Bergrothia barbakadzei Maghradze, Faille, Barjadze & Hlaváč, 2019

Maghradze, Eteri, Faille, Arnaud, Barjadze, Shalva & Hlaváč, Peter, 2019, A new cavernicolous species of the genus Bergrothia Reitter, 1884 (Coleoptera, Staphylinidae, Pselaphinae) from Georgia, Zootaxa 4608 (2), pp. 371-379 : 372-378

Bergrothia barbakadzei Maghradze, Faille, Barjadze & Hlaváč sp. nov.

( Figs 7–22 )

Material examined: Holotype, ♁: GEORGIA, Imereti region, Sataplia–Tskaltubo karst massif, Datvis Cave , dark zone, 05.vii.2018, E. Maghradze leg. ( SMNS) . Paratypes (6♁♁, 6♀): same data as holotype, 1♁ ( IZISU) , 1♁ ( CPH) and 1♀ ( NMPC) ; same data as holotype, but 26.v.2018, 1♀ and 1♁, ( IZISU) ; same data as holotype, but 29.vii.2018, 1♀, ( IZISU) ; same data as data as holotype,but 03.ix.2018, 1♁ ( SMNS) ; same data as holotype, but 28.ix.2018, 1♁, ( NMPC) and 1♀ ( CPH) ; GEORGIA, Imereti region, Sataplia–Tskaltubo karst massif, Prometheus Cave , dark zone, 05.vii.2018, 1♁, E. Maghradze leg. ( CPH) ; GEORGIA, Imereti region, Sataplia–Tskaltubo karst massif, Melouri Cave , dark zone, 1♀, 12.v. 2018, A. Faille leg. ( SMNS) ; same data, but 26.v.2018, E. Maghradze leg., 1♀ ( SMNS) .

Description. Body length, male: 2.75–3.02 mm, female: 2.80–2.83 mm; combined width of elytra, male: 0.76– 0.77 mm, female: 0.75–0.79 mm; colour reddish–brown, slightly shiny, whole body covered with golden setae ( Figs 7–8 ).

Head ( Figs 9, 13 ) slightly elongate, about 1.2 times as long as wide, surface between lateral carinae rough ( Fig. 9 ); lateral vertexal carinae well–defined, reaching antennal tubercles at level of vertexal foveae and gradually weakening posteriorly; medial carina originating almost at level of constriction between head capsule and neck, and extending anteriorly to frontal excavation. Frontal excavation well–developed between U–shaped supraantennal tubercles; vertexal foveae naked and deep, located on each side of medial carina at midlength of it; lateral and ventrolateral setae long, 1.5–2.9 times longer than dorsal setae on frons and vertex; eyes strongly reduced, consisting of 3–4 small, pale ommatidia; clypeus large, rounded; lateral carinae from antennal tubercles to the middle of clypeus forming an angle of approximately 90°, lateral carinae of clypeus well–developed and reaching ocular spines; mandible stout, with five teeth; maxillary palpi ( Fig. 13 ) small, shorter than head; palpomere I minuscule, ca. 0.20 times as long as palpomere II; palpomere II long and thickened distally, palpomere IV 2.12–4.00 times longer than palpomere III and 0.75–1.41 times longer than palpomere II. Dorsolateral sides of palpomere IV with three, well–defined sensillae ( Figs 10, 10a ).

Antennae ( Fig. 11 ) long and slender; male: 1.47–1.52 mm; female: 1.48–1.59 mm; all antennomeres longer than wide; scape and pedicel of subequal length, scape about 1.3 times as long as wide, pedicel about twice as long as wide; antennomere XI longer and thicker than all remaining antennomeres, 2.4 times as long as wide ( Fig. 12 ).

Pronotum ( Fig. 14 ) rounded at sides, about 1.1–1.2 times as long as wide; widest near middle, in middle about 1.4 times wider than anterior margin and 1.3 times wider than posterior margin; with median depression, four small antebasal foveae and well–defined lateral foveae; basal third of pronotum bearing pair of spine–like projections ( Fig. 14 ).

Elytra ( Fig. 15 ) smooth, slightly shorter than abdomen, 0.65–0.74 times as long as all visible abdominal tergites, slightly wider than long, about 1.3 times as long as pronotum; posterior margin truncate, posterolateral angle round; dorsally moderately convex; with three well–defined and deep basal foveae; suture well–defined.

Abdomen ( Figs 17, 18 ) about 1.2 times longer than wide, about as wide as elytra; first visible tergite (IV) lacking basal carinae, about 1.5 times as wide as long, with wide, setose basal depression and two well–defined oblique lateral carinae; second and third visible tergites (V–VI) subequal in length, fourth visible tergite (VII) about 1.7 times as long as second (V) and third (VI) visible tergites and more than twice as long as fifth visible tergite (VIII).

Legs short and slender, profemora bearing row of small and curved prone setae along subapical carinae. mesotrochanters of males with thick and strong tooth ( Fig. 16 ), mesotibiae with small spur in apical third in male ( Fig. 19 ).

Aedeagus asymmetrical, as in Figs 21–22 .

Sexual dimorphism. Mesotrochanters of male with thick and strong tooth ( Fig. 16 ); in females simple, lacking tooth. Mesotibia with small spur on apical third in males ( Fig. 19 ); in females simple, lacking tooth ( Fig. 20 ).

Differential diagnosis. The new species strongly resembles B. mingrelica by head roughness between lateral carinae, first visible abdominal tergite (IV) shorter than elytra, aedeagus with a dorsoapical brush of setae, and by a similar body size. The new species differs from B. mingrelica in the lack of a dorsobasal brush of setae on aedeagus ( Figs 21–22 ), which is present in B. mingrelica ( Fig. 23 ) and the presence of pale and small ommatidia, while B. mingrelica has dark and well–developed ones.

Etymology. Patronymic, dedicated to Mr. Valeri Barbakadze, Georgian speleologist and cave diver, who helped us during the expeditions in the caves.

Ecology. The new species was collected on guano, under plant debris and stones as well as on wet walls in dark zones of Prometheus, Datvis and Melouri caves. The presence of eyes suggests that it is a troglophilic species.

Distribution: The species is apparently endemic to Georgia, Imereti region, Tskaltubo district, Sataplia–Tskal-tubo karst massif.

Figures

FIGURES 7–8. Bergrothia barbakadzei sp. nov., habitus 7, dorsal view (female); 8, ventral view (male).

FIGURES 9–14. Bergrothia barbakadzei sp. nov. 9, head, dorsal view (female); 10, head dorsal view with (10a) sensilla on segment IV of maxillary palpus (female); 11, antenna (female); 12, antennal segment XI (female); 13, head, ventral view (male); 14, pronotum, dorsal view (female).

FIGURES 15–18. Bergrothia barbakadzei sp. nov. 15, elytra (female); 16, median leg (male); 17, abdominal tergites II–VII, dorsal view (female); 18, abdominal tergites II–VII, ventral view (male).

FIGURES 19–23. Mesotibiae of Bergrothia barbakadzei sp. nov. (scale bar: 250 μm). 19, male; 20, female; aedeagus of Bergrothia barbakadzei sp. nov. 21, lateral view (scale bar: 200 μm); 22, dorsal view (scale bar: 200 μm); aedeagus of Bergrothia mingrelica (Reitter). 23, dorsal view (Reitter) (scale bar: 200 μm). Redrawn from Hlaváč, 1999.