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

description: Euconnus (Tetramelus) microrufus sp. nov.
(Figs 18, 27, 81–83)
Material studied. Holotype: ♂ (CHINA: Yunnan): “CHINA: N-Yunnan [C03-12] / Zhongdian Co., pass 28 km ESE Zhong- / dian, devastated primary forest with / young Abies, Larix, Betula, Rhodod., / 27°43.9’ N, / 99°58.2’E, / 3700-3750m, / 22.VIII.2003, leg. M. Schülke ” [white, printed], “ EUCONNUS / (TETRAMELUS) / microrufus m. / P. Jałoszyński, 2024 / HOLOTYPUS” [red, printed] (MNHB).
Diagnosis. Body rufous brown; male metatrochanter distally produced into short and stout subtriangular spine, ventral margin of trochanter distally weakly bent at an obtuse angle; aedeagus in ventral view nearly 3 times as long as wide, its ventral plate about as long as broad, with lateral margins sinuate and strongly converging distally to narrow rounded apex, dorsal plate elongate, with nearly straight lateral margins strongly converging distally to broad truncate apex, endophallus in ventral view with three short elongate sclerites of unequal lengths surrounded by membranous folds densely covered with cuticular denticles.
Description. Body of male (Fig. 18) elongate and slender, moderately convex, with long appendages, BL 1.80 mm; cuticle glossy, pigmentation uniformly rufous brown, vestiture of setae lighter than cuticle.
Head in dorsal view round, broadest at eyes, HL 0.28 mm, HW 0.29 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, indistinctly shorter than half BL, AnL 0.80 mm; antennomeres 1–5 elongate, 6–8 each about as long as broad, 9 and 10 each weakly transverse, 11 slightly shorter than 9–10 combined, about 1.6 times as long as broad.
Pronotum broadest in front of middle, PL 0.45 mm, PW 0.38 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 one 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 distinctly in front of middle, EL 1.08 mm, EW 0.65 mm, EI 1.65; 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. 27) distally produced into short and stout subtriangular spine, ventral margin of trochanter distally weakly bent at an obtuse angle.
Metaventrite with deep oval median impression occupying most of its surface, extending on almost entire length.
Aedeagus (Figs 81–84) slender, AeL 0.55 mm; median lobe in ventral view broadest near middle, distally rapidly narrowing, ventral plate about as long as broad, with lateral margins sinuate and strongly converging distally to narrow rounded apex, dorsal plate elongate, with nearly straight lateral margins strongly converging distally to broad truncate apex, endophallus in ventral view with three short 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. WS China: Yunnan, Diqing Tibetan Autonomous Prefecture.
Etymology. The adjective microrufus refers to the small body size and to reddish-brown pigmentation.
Remarks. As mentioned above, the metatrochanter in E. microrufus is nearly identical to those in E. gansuminor and E. aurilobatus, but the aedeagi of these three species strongly differ. Of these three species, E. gansuminor has the aedeagus most similar to that of E. microrufus. However, all important structures, i.e., the general shape of the median lobe, shapes and proportions of the ventral and dorsal plate, and shape and arrangement of endophallic structures, are clearly different in these two species.
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 249-250, DOI: 10.11646/zootaxa.5514.3.2, http://zenodo.org/record/13849780