Omalium schuelkei Shavrin, 2025, sp. nov.
Creators: name: Shavrin, Alexey V.
Publisher: name: Zenodo
Year: 2025
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Staphylinidae
Omalium
Omalium schuelkei

description: 3.4.6. Omalium schuelkei sp. nov.
(Figs 21, 48, 51, 56–58, 62)
Type material examined. Holotype ♂: CHINA: GANSU: ‘CHINA, Gansu, Xinlong | Shan, cca 70 km S | Lanzhou, 2225- | 2380m, 7.VIII.1994 | A. Smetana [C32]’ <printed>, ‘HOLOTYPE | Omalium | schuelkei sp. nov. | Shavrin A.V. des. 2025’ <red, printed> (CNC).
Paratypes (13 ♂♂, 15 ♀♀): CHINA: GANSU: 5 ♂♂ (one specimen dissected), 4 ♀♀ (one specimen dissected): same data as that in the holotype (2 ♂♂, 2 ♀♀: cSh; 3 ♂♂, 3 ♀♀: CNC); 7 ♂♂ (two specimens dissected), 7 ♀♀: ‘ CHINA: Gansu Prov. [CH11-27] | Lenglong Ling Mts., 60 km NNW | Honggu, Jin Sha Gorge, mixed forest | (Picea, Populus, Betula) 36°51´56.9´´N, | 102°38´55.3´´E, litter, moss, mushrooms | sifted, 12.VII.2011, leg. M. Schülke’ <printed>, ‘Museum für Naturkunde | Berlin | Sammlung M. Schülke’ <printed> (3 ♂♂, 2 ♀♀: cSh; 4 ♂♂, 6 ♀♀: cSch); 1 ♀: ‘ CHINA: Gansu province, | XIAHE (= Labrang) env., | 35°11.3´´N 102°30.6´E, | 3043 m (GPS), 19.– 22.VI. | 2005, J. Hájek, D. Král & | J. Růžička leg. [Ch 2]’ <printed>, ‘baited pitfall traps (fish | meat + cheese) with | ethylene glycol. | margin of a wet | coniferous forest ’ <printed>, ‘Museum für Naturkunde | Berlin | Sammlung M. Schülke’ <printed> (cSch); SICHUAN: 1 ♂ (dissected), 2 ♀♀: ‘ CHINA: N-Sichuan [CH12-21] | 49 km N Songpan, road S 301 km 114, | N Gongangling pass, 33°04´31´´N, | 103°42´38´´E, 3230 m, spruce forest, | litter, moss & mushrooms sifted, | 9.VIII.2012, M. Schülke’ <printed>, ‘Museum für Naturkunde | Berlin | Sammlung M. Schülke’ <printed> (cSch); 1 ♀: ‘ CHINA: W-Sichuan 1999 | Ganzi Tibet Aut. Pref., Luding Co. | W Erlangshan-Pass, 2600 m | 7 km SSE Luding, 29°51N | 102°15E, Nadelstreu, Pilze | 29. VI., leg. M. Schülke’ <printed>, ‘Sammlung | M. Schülke | Berlin’ <printed>, ‘ Omalium [handwritten] | sp. [handwritten] | det. M. Schülke 2002’ <printed> (cSch). All paratypes with additional red printed label: ‘ PARATYPE | Omalium | schuelkei sp. nov. | Shavrin A.V. des. 2025’.
Description. Measurements (n=29): HW: 0.55–0.60; HL: 0.36–0.38; OL: 0.15–0.16; TL: 0.05–0.07; AL (holotype): 0.87; PL: 0.46–0.52; PWmax: 0.72–0.80; PWmin: 0.65–0.70; ESL: 0.85–0.97; EW: 0.95–1.05; MTbL (holotype): 0.47; MTrL (holotype): 0.27 (MTrL 1–4: 0.10; MTrL 5: 0.17); AW: 1.02–1.06; AedL: 0.60–0.62; BL: 2.65–3.50 (holotype: 3.25).
Habitus as in Fig. 51. Body reddish-brown, with darker head, pronotum and abdomen (lateral and basal portions of pronotum, elytra, paratergites and intersegmental membranes of abdomen in some paratypes distinctly paler); antennomeres 6–11 or 7–11 brown; mouthparts, antennomeres 1–5 or 1–6 and legs yellow-brown; tarsi yellow. Punctation of head dense or sparse, fine, usually denser in middle, denser and coarser on infraorbital portions; punctation of neck dense, about as that in middle of head; punctation of pronotum moderately dense, usually finer and sparser in medioapical, lateral and mediobasal portions and denser in middle; abdominal tergites with indisinct, fine and sparse punctation. Anterior portion of clypeus with distinct transverse microsculpture, basal portions of clypeus with fine transverse and longitudinal meshes, middle portion sometimes with longitudinal meshes between anteocellar foveae, posterior parts of infraorbital portions usually with distinct longitudinal and diagonal microreticulation; middle part of neck without or with fine transverse or isodiametric meshes; scutellum with fine isodiametric sculpture; abdominal tergites with dense isodiametric microsculpture. Anterior and posterior margins of pronotum with row of short cuticular fringe, invisible in some specimens.
Head 1.5 times as broad as long, with wide and moderately deep anteriomedian depressions, reaching level of anterior third of eyes; posteriolateral margins of clypeus subparallel, stretching posteriad toward level about middle length of eyes. Latero-apical margin between anterior margin of eyes and clypeus with distinct semicircular notch. Dorsal surface sometimes with fine irregular transverse elevations between punctures in middle, infraorbital portions with irregular elongate wrinkles in postocular portions. Anteocellar foveae suboval and deep, slightly convergent latero-apicad toward level of posterior third or middle length of eyes. Temples very short, from two to three times shorter than longitudinal length of eyes. Apical part of neck sometimes distinctly and narrowly depressed, with irregular short elevations between punctures. Ocelli located slightly below level of posterior margins of eyes; distance between ocelli 1.4–1.6 times as long as distance between ocellus and posterior margin of eye. Apical maxillary palpomere about three times as long as penultimate segment. Antenna with slightly transverse antennomeres 6–7 and distinctly transverse 8–10; 5 indistinctly longer and broader than 4, 6 slightly broader than 5, 7 broader than 6, 8 slightly broader than 7, 9–10 slightly longer and distinctly broader than 8, apical antennomere about twice as long as penultimate antennomere.
Pronotum 1.5 times as broad as long, 1.3 times as broad as head, widest in or slightly in front of middle, distinctly more narrowed posteriad than anteriad. Apical angles widely rounded, not protruded anteriad. Anterior margin somewaht straight or rounded, not protruded anteriad, sometimes indistinctly concave in middle. Surface of disc with two long, deep and moderately wide depressions. Each mediolateral portion sometimes with distinct narrow elongate elevations, slightly curved posteriad and reaching middle length of pronotum. Middle portion without elevations between punctures.
Elytra 1.1 times as broad as long, 1.8 times as long as pronotum. Mediolateral surface of each elytron with irregular longitudinal and diagonal elevations.
Metatarsi slightly less than twice shorter than metatibia.
Abdomen slightly broader than elytra.
Male. Posterior margin of abdominal tergite VIII truncate. Posterior margin of abdominal sternite VIII widely sinuate.Aedeagus with wide basal portion, gradually narrowed toward median lobe; median lobe wide and moderately long, from widest basal part gradually narrowed toward small rounded apex; accessory plates short and relatively narrow, each with bilobed apex; parameres relatively narrow, distinctly broadened in preapical parts, reaching about middle of median lobe, each with two moderately long and two short apical setae; internal sac long and moderately narrow, with two small elongate sclerotized structures in basal part (Fig. 56). Lateral aspect of the aedeagus as in Fig. 57; apical portion of median lobe (lateral view) with distinctly truncate ventrolateral margin (Fig. 58).
Female. Posterior margin of abdominal tergite VIII truncate. Posterior margin of abdominal sternite VIII truncate or rounded.Accessory sclerite with wide basal part, gradually anrrowed toward broadened and elongate median part with rounded apex (Fig. 21). Spermatheca not recognized.
Comparative notes. Based on the general shape of the body and the aedeagus, the shape of the elliptic anteocellar foveae, O. schuelkei sp. nov. is similar to the Holarctic O. oxyacanthae. The new species can be distinguished from it by the larger body (the body of O. oxyacanthae varies from 2.2 to 2.6 mm), denser and coarser punctation of the pronotum and the elytra, broader and shorter median lobe, slightly broader parameres, and different shape of the female accessory sclerite.
Distribution. Omalium schuelkei sp. nov. is known from several localities from Gansu and Sichuan, China (Fig. 48).
Etymology. Patronymic; the species is named to honour Michael Schülke (Berlin), one of the collectors of the type specimens.
Bionomics. Specimens were collected at elevations from 2225 to 3230 m a.s.l. and were taken by sifting litter, mosses and mushrooms in mixed (Picea, Populus, Betula) and coniferous forests. One specimen from Xiahe was collected using pitfall traps. The photograph of the type localities in Sichuan as in Fig. 62 (CH 12-21).
description: Published as part of Shavrin, Alexey V., 2025, Review of the genus Omalium Gravenhorst, 1802 (Coleoptera: Staphylinidae: Omaliinae: Omaliini) of China, pp. 501-543 in Zootaxa 5588 (4) on pages 523-526, DOI: 10.11646/zootaxa.5588.4.1, http://zenodo.org/record/14896684