Geostiba (Tropogastrosipalia) defecta, Assing, 2018

Assing, Volker, 2018, A revision of Geostiba of the West Palaearctic region. XXVI. New species and additional records, primarily from the Caucasus region (Coleoptera: Staphylinidae: Aleocharinae), Linzer biologische Beiträge 50 (2), pp. 1033-1054 : 1038-1039

Geostiba (Tropogastrosipalia) defecta nov.sp. ( Figs 6-11 ; Map 1 )

T y p e m a t e r i a l: Holotype ♂: "RU - Krasnodar area, Lazarevskoye distr., Soloniki env., 550 m, leaf litter, 4.VI.2017, leg. Gontarenko / Holotypus ♂ Geostiba defecta sp. n. det. V. Assing 2019" (cAss) . Paratypes: 4♂♂, 3♀♀: same data as holotype (cAss, Gon) ; 1♀: same data, but 430 m (cGon) .

E t y m o l o g y: The specific epithet is the past participle of the Latin verb deficere (to lack) and alludes to the near absence of modifications of the male pronotum, elytra, and abdomen, as well as to the completely absent cristal process of the aedeagus.

D e s c r i p t i o n: Body length 2.5-3.0 mm; length of forebody 1.0- 1.2 mm. Habitus as in Fig. 6 . Coloration: head reddish to black; pronotum and elytra reddish to darkbrown; abdomen reddish to dark-brown with tergites V-VI and the anterior portion of VII blackish; legs yellowish; antennae reddish to dark-brown with the basal two antennomeres more or less distinctly paler.

Head and pronotum with microreticulation and with moderately dense and very fine punctation. Pronotum approximately as broad as long. Abdomen large and broad, distinctly broader than elytra; posterior margin of tergite VIII with or without fine rudiment of a palisade fringe.

♂: pronotum and abdomen unmodified; elytra with granulose punctation and with shal-

low impression in postero-lateral portion; median lobe of aedeagus ( Figs 7-9 ) 0.27-0.28 mm long, without cristal process.

♀: elytra with fine non-granulose punctation, with or without very indistinct impression in postero-lateral portion; spermatheca as in Figs 10-11 , not distinctive.

C o m p a r a t i v e n o t e s: Despite the absence of modifications of the male abdomen, G. defecta belongs to the subgenus Tropogastrosipalia , as can be inferred not only from the habitus, but especially from the characteristic shape of the spermatheca. The species is distinguished from all other Tropogastrosipalia species by the unmodified male abdomen alone, from most of them also by the unmodified male pronotum and the weakly modified male elytra without sutural carinae, without lateral edges or elevations, and without pronounced impressions. The only other Tropogastrosipalia species with a completely reduced cristal process of the aedeagus is G. perdita ASSING, 2017, an endemic of the Greek island Ikaría, which differs from the new species by sexually dimorphic pronotum, a more slender abdomen, and the presence of a postero-median spine on the male tergite VII. For illustrations of G. perdita see ASSING (2017b).

D i s t r i b u t i o n: The type locality is situated near Soloniki (43°53'N, 39°22'E) to the southeast of Lazarevskoye (Krasnodarskiy Kray: SE Tuapse) in the western extension of the West Caucasus ( Map 1 ). The specimens were sifted from leaf litter at altitudes of 430 and 550 m.

Figures

Map 1: Distributions of the species of the subgenus Tropogastrosipalia in the Caucasus region, based on examined records: G. reducta (black star); G. defecta (black diamond); G. svanetica (white square); G. gibberiventris (black square); G. tiflisensis (white diamonds); G. artvinensis (white circles); G. pontica (black triangle); G. solodovnikovi (white triangle); G. priva (white star); G. khnzoriani (black circles).

Figs 1-6: Geostiba reducta nov.sp. (1-5) and G. defecta (6): (1) male forebody in dorsal view; (2) male forebody in lateral view; (3) male tergites VI-VII in lateral view; (4-5) median lobe of aedeagus in lateral and in ventral view; (6) habitus. Scale bars: 6: 1.0 mm; 1-3: 0.5 mm; 4-5: 0.1 mm.

Figs 7-14: Geostiba defecta nov.sp. (7-11) and G. articarinata (12-13): (7-9, 12) median lobe of aedeagus in lateral and in ventral view; (10-11, 14) spermatheca; (13) female sternite VIII. Scale bars: 0.1 mm.