Omaliopsis russata ( Fairmaire & Germain, 1861 )

Shavrin, Alexey V., 2022, On some species of Omaliini McLeay, 1825 of Chile (Coleoptera: Staphylinidae: Omaliinae), Zootaxa 5141 (2), pp. 174-182 : 175-176

Omaliopsis russata ( Fairmaire & Germain, 1861)

( Figs. 1–2 , 7–12 )

Omalium russatum Fairmaire & Germain, 1861: 453

Omaliopsis russata: Coiffait & Saiz 1968: 451 ; Saiz 1969: 4

Type material examined. Syntypes, 2 ♂♂ (one male as in Fig. 1 ), 1 ♀ (dissected): ‘ Chili | Chiloë’ <handwritten>, ‘Coll. et det. A. Fauvel | Omalium [handwritten] | russatum Fairm. [handwritten] | R.I.Sc.N.B. 17.479’ <printed>, ‘ex-Typis’ <label printed in red, with black frame>, ‘ Omaliopsis | russata Fairmaire & Germaine, 1861 | Shavrin A. V. det. 2022’ <printed> ( IRSN).

Additional material examinded. CHILE: 1 ♀: Palguin , - 39.30°S - 71.80°W. Car net. 05.12.2013. T . Struyve leg. (cSt); 4 ♂♂, 1 ♀: Corral , - 39.95°S - 73.20°W. Car net. T . Struyve leg. (cSt); 4 ♂♂, 9 ♀♀: Alerce Costero , - 40.20°S - 73.43°W. Car net, road to Parque Naturel. T . Struyve leg. (cSt, cSh); 1 ♂: Aguas Calientes , - 40.75°S - 72.30°W. Car net. 13.12.2013. T . Struyve leg. (cSt); 1 ♀: Lenca , - 41.58°S - 72.57°W. Litter layer. 18.12.2013. T . Struyve leg. (cSh); 1 ♂, 1 ♀: Malleco Province , 14 km E Malalcahuello. 13- 31.12.1982. 1579 m a.s.l., Nothofagus pumilio - Araucaria forest, fine debris under bark of Nothofagus logs, trap site 649. A. Newton & M. Thayer leg. ( MHNG) ; 1 ♂: ‘ Punta Arenas (Patagonie) e corces [19]12’ ( IRSNB) .

Redescriptio n. Measurements (n=26): HW: 0.47–0.52; HL: 0.30–0.37; AL (averaged): 0.84; OL: 0.12–0.15; PL: 0.35–0.39; PW: 0.59–0.62; ESL: 0.82–0.86; EW: 0.75–0.85; AW: 0.70–0.75; MTbL (averaged): 0.28; MTrL (averaged): 0.19 (MTrL 1–4: 0.07; MTrL 5: 0.12); AedL: 0.34–0.40; TL: 1.95–3.20.

Habitus as in Figs. 1–2 . Body yellow-brown to reddish-brown; head, median part of pronotum in some specimens, mediobasal, lateral and apical portions of elytra brown to black (some specimens entirely brown, with darkened mediobasal portion of pronotum); antennomeres 6–11 brown; mouthparts, antennomeres 1–5, infraorbital ridges of head, lateral and mediobasal portions of pronotum, latero-apical, median and medioapical portions of elytra, paratergites and apical portions of abdominal terites in some specimens yellow to yellow-brown. Punctation of head fine and sparse, larger and denser on infraorbital ridges or very indistinct in some specimens; neck without or with very fine and sparse punctation; punctation of pronotum very dense, somewhat larger than that on head, distinctly larger on lateral and finer and sparser on mediobasal portion; scutellum without punctation; punctation of elytra dense, larger than that on pronotum, denser on parascutellar and apical portions, finer in middle portion (some specimens) and along suture; abdominal tergites without or with fine and moderately dense punctation. Forebody glossy; microsculpture of head dense, distinctly denser on infraorbital ridges: anterior portion with transverse meshes, middle portion with cellular and diagonal sculpture, and infraorbital ridges with diagonal microreticulation; neck with dense, transverse microsculpture (some specimens with indistinct meshes in middle); pronotum with dense transverse and diagonal microsculpture, finer in mediobasal portion in some specimens; scutellum with fine or very dense transverse microsculpture; elytra without microreticultation; abdominal tergites with very dense and coarse sculpture.Anterior portion of head with moderately long, erect setation; lateral portions of pronotum and elytra with several semierect setae; abdomen with moderately dense setation, longer on apical portions of abdominal tergites and paratergites; posterior margin of pronotum with a row of short cuticular fringe (invisible in some specimens).

Head 1.4–1.5 times as broad as long, with slightly elevated frons, vertex and infraorbital ridges, with very short temples and deep, anteocellar foveae (grooves in front of ocelli) diagonally stretching anteriad to level of posterior third or middle of eyes. Eyes moderately large, convex; postocular ridges distinct, obtuse, distance between posterior margin of eye and postocular ridge about as diameters of two-three nearest ommatidia. Ocelli moderately large and convex, distance between ocelli about as long as distance between ocellus and posterior margin of eye or slightly shorter. Maxillary palpomeres moderately narrow, apical palpomere usually more than four times as long as small and slighly transverse penultimate segment. Antennae short, reaching posterior margin of pronotum or basal margin of elytra when reclined; apical six antennomeres with strong and long pubescence; antennomeres 6–10 distinctly transverse; basal antennomere moderately wide, more than twice as long as broad, antennomere 2 suboval, distinctly longer than broad, 3 distinctly narrower and about as long as 2, 4 small, suboval, about as long as broad, 5 oval, slighty longer than 4 and longer than broad, 6 significantly broader than 5, about twice as broad as long, 7 slightly broader than 6, 8–10 slightly broader than 7, apical antennomere about twice as long as 10, from apical third gradually or strongly narrowed toward subacute apex.

Pronotum transverse, convex in median portion, 1.5–1.6 times as broad as long, 1.1–1.2 times as broad as head, widest in anterior third, distinctly more narrowed posteriad than anteriad; anterior angles widely rounded, not protruded anteriad; posterior angles obtuse; lateral edge with distinct, more or less regular small crenulation; surface of disc with two distinct and very wide longitudinal impressions, beginning from medioapical and significantly broadened in mediobasal portions; lateral portions deeply impressed, with moderately deep oval impressions in about middle; each latero-apical portions with distinct, narrow, moderately long and semicircularly curved elevation, beginning from apical margin and stretching toward about middle length of pronotum.

Elytra slightly longer than broad, more than twice as long as pronotum, somewhat parallel-sided or slightly broadened posteriad; lateral margins marginated; latero-apical edges with indistinct smooth crenulation; hind margins of elytra straight. Hind wings fully developed.

Metatarsus 1.4 times as long as metatibia; apical metarsomere markedly longer than four preceding tarsomeres.

Abdomen convex, narrower than elytra, with two moderately small, oval wing-folding patches (tomentose spots) in middle of abdominal tergite IV and narrow palisade fringe on apical margin of abdominal tergite VII.

Male. Protarsomeres 1–4 wide. Apical margin of abdominal tergite VIII somewhat rounded ( Fig. 9 ). Medioapical portions of abdominal sternite VIII with paired subtriangular tooth-like processes; apical margin deeply and widely concave ( Fig. 10 ). Aedeagus suboval, with widely rounded apex; parameres moderately narrow, short, significantly not reaching apex of median lobe, with three short apical setae and four short setae on inner edges of each paramere; internal sac wide, moderately short, with two lateral and two median long fields of sclerotized thorns ( Fig. 7 ). Lateral aspect of aedeagus as in Fig. 8 .

Female. Protarsomeres 1–4 moderately narrow. Apical margin of abdominal tergite VIII straight ( Fig. 11 ). Apical margin of abdominal sternite VIII widely rounded ( Fig. 12 ).

Comparative notes. Omaliopsis russata can be distinguished from all congeners by the presence of narrow latero-basal elevations of the pronotum, the shape of wide median lobe of the aedeagus and short parameres.

Distribution. Omaliopsis russata is known from several localities in the southern part of Chile.

Bionomics. Some specimens were collected using car net or were sifted from litter, or were found under the bark of Nothofagus pumilio .

Figures

FIGURES 1–6. Habitus of species of Omaliini: 1—Omaliopsis russata (male, syntype), 2—O. russata (Chile, Aguas Calientes), 3—O. struyvei (holotype), 4—Stenomalium picipennis (syntype), 5—S. sp. (female; Chile, Corral), 6—Xenanthobium andicola (Chile, Corral). Scale bar: 1.0 mm.

FIGURES 7–12. Omaliopsis russata (7–10: Chile, Aguas Calienetes; 11–12: Chile, Corral): 7—aedeagus (parameral view), 8—aedeagus (lateral view), 9—male abdominal tergite VIII (dorsal view), 10—male abdominal sternite VIII (ventral view), 11—female abdominal tergite VIII (dorsal view), 12—female abdominal sternite VIII (ventral view). Scale bar: 0.10 mm.