Mesolestes (Mesolestes) niger, Felix, 2017

Felix, Ron F. F. L., 2017, New species and new distributional data on Carabidae (Coleoptera) from the Socotra Archipelago, Acta Entomologica Musei Nationalis Pragae (Acta. Ent. Mus. Natl. Pragae) 57, pp. 41-54 : 50-51

Mesolestes (Mesolestes) niger sp. nov.

( Figs 11, 12 )

Type locality. Yemen, Socotra Island, Hagher Mts, Wadi Madar, 12°33.2ʹN, 54°00.4ʹE.

Type material. HOLOTYPE: J ( NMPC), Yemen, Socotra Island, Hagher Mts , Wadi Madar, 12°33.2ʹN, 54°00.4ʹE, 1170 m, 18.vi.2012, Socotra expedition 2012, J. Bezděk, J. Hájek, V. Hula, P. Kment, I. Malenovský, J. Niedobová & L. Purchart leg. PARATYPES: 1 ♀, same data ( NMPC) ; 2 JJ 4 ♀♀, Hagher Mts. , Skand Mt. env., 12°34.6ʹN, 54°01.5ʹE, 1450 m, 16.–18.vi.2012, Socotra expedition 2012, J. Bezděk, J. Hájek, V.Hula, P. Kment, I. Malenovský, J. Niedobová & L. Purchart leg.( NMPC, RFBE) ; 1 ♀, same data, 12.–13.xi.2010, J. Bezděk leg. ; 1 ♀, same data, J. Hájek leg. ( NMPC) ; 1 ♀, same data, P. Hlaváč leg. ( NMPC) ; 1 ♀, 12°34.557ʹN, 54°01.514ʹE, 7.–8.vi.2010, V. Hula & I. Niedobová leg. ( NMPC) .

Description of holotype. Body length 2.6 mm. Apterous.

Colour. Head, pronotum, elytra and epipleura, and whole underside uniformly black without any ligther trace except for labrum dark brown with lighter margins ( Fig. 11 ). Mandibles brownish-testaceous, with lighter apex. Antennae testaceous with antennomeres I–III partly darker. Tarsomeres and tibiae and knees yellow, femora infuscated.

Sculpture and structures. Head and pronotum with distinct isodiametric microsculpture. Elytra more shiny than pronotum, microsculpture transverse meshes.

Anterior margin of labrum regularly rounded, with six setae. Clypeus with straight anterior margin and two setae. Maxillary palpomeres smooth, penultimate labial palpomere with two setae. Eyes flat. Temples long, oblique. Antennae pubescent from III on. Mental tooth absent.

Anterior margin weakly concave. Front angles barely protruding. Lateral marginal gutter very narrow and fine. Anterior lateral setae at widest part of pronotum, basal lateral setae just before posterior angles. Median furrow fine. Basal furrows absent.

Striae very shallow, even weaker towards sides, vanished at apex. Intervals almost flat. Marginal gutter very narrow and fine. Basal margin broadly rounded and almost straight towards scutellum. Prescutellar pores present but no scutellar striae. Two punctures in interval III.

Legs. Protarsomeres widened. Apical metatarsomere almost as long as III plus IV, with two pairs of bristles underneath; metatarsomere I as long as II plus III.

Aedeagus, see Fig. 12 .

Variability. There is no variation within the specimens of the type series, except in body length ranging between 2.6–2.8 mm.

Differential diagnosis. Based on the characteristically shaped apex of the aedeagus and pubescence of antennae beginning with antennomere III, the new species can be attributed to the subgenus Mesolestes s. str. Mesolestes s. str. species are found in western Mediterranean and Middle East, southern Asia and continental Africa and Madagascar.

There are no black Mesolestes s. str. known in the regions adjacent to Socotra. All species are Mediterranean and/or are bi-coloured, like M. scapularis abyssinicus Mateu, 1960 from Ethiopia. The only black species, M. fuscus Mateu, 1956 , occurs in Lebanon. The new species fits in general the description of the latter M. fuscus which is also apterous, however, the aedeagus ( Fig. 12 ) is slightly different from that of M. fuscus as depicted by MATEU (1956). Because both species are apterous, the slight difference in aedeagus, the huge gap between Lebanon and Socotra without any known Mesolestes s. str. and the rather isolated position of the Archipelago, it seems right to designate the taxon of Socotra a new species, although the type of M. fuscus was not seen.

Etymology. The specific epithet, the Latin adjective niger (- a, - um), refers to the overall black colour of the new species.

Collection circumstances. Sifted in montane shrubland with dominant Cephalocroton socotranus (Balf. f.) Pax ( Euphorbiaceae ).

Distribution. A species endemic to Socotra Island.

Figures

Figs 7–12. 7 – Glycia socotrana sp. nov., female stylomeres. 8–10 – Apristus dioscoridus sp. nov.; 8 – habitus; 9 – median lobe of aedeagus is lateral view; 10 – female stylomeres. 11–12. Mesolestes niger sp. nov. 11 – habitus; 12 – median lobe of aedeagus is lateral view. Not in scale.