Euconnus (Tetramelus) gansuminor Jałoszyński, 2024, sp. nov.
Creators: name: Jałoszyński, Paweł
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Staphylinidae
Euconnus
Euconnus gansuminor

description: Euconnus (Tetramelus) gansuminor sp. nov.
(Figs 17, 26, 77–80)
Material studied. Holotype: ♂ (CHINA: Gansu): “CHINA: Gansu Prov. [CH11-12 a] / Lenglong Ling Mts., pass road 61.5 km / N Honggu, 2875-2900 m, 36°53’11.0’’N, / 102°45’30.8’’E, dry grass steppe and / field edges, under stones, running on / trail, 30.VI.2011, leg. M. Schülke ” [white, printed], “ EUCONNUS / (TETRAMELUS) / tetraspinosus m. / P. Jałoszyński, 2024 / HOLOTYPUS” [red, printed] (MNHB).
Diagnosis. Body dark brown; male metatrochanter distally produced into short and stout subtriangular spine, ventral margin of trochanter distally bent at an obtuse angle; aedeagus in ventral view about twice as long as wide, its ventral plate conspicuously small, elongate and subtriangular with rounded apex, dorsal plate elongate, with sinuate lateral margins strongly converging distally to narrow truncate apex, endophallus in ventral view with two short and curved elongate sclerites of unequal lengths surrounded by membranous folds densely covered with cuticular denticles.
Description. Body of male (Fig. 17) elongate and slender, moderately convex, with long appendages, BL 1.40 mm; cuticle glossy, pigmentation uniformly dark brown, vestiture of setae lighter than cuticle.
Head in dorsal view round, broadest across eyes, HL 0.23 mm, HW 0.23 mm; in lateral view each temple slightly more than 3 times as long as eye; vertex weakly convex and only slightly bulging posterodorsally; frons flattened; supraantennal tubercles small and indistinctly elevated. Eyes small, finely faceted, hardly projecting laterally from head silhouette, in lateral view oval. Punctures on vertex and frons inconspicuous, small and sparse; setae short and sparse, suberect, sparse and short thick bristles present on vertex and tempora. Antennae slender, almost as long as half BL, AnL 0.68 mm; antennomeres 1–2 elongate, 3–8 each about as long as broad, 9 and 10 each weakly transverse, 11 slightly shorter than 9–10 combined, about 1.7 times as long as broad.
Pronotum broadest anterior to middle, PL 0.35 mm, PW 0.28 mm; anterior margin arcuate, lateral margins rounded in anterior half and nearly straight in posterior third, posterior corners slightly obtuse-angled, blunt; posterior margin weakly rounded. Pronotal base with single outer pair of faint pits. Punctures on pronotal disc inconspicuous; setae moderately dense and short, suberect and on sides mixed with thick bristles.
Elytra oval, broadest near middle, EL 0.83 mm, EW 0.53 mm, EI 1.57; basal impressions and humeral calli lacking, elytral apices rounded together. Punctures on elytral disc inconspicuous, superficial; setae similar to those on pronotum, moderately dense and weakly suberect.
Legs long and slender, metatrochanter (Fig. 26) distally produced into short and stout subtriangular spine, ventral margin of trochanter distally bent at an obtuse angle.
Metaventrite with deep oval median impression occupying most of its surface, extending on almost entire length.
Aedeagus (Figs 77–80) stout, AeL 0.38 mm; median lobe in ventral view broadest distally to middle, capsular part distally truncate, ventral plate conspicuously small, elongate and subtriangular with rounded apex, dorsal plate elongate, with sinuate lateral margins strongly converging distally to narrow truncate apex, endophallus in ventral view with two short and curved elongate sclerites of unequal lengths surrounded by membranous folds densely covered with cuticular denticles. Dorsal wall with short setae; parameres slender, each with 3 long subapical setae.
Female. Not known.
Distribution. Central China: Central Gansu.
Etymology. The adjective gansuminor alludes to the locality where this species has been collected (Gansu province) and to the very small body size.
Remarks. This species is the smallest of all Chinese Tetramelus. The metatrochanter in E. gansuminor is nearly identical to those in E. aurilobatus and E. microrufus. Aedeagi of these three species differ remarkably, with only that of E. aurilobatus having large distolateral lobes. Aedeagi of E. gansuminor and E. microrufus show clearly different general shapes, different shapes of both ventral and dorsal plates, and a different arrangement of endophallic structures.
description: Published as part of Jałoszyński, Paweł, 2024, Subgenera Cladoconnus Reitter and Tetramelus Motschulsky of Euconnus Thomson discovered in China (Coleoptera, Staphylinidae, Scydmaeninae), pp. 232-256 in Zootaxa 5514 (3) on pages 248-249, DOI: 10.11646/zootaxa.5514.3.2, http://zenodo.org/record/13849780