Omalium asturicum Fauvel, 1900

(Figs 2, 9–11)

Homalium asturicum Fauvel, 1900: 221.

Omalium asturicum; Zanetti 2002: 62.

Type material. Lectotype of Omalium asturicum Fauvel, 1900 ♂ (Fig. 2; dissected prior to the present study): SPAIN: ‘ Asturien | Getschman 1379 | Reitter <printed label with thin black margin>, ‘asturiacum | Fvl.’ <handwritten in black>, ‘R.I.Sc.N.B. 17.479 | Omalium [handwritten in black] | Coll. et det. A. Fauvel’ <printed>, ‘Ex-Typus’ <white label with thin black margins, printed in red>, ‘LECTOTYPUS’ <red, printed>, ‘ Omalium | asturicum Fauvel, 1900 | Shavrin A.V. det. 2024’ <printed> (IRSNB).

Paralectotypes: 1 ♂: first three labels as that in the holotype, with additional labels: ‘Paralecto- | typus’ <red, printed>, ‘ Omalium | asturicum | Fauv. | det. Zanetti 2000 [printed]’ <handwritten in black> (IRSNB); 1 ♂ (dissected), 1 ♀ (dissected): ‘ Asturien | Getschman 1379 | Reitter’ <handwritten in black>, ‘Coll. et det. A. Fauvel | Omalium [handwritten in black] | asturicus Fauv. [handwritten in black] | R.I.Sc.N.B. 17.479’ <printed>, ‘Ex-Typus’ <white label with thin black margins, printed in red>, ‘Paralecto- | typus’ <red, printed>, ‘ Omalium | asturicum | Fauv. | det. Zanetti 2000 [printed]’ <handwritten in black> (IRSNB). All paralectotypes with additional printed label: ‘ Omalium | asturicum Fauvel, 1900 | Shavrin A.V. det. 2024’.

Additional material examined. SPAIN: ASTURIAS: 1 ♂: ‘Asturien Getschman 1879 Reitter’ (NMW); 1 ♂: ‘ Asturien’ (NMW); LEÓN: 1 ♀: ‘Caboalles Paganetti’, ‘Ex coll. Bettinger’ (IRSNB); 5 ♂♂, 2 ♀♀: ‘ Caboalles Paganetti’ (NMW); 1 ♀: ‘ Caboalles’ (NMW); 2 ♂♂: ‘ Astorga Paganetti’ (NMW); MADRID: 3 ♂♂: ‘ Umg. Escorial Hi.c., lg. H.Franz’ (NMW); 1 ♂, 1 ♀: Sistema Central Mts., Pinilla del Valle, 40°91' -3°82'. 28.04.2014. A.V. Shavrin leg. (cSh); BADAJOS: 1 ♀: Fuenoaeliente, Sierra Madrona, Fuente del Almiréz, 38°28'N 4°21'W. 790 m a.s.l. J.L. Lencina & C. Andujar leg. (NMW); MÁLAGA: 3 ♀♀: Sierra de las Nieves, Yunquera vic. 36°74'N -4°97'W. 13- 14.05.2014. A.V. Shavrin leg. (cSh); GRANADA: 1 ♂: Sierra Nevada Mts., Veleta. 2300 m a.s.l. 29.09.2008. H. Meybohm leg. (NMW); 6 ♂♂, 4 ♀♀: same Mts., Capileira vill., Rio Nante, 36°99'N - 3°35'W. 1550 m a.s.l. 08- 09.05.2014. A.V. Shavrin leg. (cSh); 2 ♀♀: same Mts., pto. de la Ragua, 37°09'N - 3°02'W. 2000 m a.s.l. 08- 09.05.2014. A.V. Shavrin leg. (cSh).

Redescription. Measurements (n=39): HW: 0.45–0.47; HL: 0.33–0.36; OL: 0.13–0.15; TL: 0.08–0.10; AL (holotype): 1.02; PL: 0.40–0.47; PWmax: 0.62–0.65; PWmin: 0.57–0.60; ESL: 0.72–0.80; EW: 0.85–0.90; MTbL (holotype): 0.45; MTrL (holotype): 0.17 (MTrL 1–4: 0.07; MTrL 5: 0.10); AW: 0.82–0.85; AedL: 0.52; BL: 2.28– 3.07 (lectotype with extended abdomen).

Habitus as in Fig. 2. Body and antennae reddish-brown, with distinctly darker head and slightly paler antennomeres 1–5; mouthparts and legs yellowish-brown; tarsi yellowish. Punctation of head dense, sparser in apical half and denser, coarser and deeper in middle and postocular portions; nuchal constriction with dense punctation about as that in mediobasal portion of head; punctation of pronotum dense, large and deep, but slightly sparser than that in median part of head, sparser in middle and mediobasal third; scutellum without punctures; punctation of elytra dense, about as that on pronotum, but coarser and deeper in middle, and finer and sparser around scutellum and along suture; abdominal tergites without distinct punctures or with fine and very sparse punctation. Forebody without microsculpture except of anterior portion of clypeus with fine transverse microreticulation; abdominal tergites with dense isodiametric sculpture. Anterior portion of head with several moderately long and erect setae; abdominal tergites with sparse, fine and short setation.

Head 1.3 times as broad as long, with broad clypeus and strongly elevated supra-antennal elevations, with wide and deep anteriomedian depressions, reaching middle length of eyes; posteriolateral margins of clypeus parallelsided, stretching posteriad toward level about middle length of eyes. Dorsal surface slightly elevated in middle and slightly more convex on infraorbital portions; middle area with irregular longitudinal elevations between punctures, infraorbital portions with diagonal elevations between punctures. Anteocellar foveae wide and deep, linear, stretching anteriad toward level of posterior third or middle of eyes. Temples moderately long, but shorter than longitudinal length of eyes, widely rounded. Medioapical part of nuchal constriction without depression. Ocelli moderately small, located at level of hind portions of temples; distance between ocelli 1.4–1.6 times as long as distance between ocellus and posterior margin of eye. Apical palpomere more than three times as long as slightly transverse penultimate segment, from widest basal part gradually narrowed toward acute apex. Antenna with distinctly elongate antennomeres 2–8 and slightly elongate 9–10; basal antennomere slightly more than two and a half times as long as wide, 2 about twice narrower and distinctly shorter than basal antennomere, 3 about as long as long and slightly narrower than 2, 4 distinctly shorter than 3, 5 slightly longer than 4, 6 distinctly broader than 5, 7 slightly longer than 6, 8 slightly shorter and broader than 7, 10 slightly broader than 9, apical antennomere about 1.3 times as long as 10, from middle strongly narrowed toward subacute apex.

Pronotum 1.3–1.5 times as broad as long, 1.3 times as broad as head, widest in about middle, distinctly more narrowed posteriad than anteriad; apical angles rounded, not or indistinctly protruded anteriad; hind angles acute, with widely sinuate laterobasal margins; apical margin widely rounded, about as long as somewhat rounded basal margin. Lateral portions deeply and widely impressed, with deep and wide oval depression slightly below middle. Surface of disc with two long and wide longitudinal depressions, significantly broadened and deepened basad; each lateroapical portion around these depressions and median portion distinctly elevated; median surface between punctures in middle with longitudinal elevations, stronger around longitudinal depressions.

Elytra 1.7–1.8 times as long as pronotum; lateral portions moderately widely impressed; hind margins straight or rounded. Surface of each elytron with transverse elevations between punctures around scutellum and longitudinal irregular elevations between punctures in medioapical half.

Abdomen slightly broader than elytra, with two very small oval wing-folding patches in middle of abdominal tergite IV.

Male. Posterior margin of abdominal tergite VIII truncate. Posterior margin of abdominal sternite VIII widely and moderately deeply sinuate. Aedeagus with small and broad basal part, gradually narrowed toward long and narrow median lobe, widely rounded apically; median portion with long sclerotized accessory plates, curved latero-apicad, each rounded apically; parameres short, reaching about middle of median lobe, slightly broadened apically, each with slightly broadened preapical part, rounded apex, three long apical and one preapical setae; internal sac moderately wide and long (Fig. 9 and fig. 42 in Zanetti (2002)). Lateral aspect of the aedeagus as in Fig. 10 and fig. 43 in Zanetti (2002); apical part of median lobe narrow, without ventroapical crenulation and teeth.

Female. Posterior margin of abdominal tergite VIII truncate. Posterior margin of abdominal sternite VIII rounded. Accessory sclerite with wide basal part. Strongly narrowed toward short and narrow apical part (Fig. 11). Spermatheca not recognized.

Comparative notes. Based on the general shape of the body, the aedeagus and the female accessory sclerite, coloration of the body, punctation of head and pronotum, and shapes of anteocellar foveae and temples, O. asturicum is more similar to O. italicum Bernhauer, 1902 (see below). It can be distinguished from the latter species by the broader and slightly shorter elytra, and narrower and longer median lobe with broader apical part.

Distribution. Omalium asturicum is distributed in Spain (Gamarra & Outerelo 2008; Schülke & Smetana 2015).

Bionomics. Omalium asturicum can be collected in leaf litter and mosses near streams and rivers in mixed forests.

Remarks. Homalium asturicum was originally described based on four syntypes from “ Asturies ”. I studied all four syntypes from IRSNB (see above). Zanetti (2002) attributed it to the Caesum group, designated the lectotype and provided the figure of the aedeagus. It was recorded several times from north-western and central Spain (Asturia, León and Madrid provinces), which became the basis for distributional map provided by Gamarra & Outerelo (2008). It is here recorded from Badajos, Málaga and Granada provinces of Spain for the first time.