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

description: 3.5.4. Omalium pseudojaponicum sp. nov.
(Figs 65, 72–75)
Type material examined. Holotype ♂ (dissected): CHINA: GANSU: ‘CHINA, Gansu, Yonghai | cca 20 km SW Yuzhong | 2700–2800m, 9.VIII.94 | A. Smetana [C34]’ <printed>, ‘HOLOTYPE | Omalium | pseudojaponicum sp. nov. | Shavrin A.V. des. 2025’ <red, printed> (CNC).
Paratype 1 ♂ (Fig. 65): same data as the holotype, with additional red printed label: ‘HOLOTYPE | Omalium | pseudojaponicum sp. nov. | Shavrin A.V. des. 2025’ (cSh).
Description. Measurements (n=2): HW: 0.60–0.62; HL: 0.42; OL: 0.17; TL: 0.05; AL (holotype): 0.97; PL: 0.52; PWmax: 0.71–0.80; PWmin: 0.65–0.72; ESL: 0.95–1.01; EW: 1.03–1.07; MTbL (holotype): 0.42; MTrL (holotype): 0.26 (MTrL 1–4: 0.09; MTrL 5: 0.17); AW: 1.03–1.05; AedL: 0.72; BL: 3.30 (holotype)–3.35.
Habitus as in Fig. 65. Head, pronotum and abdomen reddish-brown; elytra yellowish-brown, with slightly darkened mediobasal and lateral portions; antennomeres 6–11 brown; mouthparts, antennomeres 1–5 and legs yellow. Punctation of head irregular, moderately large and deep, denser in middle part; neck with moderately large and sparse punctation; punctation of pronotum irregular, sparser in middle and lateral portions, mediobasal portion between longitudinal depressions impunctate (paratype); middle part of elytra with fine and sparse punctation, mediolateral and apical parts with distinctly denser, larger and deeper punctation; abdominal tergites with indistinct, fine and sparse punctation. Anterior portion of clypeus with fine transverse microsculpture, basal portions of clypeus with dense transverse meshes; scutellum without sculpture; abdominal tergites with dense transverse microreticulation.
Head with wide and deep anteriomedian depressions, reaching level of anterior third of eyes. Latero-apical margin between anterior margin of eyes and clypeus with moderately wide and deep semicircular notch. Dorsal surface with irregular transverse and diagonal elevations between pucntures in middle and in posterior parts of infraorbital portions. Anteocellar foveae deep and elongate, slightly convergent latero-apicad toward level of middle length of eyes and indistinctly connected with lateroapical depressions between apical margin of eyes and clypeus. Temples more than three times shorter than longitudinal length of eyes, from posterior margins of eyes strongly narrowed toward neck. Apical part of neck narrowly depressed, with irregular short and longitudinal elevations. Distance between ocelli about twice as long as distance between ocellus and posterior margin of eye. Apical maxillary palpomere about two and a half times as long as penultimate segment. Antenna with sligthtly transverse antennomeres 6–7 and distinctly transverse 8–10; 3 slightly longer and distinctly narrower than 2, 4 1.3 times as long as 3, 5 distinctly longer than 4, 6 distinctly broader than 5, 7 slightly longer and broader than 6, 8 slightly longer and broader than 7, 9–10 slightly longer and broader than 8.
Pronotum 1.3–1.5 times as broad as long, from widest middle gradually narrowed both posteriad and anteriad. Apical angles widely rounded, not protruded anteriad. Anterior margin rounded, not protruded anteriad, slightly concave in middle. Laterobasal portions not concave in front of obtuse hind angles. Lateral portions moderately deeply and widely impressed, distinctly deeper in about middle. Surface of disc with two moderately long and deep longitudinal depressions; surface between depressions slightly and widely elevated; latero-apical parts with narrow elongate elevations, reaching middle. Middle portion without elevations between punctures.
Elytra 1.8–1.9 times as long as pronotum, from basal portion distinctly broadened posteriad; hind margins straight. Dorsal surface of each elytron with irregular elevations between punctures.
Metatarsi less than twice as long as than metatibia.
Male. Posterior margin of abdominal tergite VIII truncate. Posterior margin of andominal sternite VIII sinuate. Aedeagus with wide and relatively short basal portion, gradually narrowed towad median lobe; median lobe narrow, elongate, from widest middle with widely rounded projections slightly narrowed toward small rounded apex; accessory plates elongate and narrow, rounded apically; each paramere significantly broadened in middle and slightly narrowed toward rounded apex, reaching middle of median lobe, with two long apical and one short preapical setae; internal sac narrow and long, without sclerotized structures (Fig. 72). Lateral aspect of the aedeagus as in Fig. 73; apical portion of median lobe (lateral view) hook-shaped, with distinct moderately wide four ventrolateral teeth, largest ventrolateral tooth relatively long (Fig. 74).
Female unknown.
Comparative notes. Based on the coloration of the body, the general shape of the body and the aedeagus, O. pseudojaponicum sp. nov. is similar to O. japonicum Sharp, 1874, known from Japan (Honshu, Kyushu) and South Korea (Watanabe 1990, Kim & Ahn 2014). The new species can be distinguished from it by the longer body, denser and coarser punctation of the head and the pronotum, the longer elytra, longer and narrower median lobe with significantly broader mediolateral projections, narrower parameres and other details of the morphology of the aedeagus.
Distribution. Omalium pseudojaponicum sp. nov. is known only from the type locality in Gansu, China (Fig. 75).
Etymology. The name of the new species is based on the morphological similarity to O. japonicum Sharp, 1874, with the Greek prefix ψευδής (false).
Bionomics. Specimens were collected at elevations from 2700 to 2800 m a.s.l. The detailed bionomical data are unknown.
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 532-533, DOI: 10.11646/zootaxa.5588.4.1, http://zenodo.org/record/14896684