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

description: Euconnus (Tetramelus) punctator sp. nov.
(Figs 13, 21, 31–38)
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) / punctator m. / P. Jałoszyński, 2024 / HOLOTYPUS” [red, printed] (MNHB). Paratypes: 8 ♀♀, same data as for holotype (cPJ, MNHB).
Diagnosis. Body rufous brown; male metatrochanter distally produced into long and slender subtriangular spine, ventral margin of trochanter evenly concave in distal half; aedeagus in ventral view about twice as long as wide, its ventral plate wider than long, with sinuate lateral margins and rounded apex, dorsal plate elongate subtriangular with broadly rounded apex, endophallus in ventral view with one elongate and curved sclerite surrounded by membranous folds densely covered with cuticular spines.
Description. Body of male (Fig. 13) elongate and slender, moderately convex, with long appendages, BL 2.04 mm; cuticle glossy, pigmentation uniformly rufous brown, vestiture of setae lighter than cuticle.
Head in dorsal view round, broadest across eyes, HL 0.34 mm, HW 0.31 mm; in lateral view each temple 3 times as long as eye; vertex weakly convex and only slightly bulging posterodorsally; frons flattened; supraantennal tubercles small and indistinctly elevated. Eyes small and 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 0.85 mm; antennomeres 1–5 each elongate (5 weakly so), 6–8 each about as long as broad, 9 and 10 each slightly transverse, 11 distinctly shorter than 9–10 combined, about 1.6 times as long as broad.
Pronotum broadest in front of middle, PL 0.50 mm, PW 0.40 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 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 1.20 mm, EW 0.75 mm, EI 1.60; 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. 21) modified, with long distal spine, ventral margin of trochanter nearly evenly concave in distal half.
Metaventrite with deep oval median impression occupying most of its surface, extending on almost entire length.
Aedeagus (Figs 31–38) stout, AeL 0.50 mm; median lobe in ventral view broadest near distal third, and rapidly narrowed here, ventral plate broader than long, with strongly sinuate lateral margins and narrow rounded apex, dorsal plate elongate subtriangular with lateral margins rounded in apical half, apex broadly rounded; endophallus in ventral view with one elongate and curved sclerite surrounded by membranous folds densely covered with cuticular spines. In lateral view (Fig. 37) short setae can be seen on dorsal wall in subapical region; parameres slender, each with 3 long subapical setae.
Female. Similar to male (with similarly small eyes), lacking metaventral impression and with unmodified metatrochanters. BL 1.85–1.98 mm; HL 0.33–0.35 mm, HW 0.33–0.34 mm, AnL 0.78–0.80 mm; PL 0.45–0.48 mm, PW 0.38–0.40 mm; EL 1.08–1.15 mm, EW 0.69–0.73 mm, EI 1.54–1.64.
Distribution. Central China: NC Sichuan.
Etymology. The name punctator (noun in apposition) alludes to the pointed metatrochanteral spine.
Remarks. The modification of the metatrochanter in this species is most similar to those of T. magnirufus sp. nov. and E. mediorufus sp. nov. described below. In these three species the ventral margin of the metatrochanter is more or less evenly concave in the distal region, and not abruptly bent or nearly straight, as in the remaining Chinese species. Trochanteral modifications are not known in species occurring outside China. Euconnus punctator differs from E. magnirufus in a distinctly smaller body. Aedeagi of these species have a similar shape, but the dorsal plate in E. punctator is elongate with broadly rounded apex, whereas that of E. magnirufus is wider than long and has strongly sinuate lateral margins, so that the apical region is projecting as a narrow subtriangular distomedian lobe. Euconnus mediorufus has a body length similar to that of E. punctator, but its aedeagus has the dorsal plate remarkably narrower than that in E. punctator. These three species share a similar endophallic structure and may be closely related.
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 238-240, DOI: 10.11646/zootaxa.5514.3.2, http://zenodo.org/record/13849780