Quedius (Distichalius) gissaricus, Salnitska & Solodovnikov, 2022

Salnitska, Maria & Solodovnikov, Alexey, 2022, New species and records of Quedius rove beetles (Coleoptera, Staphylinidae, Staphylininae) from Middle Asia, European Journal of Taxonomy 823, pp. 141-157 : 148-150

Quedius (Distichalius) gissaricus sp. nov.

urn:lsid:zoobank.org:act:2C73B7D0-9EEB-4C5D-903C-52786634ADBE

Figs 1–2

Diagnosis

Among other members of Distichalius Casey, 1915, the new species can be distinguished by the following combination of characters: body relatively small, head with interocular punctures (red arrows in Fig. 1A ), elytra with rough and very sparse punctation arranged in irregular rows; median lobe of symmetrical aedeagus simple, without apical lobes, with distinct apex; paramere with several sensory peg setae apically arranged in short rows along parameral margins with apical setae.

Etymology

The species name ‘ gissaricus ’ (latinized adjective) is derived from the mountain range where this specimen was collected.

Type material

Holotype TAJIKISTAN • ♂ (left tarsus and tergite VIII damaged, sternite IX, lateral tergal sclerites and the tergite of segment X lost); “TADJIKISTAN, N slope of Gissar Mnt range, 2500 m a.s.l., 19.7.1990, Kuzminih leg./ Quedius (Quedionuchus) sp. Klimenko det./ Tadjikistan N slope of Gissar Mnt range 2500 m a.s.l. 19.7.1990 Kuzminih [in Russian]/ A.A. Klimenko collection”; ZIN.

Description

MEASUREMENTS AND RATIOS. HL: 0.82; HW: 0.84; PL: 1.02; PW: 1.07; EL: 1.25; EW: 1.23; FB: 3.09; TL: 6.27; HL/HW: 0.97; PL/PW: 0.96; EL/EW: 0.92; PL/EL: 0.60; PW/EW: 0.87.

COLOURATION. Body black ( Fig. 1A ) with reddish appendages; head and pronotum completely black; elytra and abdomen black with paler margins.

HEAD. About as wide as long (HL/HW: 0.97), surface with microsculpture of transverse waves on disk and between eyes. Eyes large, moderately convex, temples 1.5 times as long as longitudinal diameter of eye. Head chaetotaxy as in Fig. 1A . Anterior frontal puncture touching anteriomedian margin of eye, with barely visible additional interocular punctures between anterior frontal punctures (red arrows in Fig. 1A ); posterior frontal puncture situated closer to posterior margin of eye than to nuchal ridge, pair of smaller basal punctures situated close to nuchal ridge; each temple with two temporal punctures, posterior one situated halfway between posterior margin of eye and nuchal ridge; temples additionally with some fine setiferous punctures bearing short yellowish setae. Antennae moderately long, first segment shorter than second and third segments together; third distinctly longer than second, fourth and fifth slightly longer than wide, sixth to tenth wider than long, gradually increasing in width towards apex of antenna, last fusiform segment distinctly longer than penultimate segment.

PRONOTUM. Barely wider than long (PL/PW: 0.96), widest at about middle; with nearly parallel sides at middle, posterior lateral portions barely explanate. Disk of pronotum with two dorsal rows of punctures, each with three punctures, third (basalmost) puncture situated behind the level of large lateral puncture; sublateral area with three punctures (one additional between dorsal and sublateral row), posterior two of which situated on one line slightly between level of basalmost puncture of dorsal row; basal margin with row of three variably sized setae on each side; microsculpture of transverse waves, sparser than on head.

SCUTELLUM. Impunctate, with faint transverse microsculpture.

ELYTRA. Vaguely widening posteriad, slightly wider than long (EL/EW: 0.92), longer and wider than pronotum (PL/EL: 0.60, PW/EW: 0.87); punctation rough and very sparse, consisting of single widely spaced punctures arranged in irregular rows; interspaces without microsculpture; pubescence yellowish to brownish, short, sparse.

WINGS. Fully developed.

ABDOMEN. Punctated more densely than elytra, punctation becoming sparser toward apex; tergite II with very fine and distinct punctures; posterior margin of tergite VII with whitish palisade fringe.

Male

First four protarsomeres markedly dilated, each densely covered with modified pale setae ventrally; second segment as wide as, or slightly narrower than apex of tibia. Sternite VIII with two long setae on each side; apical margin with weak triangular medio-apical emargination ( Fig. 1E ).

Aedeagus ( Fig. 1B–D ) rather small (0.9 mm), median lobe (in parameral or anteparameral view) symmetrical, parallel-sided along most of its length, with evenly narrowed apical portion; (in lateral view) with fine short longitudinal subapical carina ( Fig. 1D ), with obtusely pointed and gradually narrowed apex and minute subapical tooth. Paramere (in parameral view) nearly reaching apex of median lobe, distinctly narrower than median lobe, symmetrical, vaguely narrowed to obtusely pointed apex ( Fig. 1B ); (underside) apically with two longitudinal rows of five peg setae at each lateral margin ( Fig. 1C ). Internal sac without large sclerotized structures.

Female

Unknown.

Remarks

In addition to the holotype of Q. gissaricus sp. nov., there was another specimen of Distichalius collected at the same locality, but some days earlier (for details see Q. (D.) sp. aff. gissaricus below). That specimen differs from the holotype of Q. gissaricus sp. nov. by the distinctly paler pronotum, elytra and appendages, lacking interocular punctures between frontal punctures, less regular punctation of elytra, tergite II with fine and shallow punctation, and median lobe of the aedeagus with smaller subapical tooth located considerably further away from the apex. Given the co-occurrence of the two specimens and their subtle difference from each other, they may be considered either as variants of one morphologically variable species, or one of them could be an aberrant specimen, or they may represent closely related sympatric species. Since a firm conclusion is impossible until more material is examined, we tentatively identify the second specimen as a separate species and list it below.

Ecology

Quedius gissaricus sp. nov. is hitherto known only from the Gissar Mountain Range in Tajikistan where it was collected at an elevation of 2500 m ( Fig. 2 ).

Comparison

Without a complete revision of species currently in Distichalius it is impossible to place Q. gissaricus sp. nov. in a species group. It differs from other smaller Western Palaearctic Distichalius (e.g., Q. punctatellus (Heer, 1839) and allied ones with which it shares the sparse punctuation of the elytra arranged in rows) by the presence of interocular setae on the head and by a smaller number of sensory peg setae on the paramere, which do not extend behind the apical setae towards the parameral base. As can be judged from Smetana (2017), it is distinct from any of the Chinese species at least as follows: it differs from the Q. ladas , Q. bipictus and Q. daedalus groups by a sparse irregular punctation of the elytra which form rows; from the Q. annectens group by the aedeagus without apical lobes; from the Q. laetipictus group at least by a uniform dark body colouration; from the Q. regularis group by a pointed, not widely arcuate apex of the aedeagal median lobe. Our new species differs from all Far Eastern and Japanese species by a smaller body size and the shape of the aedeagus.

Figures

Fig. 1. Quedius gissaricus sp. nov., holotype (ZIN). A. Habitus (interocular punctures indicated by red arrows). B–D. Aedeagus.B. From parameral side. C. Apical portion of paramere (underside). D. Median lobe (laterally). E. Sternite VIII. Scale bars: A =1 mm; B–E = 0.5 mm.

Fig. 2. Distribution map showing the type localities of Quedius gissaricus sp. nov. (red circle) and Q. viator sp. nov. (violet circle).