Geostiba (Sibiota) granisuturalis, Assing, 2017

Assing, Volker, 2017, A revision of Geostiba of the West Palaearctic region. XXV. New species from Georgia and Greece, and additional records (Coleoptera: Staphylinidae: Aleocharinae), Linzer biologische Beiträge 49 (2), pp. 1093-1106 : 1102-1104

publication ID

http://doi.org/10.5281/zenodo.5183162

persistent identifier

http://treatment.plazi.org/id/EC5FB208-9E0A-5774-E084-5B4DFE65C7BE

treatment provided by

Felipe

scientific name

Geostiba (Sibiota) granisuturalis
status

nov.sp.

Geostiba (Sibiota) granisuturalis   nov.sp. ( Figs 19-26 View Figs 19-26 , Map 2 View Map 2 )

T y p e m a t e r i a l: Holotype 3: "N 43°06'15 E 42°35'50 (12), Georgien Svaneti , Mazeri 1660 m, Brachat & Meybohm, 26.6.2017 / Holotypus 3 Geostiba granisuturalis   sp. n. det. V. Assing 2017 " (cAss)   . Paratypes: 13, 2♀♀: same data as holotype (cAss)   ; 533, 9 ♀♀: "N 43°01'20 E 42°45'00 (14), Georgien Svaneti Mestia-Hatsvali Bergstaion [sic] 2350 m, Brachat & Meybohm, 27.6.2017 " (cAss)  

E t y m o l o g y: The specific epithet (adjective) alludes to the granulosely punctured suture of the male elytra.

D e s c r i p t i o n: Body length 1.9-2.4 mm; length of forebody 0.9-1.0 mm. Coloration: body dark-yellowish to reddish-yellow. Eyes reduced to minute rudiments without pigmentation and without ommatidia. Pronotum without impressions on either side of midline. Hind wings completely reduced.

3: elytra with weakly to moderately elevated suture, this elevation broader anteriorly than posteriorly, along suture with granulose punctures, disc more or less distinctly impressed; tergite VII ( Fig. 19 View Figs 19-26 ) with median pair of short parallel carinae posteriorly; posterior margin of tergite VIII convex, with small concavity in the middle; posterior margin of sternite VIII obtusely produced posteriorly; median lobe of aedeagus ( Figs 20- 23 View Figs 19-26 ) 0.27-0.29 mm long, without distinct flagellum and without semi-transparent spines in internal sac; paramere not distinctive.

♀: posterior margin of tergite VIII broadly convex, very shallowly concave to truncate in the middle; posterior margin of sternite VIII shallowly concave in the middle; distal portion of spermatheca ( Figs 24-26 View Figs 19-26 ) not distinctly dilated.

C o m p a r a t i v e n o t e s: Among the Sibiota   species known from the Greater Caucasus, G. granisuturalis   is characterized by the combination of reduced eyes without ommatidia and pigmentation, relatively weakly elevated suture of the male elytra, and the primary sexual characters. It differs from G. recta ASSING, 2016   , the only other representative of the subgenus recorded from Svaneti, by paler coloration, smaller body size, less pronounced microsculpture on the forebody, the absence of distinct sutural carinae on the male elytra, shorter and parallel carinae on the male tergite VII, an aedeagus with a curved ventral process (lateral view), with a crista apicalis of different shape, and without a long flagellum in the internal sac, as well as by a proximally undilated spermatheca.

To account for the new species the key to the Sibiota   species of the Caucasus region in ASSING (2016b) is modified as follows:

4. Male elytra with conspicuously elevated and narrow sutural carinae. Male tergite VII with median pair carinae strongly converging posteriorly (PACE 1995: figure 89). Median lobe of aedeagus with ventral process obtusely angled in lateral view (PACE 1995: figure 90). Spermatheca with undilated distal portion and with long and slender proximal portion (PACE 1996: figure 94). Distribution: West Georgia: environs of Batumi ( Map 1 View Map 1 ) ........................................................................................ batumiensis PACE  

- Male elytra with less elevated and broader sutural carinae or elevation. Male tergite VII with median pair of carinae subparallel or weakly converging posteriorly .......................4a

4a. Sutural portion of male elytra weakly to moderately elevated, this elevation with row of granulose punctures on either side of suture; male tergite VII with median pair of short parallel carinae posteriorly ( Fig. 19 View Figs 19-26 ). Median lobe of aedeagus and spermatheca as in Figs 21-26 View Figs 19-26 . Distribution: Georgia: Svaneti ( Map 2 View Map 2 )........................... granisuturalis nov.sp.

- Sutural portion of male elytra (in large male) more strongly elevated. Primary sexual characters of different shapes. Unknown from Svaneti .......................................................5

D i s t r i b u t i o n a n d n a t u r a l h i s t o r y: Thespecimenswerecollected in two localities in Svaneti ( Map 2 View Map 2 ) by sifting leaf litter in a valley with alder, hazelnut, and fir, and in a birch forest with dense herb undergrowth (MEYBOHM pers. comm.) at altitudes of 1660 and 2350 m.

T

Tavera, Department of Geology and Geophysics

V

Royal British Columbia Museum - Herbarium