Trechus (Trechus) mingguangensis Deuve and Liang, 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 : 389-391

Trechus (Trechus) mingguangensis Deuve and Liang , sp. nov.

( Figs. 19 , 41b , 46–48 )

TYPE MATERIAL.— Holotype, a male, in IOZ, labeled: “CASENT 1038692”/ “ CHINA, Yunnan, Tengchong County, Mingguang Township, Eighth Boundary Post Pass , N25.80984° / E98.62084°, 2287 m, 23 May 2006,”/ “Stop # DHK-2006-037A, D.H. Kavanaugh , R.L. Brett, X.P. Wang & D.Z.Dong collectors”/ “ HOLOTYPE Trechus mingguangensis Deuve & Liang , sp. nov. designated 2016” [red label] . Paratypes (only 1): a female (in CAS) labeled: “CASENT 1038840”/ “ CHINA, Yunnan, Tengchong County, Mingguang Township , small stream on SW-facing slope below 7.9 airkm N of Zizhi village, 2200 m,”/ “ N25.80314° / E98.62117°, 2200 m, 23 May 2006,”/ “Stop # DHK-2006-038A, D.H. Kavanaugh & D.Z. Dong collectors”/ “ PARATYPE Trechus mingguangensis Deuve & Liang , sp. nov. designated 2016” [yellow label] .

TYPE LOCALITY.— China, Yunnan, Tengchong County, Mingguang Township, Eighth Boundary Post Pass , N25.80314° / E98.62117°, 2287 m .

DERIVATION OF SPECIES NAME.— The species epithet, mingguangensis , is derived from the name of the township in which the type locality is located, Mingguang, and the Latin suffix, -ensis, denoting place.

DIAGNOSIS.— Adults of this species ( Fig. 19a ) can be distinguished from those of all other species in the region by the following combination of character states: size large (BL = 4.5 to 4.8 mm), apterous; body color reddish-brown; tempora glabrous, short and convex; pronotum transverse (ratio PW/PL = 1.40), basal angles acute and sharp; elytra very slightly elongate, striae finely punctate, striae 1 to 4 deeply impressed, stria 5 more faintly impressed, striae 6 to 8 effaced or nearly so, recurrent stria terminated anteriorly at a slight convexity in line with the presumed location of stria 7 apically; two normal discal setae present, inserted next to stria 3, preapical seta present, inserted in a discal position next to stria 3 at apical one-fourth of elytra; median lobe of male aedeagus with a large sagittal aileron, apical lamella long and rectilinear, nearly straight, apex thin, endophallus with copulatory piece poorly defined ( Fig. 19b ).

DESCRIPTION.— Size large, BL = 4.5 to 4.8 mm. Body color dark reddish-brown, shiny, appendages paler, yellowish- or reddish-tan, palpi pale yellow. Body surface smooth, only head capsule faintly alutaceous.

Head. Moderate in size; eyes slightly reduced, moderately convex, but their diameter less than twice as long as tempora, the latter short, moderately convex and glabrous. Frons moderately flattened; frontal furrows deep, curved, prolonged and not attenuated posterior to the eyes. Two pairs of supraorbital setae present, the anterior pair inserted in foveae. Clypeus with four setae. Labrum with six setae, anterior margin distinctly concave. Mentum and submentum not fused but suture between them only faintly impressed. Mentum with medial tooth broad and apically truncate, about one-half the length of the lateral lobes. Submentum with six setae anteriorly. Gula wide. Genae with a single seta ventrally on each side. Antennae short, not quite extended to the basal one-fourth of elytra, male with about 2.5 to 3 antennomeres extended posteriorly beyond basal pronotal margin; antennomeres 2 and 3 about equal in length, antennomere 4 slightly shorter.

Pronotum. Moderately transverse (ratio PW/PL = 1.40), narrowed posteriorly, greatest width anterior to middle; lateral margins widely rounded, straightened only just anterior to basal angles, the latter small, but projected, acute and sharp. Disc convex, smooth and glabrous, median longitudinal impression sharply impressed, not quite extended to anterior margin; basal foveae distinct, subcircular; median basal area with several faint, longitudinal rugulae, delimited laterally by oblique furrows. Basal margin slightly bisinuate, slightly reflexed and oblique laterally, slightly projected medially. Lateral borders of pronotum moderately slender, regular, slightly reflexed, lateral grooves deeply impressed. Single midlateral setae on each side inserted slightly anterior to middle; single basolateral seta on each side, inserted at basal angle.

Elytra. Ovoid, only very slightly elongate, more narrowed basally than apically, humeri distinct but rounded. Disc convex and smooth. Striae very finely punctate, striae 1 to 4 deeply impressed, stria 5 more faintly impressed, striae 6 to 8 effaced or nearly so. Parascutellar striole present. Recurrent stria terminated anteriorly by a slight convexity at the presumed location of stria 7 apically. Basal setiferous pore present at common origin of striae 1 and 2. Two discal setae present and inserted next to stria 3, one at anterior one-fourth and one near middle of elytra. Preapical seta present and inserted in a discal position on interval 3, next to stria 3 in forward position at apical one-fourth of elytra. Umbilicate setal series with setae of humeral group equidistance from each other and setae of median group inserted slightly posterior to middle.

Legs. Relatively short, protibiae with longitudinal furrow. Male protarsomeres 1 and 2 dilated and apicomedially toothed.

Abdomen. Abdominal ventrites glabrous, except for a single paramedial seta on each side, and ventrite VII of males apically with one pair of paramedial setae, of females with four pairs.

Male aedeagus. Median lobe ( Fig. 19b ) only slightly enlarged basally but with a large sagittal aileron present; shaft markedly narrowed at middle and broader subapically; apical lamella long, rectilinear, extremely thin in lateral view; endophallus voluminous but without well-defined sclerites.

HABITAT DISTRIBUTION.— One specimen of this species was found under stones and debris along a roadcut ( Fig. 41b ) through slightly disturbed primary forest of Tsuga , with small, scattered small bamboo thickets; and the other specimen was found under stones along a small stream crossing the road in the same general area. No other trechines were collected in either of these sites, which range in elevation from 2200 to 2287 m.

GEOGRAPHICAL DISTRIBUTION WITHIN THE GAOLIGONG SHAN.— Fig. 19c . We examined a total of 2 specimens, both from Mingguang Township in Tengchong County on the western slope of the southern part of the Gaoligong Shan (see Type material above for exact collection data). Both of these localities are in Core Area 6 .

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

Figures

FIGURE 19. Trechus mingguangensis sp. nov.; a. Dorsal habitus (CASENT1038692). b. Median lobe of aedeagus of male (CASENT1038692), left lateral aspect. c. Map of locality records (red circles) for T. mingguangensis in the Gaoligong Shan region. Scale lines a, b = 0.5 mm, c = 100 km.

FIGURE 41. Photographs of habitats for trechine species in the Gaoligong Shan region. a. Gongshan County, Dulongjiang Township, Dulong Jiang at Elideng village, elevation 1640 m; habitat in which specimens of Trechus indicus Putzeys were collected. b. Tengchong County, Mingguang Township, slope SW of Eighth Boundary Post Pass, elevation 2887 m; habitat in which specimens of Trechus mingguangensis sp. nov. were collected. Photos 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.