Quedius (Raphirus) humosus Solodovnikov

Yu, A. & Solodovnikov, 2005, New and little known species of Quedius from West Palaearctic (Coleoptera: Staphylinidae: Staphylininae), Zootaxa 902, pp. 1-13 : 10-12

Quedius (Raphirus) humosus Solodovnikov , sp. nov.

Type material. GEORGIA: holotype: ɗ, “W Caucasus, Abkhazia, Bzybsky range, near Otkhara, 400 m, pitfall trap, 15.V–25.VII.1998, leg. A. Koval” ( FMNH); paratypes: 1 Ψ, “Abkhazia, Gagry [label in Cyrillic]/ Quedius obliqueseriatus J. Boh ảč det. 1983” ( ZIN); 1 Ψ, “Cauc.[Caucasus] Occ. [Occidentalis] Gagry, [leg.] A. Zolotarew” ( SNM).

Description. Measurements (min–max; n=3): HL: 1.15–1.30; HW: 1.45–1.60; PL: 1.70–1.80; PW: 1.85–2.00; EL: 1.55–1.62; EW: 1.80–2.00. Body length 8.6–9.7 mm.

Head and abdomen dark brown; disk of pronotum from reddish­brown to brown; elytra reddish­brown; mouthparts, antennae, legs, posterior margins of abdominal tergites yellowish­brown; body glossy, abdomen slightly iridescent. Habitus as in Fig. 3 .

Head slightly transverse, tempora half as long as longitudinal diameter of eye; upper surface with microsculpture of transverse waves. Infraorbital ridges well developed through entire length of head, from about its base to base of mandibles. Labrum short, bilobed. Mandibles without well developed dorso­lateral groove. Apical segments of maxillary and labial palps fusiform. Disc of head with pairs of anterior and posterior frontal punctures, and pair of vertical punctures: posterior frontal puncture closer to posterior margin of head than to anterior frontal puncture; temporal puncture closer to posterior margin of eye than to posterior margin of head; vertical puncture closer to posterior margin of head than to posterior margin of eye.

Antennae moderately long; antennomeres: 2nd shorter than 3rd, 4th–10th of rather equal length, 6th–10th obviously wider than 4th and 5th; 4th–11th densely pubescent.

Pronotum wider than long, widest at middle, narrowed anteriad; hind angles broadly rounded but distinct; dorsal rows each with three punctures; sublateral rows each consisting of two punctures; waves of microsculpture oblique, similar to those on head; microsculpture on anterior angles of pronotum transversally reticulate. Prosternum with longitudinal keel and pair of long macrosetae. Scutellum impunctate, with transverse microsculpture as on pronotum. Elytra short, parallel­sided, wider than long, shorter than pronotum and narrower than maximum width of pronotum; punctation very dense and shallow, interspaces smaller than diameter of punctures, glossy, with vague minute irregularities; pubescence gray. Wings reduced.

Abdomen with tergite VII (5th visible) without distinct apical seam of palisade fringe; punctation moderately dense, gradually becoming sparser towards apex of abdomen; pubescence as on elytra; interspaces with very superficial transverse irregularities.

Male. Protarsi with tarsomeres I–IV dilated, ventrally with whitish adhesive setae. Sternite VIII with triangle­shaped medio­apical emargination. Tergite X cordate with obtuse, weakly sclerotized apical margin and apical setae slightly longer than rare general setation. Sternite IX long, gradually narrowed apicad, with wide basal portion and vaguely bilobed apical margin, with long apical setae and shorter general setation. Aedeagus ( Figs. 11–13 ): median lobe with moderately large basal part and lanceolate (in dorsal or ventral view) apical portion; median lobe with tooth dorsally (at side adjacent to paramere), situated relatively far from its apex. Paramere by far not reaching apex of median lobe, gradually narrowing apicad, with obtusely pointed apex, with two pairs of setae apically and two pairs of longer setae laterally below apex, with about 30 sensory peg setae arranged in one loose, irregular group. Internal sac (as seen through the walls of median lobe) with group of stronger sclerotized microstructures at its apex.

Female. Anterior tarsi with tarsomeres I–IV dilated (but less so than in males), with whitish adhesive setae ventrally. Sternite VIII concave. Tergite X cordate with broadly rounded apical margin and group of apical macrosetae.

Distribution. Known only from the area of Gagrsky and Bzybsky ranges in Abkhazia ( Georgia).

Bionomics. Bionomics is not recorded. Quedius humosus appears to be a leaf litter inhabitant since one of the three specimens was taken from a pitfall trap.

Comparison. The new species is closely related to Q. obliqueseriatus but differs from the latter in the presence of only one pair of vertical punctures (situated medio­basally from the posterior frontal punctures), the shape of the aedeagus, and the rounded (nonemarginate as in Q. obliqueseriatus ) apex of the female abdominal tergite X. Unlike Q. obliqueseriatus , in which two pairs of vertical punctures together with the posterior frontal puncture form very characteristic oblique rows of punctures behind the eyes, Q. humosus has only two punctures behind the eye: the posterior frontal, and one vertical. The aedeagus of Q. humosus has the dorsal tooth situated farther from the apex of the median lobe and a relatively shorter paramere by far not reaching the apex of the median lobe.

Etymology. The species name is derived from the Latin adjective “ humosus ” (living in humus) and refers to the habitat of this and many other species of Quedius confined to the humus­rich layer of forest leaf litter.

Figures

FIGURES 1 – 4. Quedius species, habitus. 1 Q. nonseriatus sp. nov., holotype; 2 Q. henrii sp. nov., holotype; 3 Q. humosus sp. nov., holotype; 4 Q. walteri Korge.

FIGURES 5 – 17. Quedius species, aedeagi. 5 – 7 Q. nonseriatus sp. nov.; 8 – 10 Q. henrii sp. nov.; 11 – 13 Q. humosus sp. nov.; 14 – 17 Q. walteri Korge; 5, 8, 11, 14 aedeagus laterally; 6, 9, 12, 15 aedeagus dorsally (parameral side); 7, 10, 13, 16 apical portion of paramere ventrally (side adjacent to median lobe); 17 apical portion of paramere latero­ventrally.