Geostiba (Sibiota) uniplicata, Assing, 2011

Assing, V., 2011, A revision of Geostiba of the West Palaearctic region. XXI. Eight new species from Turkey and the Caucasus, a new synonymy, and additional records (Coleoptera: Staphylinidae: Aleocharinae), Linzer biologische Beiträge 43 (2), pp. 1135-1158 : 1150-1153

Geostiba (Sibiota) uniplicata nov.sp. ( Figs 38-46 )

T y p e m a t e r i a l: Holotype: "RU [8], W-Caucasus, 15 km ENE Krasnaya Polyana, 2040 m, 43°43'06''N, 40°22'55''E, 16.VII.2011, V. Assing / Holotypus Geostiba uniplicata sp.n. det. V. Assing 2011" (cAss). Paratypes: 1, 1: same data as holotype (cAss).

D e s c r i p t i o n: Body length 2.2-2.4 mm. Habitus as in Fig. 38 . Coloration: whole body dark-yellowish.

Head approximately as broad as long ( Figs 39-40 ); punctation extremely fine, barely noticeable; interstices with very shallow microsculpture and glossy. Eyes not projecting from lateral contours of head, small, 1/5-1/4 as long as postocular region in dorsal view,

composed of approximately five ommatidia, and with pigmentation. Antenna distinctly and gradually incrassate apically, antennomere X approximately twice as wide as long.

Pronotum 1.10-1.15 times as wide as long and 1.15-1.20 times as wide as head ( Figs 39- 40 ), without sexual dimorphism; punctation extremely fine, barely noticeable; interstices with distinct microreticulation.

Elytra with pronounced sexual dimorphism, 0.65-0.70 times as long as pronotum ( Figs 39-40 ); interstices with pronounced microreticulation and almost matt. Hind wings absent.

Abdomen wider than elytra; punctation very fine and sparse, barely noticeable; interstices with shallow microreticulation; tergite VII with sexual dimorphism; posterior margin of tergite VII without palisade fringe; posterior margin of tergite VIII broadly convex in both sexes.

: elytra with suture forming a sharp carina extending from apex of scutellum to posterior margin, disc shallowly and extensively impressed; abdominal tergite VII with distinctly elevated, posteriorly acute, dorsally flattened and smooth, oblong median tubercle in posterior half ( Fig. 41 ); sternite VIII broadly convex; median lobe of aedeagus approximately 0.23 mm long, internal sac without spines ( Fig. 42 ); paramere with moderately slender apical lobe with one long and several shorter setae ( Figs 43-44 ).

: elytra without impressions and carina, with pronounced microreticulation; posterior margin of sternite VIII weakly convex, without distinct concavity in the middle; spermatheca stout, proximal portion of capsule of helicoid shape ( Fig. 45 ).

E t y m o l o g y: The specific epithet (Latin, adjective: with one fold) alludes to the presence of only one tubercle on the male abdominal tergite VII.

C o m p a r a t i v e n o t e s: Geostiba uniplicata is distinguished from the geographically close G. krzysztofi , with which it shares a similar morphology of the spermatheca, by numerous characters, particularly its slightly smaller size and paler coloration, the more pronounced microsculpture of the pronotum and the elytra, the narrower, sharper, and more elevated sutural carina on the male elytra, the completely different modifications of the male tergite VII, the shape of the male tergite VIII ( G. krzysztofi : posterior margin concave in the middle), and the different morphology of the primary sexual characters. For illustrations of G. krzysztofi see ASSING (2005). In the key in ASSING (2009), G. uniplicata would key out at couplets 133-134 together with G. flava and G. rhilensis . In order to account for the new species, the key is modified as follows:

133 Coloration of body usually more or less yellowish to yellowish-red.: tergite VII with distinct smooth, broad, oblong median elevation. Subgenus Sibiota (partim)....134

- tergite VII unmodified or with small subcircular median tubercle near posterior margin........................................................................................................................135

134: elytra on either side of suture with broader, long oblique elevation; abdominal tergite VII in posterior half with less well-defined smaller elevation or tubercle; median lobe of aedeagus and apical lobe of paramere as illustrated by PACE (1983: figures 45, 46, 48).: spermatheca with long and slender duct (PACE 1983: figure 47). Bulgaria ( ASSING 2005: map 11) .................................... G. rhilensis (RAMBOUSEK)

-: elytra with suture forming a narrow carina; abdominal tergite VII with larger, more strongly elevated, and more well-defined oblong tubercle.: spermatheca with shorter duct. Distribution different................................................................... 134a

134a Elytra with pronounced microreticulation and almost matt.: elytral carina sharper and more strongly elevated ( Fig. 39 ); abdominal tergite VII in posterior half with shorter tubercle; median lobe of aedeagus and apical lobe of paramere as in Figs 42- 44 .: spermatheca conspicuously stout ( Fig. 45 ). West Caucasus: Psheashkha range............................................................................................... G. uniplicata nov.sp.

- Elytra with shallow microreticulation and somewhat glossy.: elytral carina less sharp and less strongly elevated; abdominal tergite VII with larger, more strongly elevated, and more well-defined oblong tubercle; aedeagus as illustrated by ASSING (2000: figures 1-3).: spermatheca with shorter duct ( ASSING 2000: figures 4-5). Southeastern Austria, Slovenia........................................................... G. flava (KRAATZ)

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: Thetypelocalityissituatedin the Psheashkha range to the east northeast of Krasnaya Polyana in the West Caucasus. The specimens were sifted from moist leaf litter of a subalpine birch and maple forest at an altitude of 2040 m ( Fig. 46 ).

Figures

Figs 38-45: Geostiba uniplicata nov.sp. (38-39, 41-44: holotype): (38) male habitus; (39) male forebody; (40) female forebody; (41) male abdominal tergites V-VIII in dorsal view; (42) median lobe of aedeagus in lateral view; (43) paramere; (44) apical lobe of paramere; (45) spermatheca. Scale bars: 38: 1.0 mm; 39-40: 0.5 mm; 41-43: 0.1 mm; 44-45: 0.05 mm.

Fig. 46: Type locality of Geostiba uniplicata nov.sp.