Omalium kociani ZANETTI, 2019

Assing, Volker & Schülke, Michael, 2019, The Staphylinidae of Armenia and Nagorno-Karabakh (Coleoptera), Beiträge Zur Entomologie = Contributions to Entomology 69 (1), pp. 91-173 : 151-152

Omalium kociani ZANETTI spec. nov.

urn:lsid:zoobank.org:act:5F24413E-6AB4-4D1C-B567-AB93C38380C9

( Figs 3 , 7–10 )

Type material: Holotype: “ ARMENIA, above Jermuk sifting of plant leavings near snow residues, 2400 m 39,839053N 45,693496E 21.V.2015 M. Kocian lgt. / Omalium kociani n. sp. det. A. Zanetti 2016 / Holotypus ” ( MCSNV) . Paratypes: 5, 3: same data as holotype (cKoc, cZan, cAss).

Etymology: This species is dedicated to the collector,

Matúš Kocian (Praha), specialist of Tachyporinae .

Description: Measurements (n = 9): body length (with extended abdomen) 2.4–3.1 mm; length of forebody from anterior margin of clypeus to posterior margin of elytra 1.53–1.88 mm; head width 0.46–0.51 mm; head length from clypeus to neck 0.35–0.42 mm; width of pronotum 0.61–0.70 mm; length of pronotum 0.42– 0.49 mm; length of elytra from humeral angles to apex 0.70–0.83 mm; length of elytral suture 0.61–0.72 mm; width of elytra 0.75–0.90 mm. Habitus as in Fig. 3 . Coloration: head usually blackish, sometimes brown; pronotum reddish, sometimes with more or less extensive brownish discal area: elytra yellowish red; abdomen brownish with yellowish-brown paratergites; antennae, legs and mouth parts entirely yellowish.

Head moderately transverse, 1.2–1.3 times as broad as long; temporal angles rounded but marked; two ridges extending from above insertion of antennae to compound eyes; surface without microsculpture, with dense and regular punctation forming some irregular striae between eyes and ante-ocellar pits, punctation anteriorly extending to the anterior margin of clypeus; sub-antennal impression rather wide, tentorial pits in front of ocelli long and linear, posteriorly extending to the rather small ocelli, the latter separated by a distance equal to that between ocellus and eye; space between tentorial pits and eyes elevated; neck clearly separated from the rest of the head, with dense punctation similar to that of head. Eyes small, slightly shorter than temples, without infra-orbital carina. Antenna rather thin and elongate, antennomere I elongate, twice as long as wide, II elongate ovoid, III–VIII longer than wide, gradually incrassate, IX–X subquadrate, XI longer than wide.

Pronotum transverse, on average 1.4 times as broad as long and 1.4 times as broad as head, widest in anterior half; anterior margin wider than posterior margin, anterior and posterior angles marked and slightly obtuse; lateral margins with trace of crenulation, weakly sinuate posteriorly; surface of pronotum irregular with three longitudinal elevations and two pits near lateral margin; punctation dense, similar to that of head, ground surface smooth without microsculpture.

Elytra small, 1.5 times as long (measured from humeral angles) and 1.3 times as broad as pronotum; punctation irregular and dense, coarser than on pronotum, interstices without microsculpture. Legs simple, with some spines in the apical portions of the meso- and metatibiae.

Abdomen with isodiametric microsculpture, decumbent pubescence and small wing-folding patches.

: aedeagus as in Figs 7–8 , median lobe with narrow base, strongly enlarged subapically; apex weakly curved dorsad in lateral view and without ventral elevations.

: accessory sclerites as in Fig. 9 ; spermatheca as in Fig. 10 .

Comparative notes: The new species belongs to the Omalium caesum group as defined by ZANETTI (1987): ventral process of the aedeagus proximally much narrower than the basal bulb, parameres distinctly dilated and of intricate structure distally, with very long apical setae, tentorial impressions line-shaped. According to ZANETTI (2002), the following representatives of the O. caesum group are distributed in Turkey, Cyprus and the Caucasus region: O. caesum GRAVENHORST, 1806 , O. littorale KRAATZ, 1857 , O. wunderlei ZANETTI, 2002 , and O. rugatum MULSANT & REY, 1880 ). They are all clearly distinguished from O. kociani by long elytra, rather uniform and dark colour, and by the shape of the median lobe of the aedeagus (ventral process not narrowed at the base). Omalium turcicum SMETANA, 1867 is very similar in coloration and in general shape, but differs by wider elytra, smaller eyes, more rounded temples and confluent punctation of the head, and an impunctate clypeus. However, the only reliable distinguishing character is the shape of the aedeagus: in O. turcicum , the ventral process is gradually narrowed from the base to the obtuse apex ( ZANETTI 2002: figure 58), whereas in O. kociani the ventral process is narrow at the base and enlarged in the middle, and the apex is more acute ( Fig. 8 ). In populations of O. caesum with short elytra from the Alps, the ventral process of the aedeagus has a broad base ( ZANETTI 2002: figure 55). Omalium cribriceps FAUVEL, 1900 , which is distributed in Iran, Iraq, Syria, and Turkey ( SCHÜLKE & SMETANA 2015), is very similar to O. kociani in coloration, habitus, and the punctation of the head, but has an aedeagus of completely different shape ( ZANETTI 2002: figure 48) with wide median lobe and simple, linear parameres.

Distribution and natural history: This species is known only from the type locality in Armenia. The typical series was collected in an alpine meadow by sifting humus and rotting herbs near a small residual snow field.

Figures

Figs 1–6: Type locality ofBellatheta khustupica in the peak region of Mount Khustup (1); microhabitat whereB. khustupica was

Figs 7–23:Omalium kociani (7–10), Proteinus baculatus (11–14), Bryaxis armeniacus (15, 17), B. meghruicus (16, 18), Aleochara fugax (19–21), and Atheta meghruica (22–23): (median lobe of) aedeagus in lateral and in ventral view (7–8, 13–16); female accessory sclerites (9); spermatheca (10, 21); habitus (11, 19, 22); thorax in ventral view (12); male antennomeres I–III (17–18); posterior margin of female sternite VIII (20); forebody (23). Scale bars: 11, 19, 22: 1.0 mm; 12, 23: 0.5 mm; 7–10, 13–16, 20–21: 0.1 mm; 17–18: without scale.