Agonotrechus Jeannel, 1923

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 : 352-353

Genus Agonotrechus Jeannel, 1923

Agonotrechus Jeannel, 1923:428 .

Paragonotrechus Uéno, 1981:2 .

Bhutanotrechus Uéno, 1977:188 .

TYPE SPECIES.— Trechus birmanicus Bates, 1892 .

DIAGNOSIS.— Adults of this genus ( Figs. 7a – 9a ) can be recognized by the following combination of character states: size medium to large for a trechine (BL = 4.5 to 7.0 mm) members of most species with full hindwings and large, convex eyes, but those of a few species apterous and with eyes reduced in size and/or convexity, some even microphthalmous or nearly anophthalmous; frons flattened, depressed; dorsolateral margin of mandibular scope with a row of small setae aligned as a sparse comb in some members ( Belousov & Kabak 2003); right mandible ( Fig. 16a ) bidentate, the premolar tooth fused with the retinaculum, from which the anterior tooth is distinctly projected and in a forward position and the posterior tooth is absent or flush; left mandible with only a short, subconical, more or less trifid ridge; clypeus with six setae in most members; labium with anterior margin not or only slightly concave; mentum fused with submentum, incompletely in some members; submentum with six setae in most members, but some with eight setae; pronotum little narrowed basally, with lateral explanation distinctly broadened basally in many members; elytra with discal striae varied, from complete to effaced, punctate in many members, parascutellar striole very long in many members; anterior discal seta present in all members and inserted at the basal one-fifth or one-sixth of elytra, middle discal seta present or absent, preapical seta present at or near stria 2 in most members, absent from a very few members; legs slender, protibiae furrowed, the basal two protarsomeres dilated and toothed; abdominal ventrites glabrous except for usual paramedial setae; aedeagus with a spoon-shaped copulatory piece.

TAXONOMIC NOTES.— Members of the first known Agonotrechus species had only the anteri- or discal seta of the elytron inserted at the basal one-fifth or one-sixth. Consequently, this feature was used by Jeannel (1923) to define his new genus. Members of Paragonotrechus Uéno (1981) are very similar and differ only in having a more slender body form and the parascutellar striole very long. Those of Bhutanotrechus Uéno (1977) , described from Bhutan, were distinguished by having the elytral discal striae effaced and a second elytral discal seta (the middle seta) present. The presence of the middle seta is a plesiotypic feature in Trechini , but species with members having two discal setae sometimes have been grouped together or assigned to genus Bhutanotrechus ( Deuve 1992b, 1995). Genus Agonotrechus is really a homogenous group, despite the differences among its members in impression of the elytral discal striae, length of the parascutellar stiole, number of elytral discal setae and size of the eyes, differences in the last feature being associated with differential flight capability. There appears to be no reason to maintain Paragonotrechus and Bhutanotrechus as distinct genera.

The bidentate dentition of the right mandible of Agonotrechus , with the premolar tooth completely fused with retinaculum, distinguishes this group from members of the Stevensius Complex, with which Jeannel (1923, 1928) had grouped it.

GEOGRAPHICAL DISTRIBUTION.— This genus, which at present includes 16 species, is known from the southeastern part of the Palearctic Region and northern edge of the Oriental Region, from Nepal eastward to southern Gansu Province in the north and Myanmar, Vietnam, and Hubei and Shaanxi Provinces; and one species has been described from Japan. The study area is within the previously known range of this genus.

Figures

FIGURE 7. Agonotrechus fugongensis sp. nov.; a. Dorsal habitus (CASENT1019979). b. Median lobe of aedeagus of male (CASENT1019979), left lateral aspect. c. Map of locality records (red circles) for A. fugongensis in the Gaoligong Shan region. Scale lines a, b = 0.5 mm, c = 100 km.

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.