Socotralabis bezdeki, Kočárek, 2014

Kočárek, Petr, 2014, Earwigs (Dermaptera) of Socotra Island: checklist, distribution, and description of a new genus and four new species, Acta Entomologica Musei Nationalis Pragae 54, pp. 1-21 : 7-9

Socotralabis bezdeki sp. nov.

( Figs 6–10 , 29 )

Type locality. Yemen, Socotra Island, Hagher Mts., Scand Mt., 12°34.6′N, E54°01.5′ E, 1,450 m a.s.l.

Material examined. HOLOTYPE: J, ‘ Yemen Socotra Island / Hagher Mts. , Scand Mt. env. / montane evergreen woodland / 16.-18.vi.2012 / 12°34.6′N, E54°01.5′ E, 1450 m // Socotra expedition 2012 / J. Bezděk, J. Hájek, V. Hula, P. Kment, I. Malenovský, J. Niedobová & L. Purchart lgt. // HOLOTYPUS / Socotralabis / bezdeki sp. nov. / det. P. Kočárek 2013 ’ ( NMPC). PARATYPES: 1 J 8 ♀♀, same label data as holotype ( MMBC, NMPC, PKCO). Each of the paratype specimens is provided with an additional printed red label: ‘ PARATYPUS / Socotralabis / bezdeki sp. nov. / det. P. Kočárek 2013 ’.

Description. Male. Body brown to blackish brown, shiny; antennae unicolour; pronotum brown to blackish brown with paler sides; legs yellowish brown; forceps reddish brown. Cuticle punctured, shiny; tegmina and wings entirely absent.

Head ( Fig. 6 ) as long as wide, postfrontal and coronal sutures very fine, but distinct; frons convex, posterior margin of head feebly emarginate in middle. Eyes blackish brown, approximately 0.5 times as long as length of head posterior to eyes. Antennae pubescent, with 20 antennomeres (in holotype incomplete); antennomere 1 long, narrowed basally, widened terminally, as long as length of antennomeres 2–4 combined; antennomere 2 transverse, as long as wide; antennomere 3 longer than antennomere 4. Antennomeres 2–3 cylindrical, other antennomeres conical.

Pronotum ( Fig. 6 ) smooth, about as long as broad, widened posteriorly; margins nearly straight with rounded corners. Median sulcus fine but distinct. Meso- and metanotum transverse, smooth; mesonotum truncate posteriorly, metanotum broadly emarginate. Median sulcus visible on mesonotum, on metanotum absent. Sternal plates typical for genus. Legs comparatively long, yellowish brown; femora stout; tibiae with thick and fine setae; metatarsi with metatarsomere 1 slightly longer than length of metatarsomeres 2–3 combined.

Abdomen ( Fig. 6 ) sparsely regularly punctulate; tergites (except for ultimate tergite) convex, slightly widened posteriorly; lateral glandular folds invisible; antero-lateral parts of tergites with pairs of small longitudinal smooth areas; posterior margins of all tergites smooth, without keels or striation. Ultimate tergite transverse, sides convex, narrowed posteriorly, with shallow median longitudinal furrow; posterior margin in middle straight. Penultimate sternite narrowed posteriorly, with posterior margin concave ( Fig. 7 ). Pygidium flat. Forceps slightly asymmetrical, right branch little more curved in posterior half than left one; both branches remote and stout at base, gradually tapering apically, almost straight in basal two thirds, both slightly incurved afterwards, apices gently hooked, inner margin finely crenulated, dorsally trigonal in basal half, cylindrical posteriorly.

Genitalia ( Figs 9, 10 ) with parameres short, 1.8 times longer than broad, broadened in middle and narrowed apically, external apical angle and margin convex, tip with remarkable incision in middle ( Fig. 10 ). Incision of parameres situated at interface of inner and outer membrane, median membrane extending to deepest part of incision. Longer genital lobe 1.6 times longer than length of paramere ( Fig. 9 ).

Female. Agrees with male in most characters except for: penultimate sternite gradually narrowed posteriorly, with posterior margin rounded; ultimate tergite comparatively narrowed posteriorly with posterior margin slightly emarginated; forceps with branches contiguous, simple and straight, inner margin finely crenulated ( Fig. 8 ).

Measurements. Total body length without forceps: JJ: 10.6–11.4 mm, holotype 14.8 mm; ♀♀: 11.0– 12.1 mm. Length of forceps: JJ: 1.8–1.9 mm, holotype 1.9 mm; ♀: 1.8–2.2 mm.

Differential diagnosis. Socotralabis bezdeki sp. nov. differs from S. hulai sp. nov. in the following combination of characteristics: S. bezdeki sp. nov. is a more slender species with the abdomen nearly parallel sided and not remarkably widened posteriorly; tergites 7–9 are smooth, not rugoso-striated at the sides; the parameres of the male genitalia are slender and they are two times longer than wide.

Etymology. The species is named after one of its collectors, Jan Bezděk (Brno, Czech Republic) as thanks for kind collecting earwigs for my studies.

Bionomy. Sifted from wet leaf litter in a montane evergreen woodland, association Leucado hagghierensi-Pittosporetum viridiflorum.

Distribution. Yemen, Socotra Island ( Fig. 29 ). Most likely an endemic species.

Figures

Figs 6–10. Socotralabis bezdeki sp. nov. 6 – habitus of male holotype; 7 – male penultimate sternite, ventral view; 8 – ultimate tergite and forceps of female paratype; 9 – male genitalia; 10 – right paramere of male genitalia.

Figs 27–29. Sketch maps of Socotra Island displaying the known and newly recorded distribution of Dermaptera. Published records are based on HAAS at al. (2004); the occurrence of Labidura riparia (Pallas, 1773) on Samha Island published by these authors is not displayed.