m, 28 May 2005, Stop# HBL-05-19, H.B. Liang, H.M. Yan & K.J. Gao collectors”/ “ HOLOTYPE Agonotrechus xiaoheishan Deuve & Kavanaugh, sp. nov. designated 2016” [red label] . Paratypes (a total of 13): 2 males and 7 females (in CAS, IOZ, MNHN) labeled same as holotype except first label “CASENT 1036874”, “CASENT 1036875”, “CASENT 1036867”, “CASENT 1036868”, “CASENT 1036869”, “CASENT 1036870”, “CASENT 1036871”, “CASENT 1036872” and “CASENT 1036873”, respectively ; 1 male and 1 female (in CAS) labeled “CASENT 1036863” and “CASENT 1036864”, respectively/ “ CHINA, Yunnan, Longling County, Longjiang Township , Xiaoheishan Forest Reserve, Guchengshan, 2020 m, N24.82888° / E098.76001°,”/ “ 28 May 2005, Stop# 2005-033B, D.H. Kavanaugh , H.B. Liang, D.Z. Dong & J.L. Yang collectors” ; 2 females (in CAS) labeled “CASENT 1031915” and “CASENT 1031916”, respectively/ “ CHINA, Yunnan, Longling County, Longjiang Township , Xiaoheishan Forest Reserve, Guchengshan, 2020 m, N24.82888° / E098.76001°,”/ “ 28 May 2005, Stop# 2005-033C, D.H. Kavanaugh , C.E. Griswold, H.B. Liang, D.Z. Dong, H.M. Yan & K.J. Guo collectors”. All paratypes also bear the following label: “ PARATYPE Agonotrechus xiaoheishan Deuve & Kavanaugh, sp. nov. designated 2016” [yellow label] .

TYPE LOCALITY.— China, Yunnan, Longling County, Longjiang Township , Xiaoheishan Forest Reserve, N 24.83671°/ E098.76185°, 2067 m .

DERIVATION OF SPECIES NAME.— The species epithet, xiaoheishan , is a noun in apposition, derived from the name of the area in which the holotype was collected.

DIAGNOSIS.— Adults of this species ( Fig. 9a ) can be distinguished from those of all other species in the region by the following combination of character states: size medium (BL = 5.3 to 5.7 mm), fully-winged, dorsum piceous to reddish brown and distinctly iridescent; head slender, eyes only moderately projected; clypeus with four setae; mentum and submentum fused, submentum with six setae; mandibles with two or three small setae along the dorsolateral margin of the scrobe; pronotum small and narrow (ratio PW/PL = 1.21), basal angles subrectangular, basal flattened area restricted; midlateral seta inserted at anterior one-fourth, basolateral seta at hind angle; elytra with all discal striae evident, deeply impressed and punctate, however striae 1 to 4 effaced or nearly so near base, parascutellar striole rather long, recurrent stria continuous anteriorly with stria 5, intervals convex, only a single discal seta (anterior seta) present, inserted at basal one-eighth of elytra in stria 3; median lobe of aedeagus of male ( Fig. 9b ) short, with apex bent ventrally and bluntly pointed, endophallus with a spoon-shaped sclerite.

DESCRIPTION.— Size medium, BL = 5.3 to 5.7 mm. Color of dorsum piceous, shiny, iridescent, femora concolorous, tibiae, tarsi, antennae and mandibles paler reddish tan, palpi yellowish tan.

Head. Relatively slender, eyes only moderately projected, but nonetheless convex and with diameter twice length of tempora. Tempora not or only slightly convex, joined to neck region at ca. 120° angle. Frons slightly flattened, with two pairs of supraorbital setae, frontal furrows linear, distinct between the eyes, but effaced posterior to insertion of second supraorbital seta. Clypeus with four setae. Labrum slightly widened apically, apical margin slightly concave. Mandibles sharp, the right mandible ( Fig. 16a ) bidentate with the anterior tooth spaced well forward of the posterior tooth and the left mandible with only a small subtriangular process, also with two or three small setae along the dorsolateral margin of the scrobe. Mentum and submentum fused. Mentum with medial tooth rather broad, with the apex either obtuse or truncate, less than one-half as long as lateral lobes. Submentum with six setae subapically, gula broad. Genae with a single seta ventrally on each side. Antennae long and slender, extended to (in females) or slightly beyond (in males) the middle of the elytra, with five or six antennomeres beyond the pronotal base; antennonmeres 3 and 4 virtually the same length and antennomere 2 slightly shorter.

Pronotum. Relatively small, not or only slightly narrowed basally, only slightly transverse, ratio PW/PL = 1.21, widest at anterior one-third; lateral margins rectilinear in basal half, not sinuate except for a very slight and short inflexion just anterior to the basal angle, which is subrectangular and sharp; pronotal disc smooth, glabrous, moderately convex; median longitudinal impression very fine; basal foveae deep, basal flattened area rather small, delimited laterally by short but deep and oblique furrows. Lateral explanation slender and moderately reflexed in anterior two-thirds, then progressively broader in basal one-third without. Midlateral pair of setae inserted at anterior one-fifth and basolateral pair inserted at hind angles.

Elytra. Convex, large and broad, especially in relation to pronotum, elytral silhouette ovoid, about equally narrowed apically and basally, humeri evident but rounded. All discal striae evident, regular, deeply impressed and punctate, however striae 1 to 4 effaced or nearly so near base, parascutellar striole rather long, recurrent stria continuous anteriorly with discal stria 5, intervals convex, only a single discal seta (anterior seta) present, inserted at basal one-eighth near stria 3. Parascutellar setiferous pore present at base at common origin of discal striae 1 and 2. Anterior discal seta present, inserted at basal one-eighth of elytra in stria 3, which is effaced anterior to that point. Middle discal seta absent. Preapical seta present on interval 3 near stria 2 opposite the anterior edge of the subapical sinuation. Umbilicate setal series with setae of humeral group equidistant for each other and those of median group both inserted posterior to middle of elytra.

Legs. Slender but only moderately long. Protibiae furrowed. Male protarsi with tarsomeres 1 and 2 dilated and apicomedially toothed.

Male aedeagus. Median lobe ( Fig. 9b ) short, with apex bent ventrally and bluntly pointed, endophallus with a spoon-shaped sclerite.

COMMENTS.— Members of this new species are morphologically similar to those of Agonotrechus birmanicus Bates (1892) , described from Kachin State in Myanmar, and Agonotrechus tenuicollis Uéno (1986) , described from eastern Nepal. However, they can be distinguished from members of both of these other species by the following features: pronotum with anterior margin straight, not concave, anterior angles only faintly projected and more broadly rounded, and lateral borders more slender anteriorly and at middle; and apex of the median lobe of the male aedeagus narrower and more curved.

HABITAT DISTRIBUTION.— Members of this species have been found in and under rotting logs in dark, closed-canopy broadleaf evergreen forest ( Fig. 44 ) at elevations ranging from 2020 to 2067 m. Although members of no other Agonotrechus species have been found syntopic with those of A. xiaoheishan , specimens of Trechus indicus were collected in the same samples.

GEOGRAPHICAL DISTRIBUTION WITHIN THE GAOLIGONG SHAN.— Fig. 9c . We examined a total of 14 specimens (4 males and 10 females), all from Xiaoheishan Forest Reserve in the southern part of the Gaoligong Shan (see Type material above for exact collection data) .

This species was recorded only from near the top of the western slope in the southern part of the study area (Core Area 6). Its known geographical range does not overlap with that of any other Agonotrechus species, although A. yunnanus has been recorded from the adjacent Core Area 7 on the eastern slope of the Gaoligong Shan, 13.3 km to the north.

OVERALL GEOGRAPHICAL DISTRIBUTION.— This species currently is known only from the type area in the southern part of the Gaoligong Shan , in western Yunnan Province, China .

Gaoligong Shan in the northern part of Core Area 7. This area is not within the geographical range of any other Agonotrechus species, although A. xiaoheishan has been recorded from the adjacent Core Area 6 on the western slope of the Gaoligong Shan, 13.3 km to the south.

OVERALL GEOGRAPHICAL DISTRIBUTION.— This species currently is known only from the type locality in the southern part of the Gaoligong Shan , in western Yunnan Province, China .

Figures

FIGURE 9. Agonotrechus xiaoheishan sp. nov.; a. Dorsal habitus (CASENT1036866). b. Median lobe of aedeagus of male (CASENT1036866), left lateral aspect. c. Map of locality records (red circles) for A. xiaoheishan in the Gaoligong Shan region. Scale lines a, b = 0.5 mm, c = 100 km.

FIGURE 16. Trechine right mandibles, ventral aspect. a. Agonotrechus xiaoheishan sp. nov. b. Trechus indicus Putzeys with dentition enlarged. c. Trechus gongshanensis sp. nov. d. Trechus shibalicus sp. nov. e. Pseudepaphius gonggaicus Deuve with dentition enlarged (China, Sichuan Province, Moxi Township, NE slope of Gongga Shan). f. Trechepaphiopsis uniporosa sp. nov. with dentition enlarged. g. Epaphiotrechus fortipesoides sp. nov. with dentition enlarged. h. Trechepaphiama gaoligong sp. nov. Scale lines = 0.5 mm.

FIGURE 44. Photograph of habitat for trechine species in the Gaoligong Shan region. Longling County, Longjiang Township, Xiaoheishan Forest Reserve, elevation 2020 m; habitat in which specimens of Agonotrechus xiaoheishan sp. nov. and Trechus indicus Putzeys were collected. Photo by David H. Kavanaugh.

FIGURE 46. Chart showing the representation of trechine species in project-designated Core Areas (see Fig. 3) in the Gaoligong Shan region.

FIGURE 47. Chart illustrating the altitudinal ranges of trechine species represented in the Gaoligong Shan region.

FIGURE. 48. Chart illustrating the co-occurence (syntopy) of trechine species in samples from the same habitats and at the same sites in the Gaoligong Shan region.