Bryaxis duboki, Kolimár & Hlaváč & Baňař, 2024

Kolimár, Robert, Hlaváč, Peter & Baňař, Petr, 2024, Two new species of Bryaxis Kugelann, 1794 (Coleoptera, Staphylinidae, Pselaphinae) from Montenegro, Zootaxa 5446 (2), pp. 274-280 : 275-277

Bryaxis duboki sp. nov.

Figs 1–5

Material examined. Holotype, ♂: MONTENEGRO, with one label “Montenegro Mrtvo Duboko / small gorge, sifting 220 m / 42°42'33,10''N, 19°22'9,59''E / lgt Kolimár 1.11.2021 ” [white, printed] ( MMBC) . Paratypes: 5♂♂, 3♀♀: same locality as for the holotype ( PCPH, PCRK) . 8♂♂, 7♀♀: with one label “MONTENEGRO [MNE011] / Međurijećije env., 3.v.2023 / 42°42’33’’N, 19°22’09’’E / 200 m, Fagus , sifting near stream / P.Hlaváč, P. Baňař & R.Kolimár lgt.” [white, printed] ( PCPH, PCRK) . 2♂♂, 1♀: with one label “MONTENEGRO [MNE012] / Crkvine pass env., 3.5.2023 / 42°47'40''N, 19°25'59''E 1050m / Sifting Fagus forest w. old trees / P.Hlaváč, P. Baňař & R.Kolimár lgt.” [white, printed] ( PCRK) . 1♂: with one label “MONTENEGRO [MNE021] Prokletije / Dolina Grebaje, 6.5.2023 / 42°30'29''N, 19°46'48''E 1300m /sifting, snow field on gravel slope / P.Hlaváč, P. Baňař & R.Kolimár lgt.” [white, printed] ( PCRK) . 1♂, 3♀♀: with one label “MONTENEGRO [MNE038] Prokletije / Dolina Grebaje, 6.6.2023 / 42°30'53"N, 19°46'49"E 1200m /, sifting, under stones, Fagus frs./ Kolimár , Šíma, Švarc lgt.” [white, printed] ( PCRK) . 1♂, 2♀♀: with two labels “MONTENEGRO 1170m/ 42°29'57"N 19°49'01"E / Prokletije NP / Rapojane valley ”, “under stone in stony rubble Fagus forest / A. Šíma leg. 4.VI.2023 ” [white, printed] ( PCAS) . 2♂♂: with two labels “MONTENEGRO 1200m / 42°30'53"N 19°46'49"E / Prokletije NP / Grebaje valley ” [white, printed], “sifting & under the stones in stony rubble Fagus forest / A. Šíma leg. 6.VI.2023 ” [white, printed] ( PCAS) .

Diagnosis. Body length 1.56–1.59 mm, reddish-brown; antennae, maxillary palpi and legs slightly lighter; antenna moderately long, scape subcylindrical, slightly narrowing towards the end with small flat, rounded tubercle in basal third, more than twice as long as pedicel, pedicel elongate, about 1.2 times as long as wide, antennomere 3 elongate, 4–7 moniliform, 8–10 transverse; palpomeres 2–3 unevenly granulated; legs slender, protibia in distal third with minuscule tubercle on inner edge, metatibia prolonged by minuscule distal dent on inner edge.

Description. Body ( Figs 1–2 ) shiny, reddish brown, pubescence long and recumbent, legs, antennae and maxillary palpi slightly lighter, body length 1.56–1.59 mm, maximal width of elytra 0.66–0.67 mm.

Head subtriangular, about 1.05 times as wide as long, smooth, rostrum pointed, eyes small, composed of 15– 20 facets; frons between antennal tubercules with deep excavation, reaching almost half of head, rostrum with triangular projection; vertex flat, median vertexal carina well-defined, reaching posterior margin; vertexal foveae small; temples slightly longer than diameter of eyes, rounded.

Maxillary palpi standart developed, palpomeres 2–3 unevenly granulated, palpomere 4 elongate, about 0.30 mm long, evenly and densely pubescent, setae very short.

Antenna long (about 0.70 mm), scape of male about 1.75 times as long as wide, subcylindrical, slightly narrowing distally, with small flat rounded tubercle in basal third ( Fig. 5 ), more than twice as long as pedicel, scape of female about 2.5 times longer than wide ( Fig. 2 ), without tubercles. Pedicel elongate, about 1.2 times as long as wide, antennomere 3 elongate, 4–7 moniliform, 8–10 transverse, antennomere 10 about 1.4 times as long as 9, terminal antennomere 2.5 times as long as 10, as long as scape, pointed at apex.

Pronotum smooth and shiny, coarsely punctate between posterior pronotal margin and transverse antebasal sulcus, about 1.1 times as wide as long, widest in anterior third, 1.2 times as long as head, disc weakly convex, lateral antebasal foveae well-defined, connected by well-developed antebasal sulcus.

Elytra wider than long, about 0.62 mm long and 0.67 mm wide, glossy, disc slightly convex, with even shallow minuscule punctures, each elytron with two basal foveae, with humeral projection; with sutural stria and lacking discal stria.

Abdomen about 2.5 times shorter than elytra, covered with sparse semi-erected long setae.

Legs slender and relatively long, protibia on inner edge with small tubercle located in distal third, on outer edge prolonged by minuscule distal dent, metatibia prolonged by minuscule distal dent on inner edge.

Aedeagus ( Figs 3–4 ) symmetrical, about 0.37 mm long, robust, about 1.53 times as long as wide, basal bulb sub-spherical; parameres broad with rounded sides; distal lobe bent inwards and pointed, each with three pre-distal setae; endophallus with massive structure composed from pair of wide, lateral and pair of slender, median sclerites, all with numerous spines on distal portion.

Sexual dimorphism. Females with scape simple, cylindrical, 2.5 times longer than wide, protibiae and metatibae simple, femora and tibiae slightly more slender.

Remarks. Bryaxis duboki is similar to Bryaxis verrucipalpis ( Apfelbeck, 1907) sharing with this species the similar shape of the scape and pedicel as well as the granulation of palpomeres 2 and 3. It can be readily separated from latter by the different shape of the aedeagus and the presence of the tubercle located in distal third of protibiae.

Natural history. All specimens were collected by sifting of leaf-litter in deciduous Fagus forests. No other details concerning the biology of this species are known.

Etymology. The name refers to the name of the type locality Mrtvo Duboko.

Distribution. Montenegro.

Figures

FIGURES 1–5. Bryaxis duboki sp. nov. 1, male holotype, dorsal habitus; 2, female paratype, dorsal habitus; 3, 4, aedeagus in ventral view (colour photograph and drawing respectively); 5, male holotype, apex of head with scape and pedicel, arrows indicate minute tubercles on dorsal face of scape. Scale bar in mm.