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

description: Euconnus (Tetramelus) sinespinosus sp. nov.
(Figs 19, 28, 85–88)
Material studied. Holotype: ♂ (CHINA: Sichuan): “CHINA: N-Sichuan [CH12-24] / pass 35 km NNW Songpan / 32°55’32’’N, 103°25’56’’E, 3600 m, / moist N-slope with Salix and other / shrubs, litter, grass roots & moss / sifted, 11.VIII.2012, leg. M. Schülke ” [white, printed], “ EUCONNUS / (TETRAMELUS) / sinespinosus m. / P. Jałoszyński, 2024 / HOLOTYPUS” [red, printed] (MNHB).
Diagnosis. Body nearly black with distinctly lighter proximal region of antennae and infuscate clubs; male trochanters unmodified; aedeagus in ventral view slightly more than twice as long as wide, its ventral plate much wider than long, with lateral margins weakly concave and strongly converging distally to narrow rounded apex, dorsal plate elongate, with broad subtriangular proximal half and rapidly narrowed long distal portion slightly broadened subapically and with narrow rounded apex, endophallus in ventral view with three long sclerites of unequal lengths, of which two left sclerites are parallel and long, and one right sclerite is much shorter and divergent in relation to left pair, between sclerites endophallic folds covered densely with cuticular denticles.
Description. Body of male (Fig. 19) elongate and slender, moderately convex, with long appendages, BL 1.53 mm; cuticle glossy, pigmentation nearly black with slightly lighter legs and distinctly lighter proximal antennomeres and infuscate clubs, vestiture of setae lighter than cuticle.
Head in dorsal view round, broadest across eyes, HL 0.25 mm, HW 0.25 mm; in lateral view each temple about 1.5 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 0.65 mm; antennomeres 1–3 elongate, 4–8 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 anterior to middle, PL 0.38 mm, PW 0.33 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 small but distinct pits. Punctures on pronotal disc inconspicuous; setae moderately dense and short, suberect and on sides mixed with thick bristles.
Elytra oval, broadest slightly in front of middle, EL 0.90 mm, EW 0.58 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. 28) unmodified.
Metaventrite with deep oval median impression occupying most of its surface, extending on almost entire length.
Aedeagus (Figs 85–88) stout with conspicuously slender apical region, AeL 0.50 mm; median lobe in ventral view broadest distally to middle, distally rapidly narrowing, ventral plate much wider than long, with lateral margins weakly concave and strongly converging distally to narrow rounded apex, dorsal plate elongate, with broad subtriangular proximal half and rapidly narrowed long distal portion slightly broadened subapically and with narrow rounded apex, endophallus in ventral view with three long sclerites of unequal lengths, of which two left sclerites are parallel and long, and one right sclerite is much shorter and divergent in relation to left pair, between sclerites endophallic folds covered densely with cuticular denticles. Dorsal wall lacking setae; parameres slender, each with 3 long subapical setae.
Female. Not known.
Distribution. Central China, NC Sichuan.
Etymology. The adjective sinespinosus is derived from a Latin phrase sine spinae, “without spines,” and refers to the unmodified metatrochanters.
Remarks. Euconnus sinespinosus is the only known Chinese Tetramelus with all trochanters in male unmodified. Its aedeagus is most similar to that of E. mediorufus, but shapes of the ventral and distal plates, as well as arrangement of endophallic structures are clearly different.
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 250-252, DOI: 10.11646/zootaxa.5514.3.2, http://zenodo.org/record/13849780