Limnebius dioscoridus, Jäch & Delgado, 2012

Jäch, Manfred A. & Delgado, Juan A., 2012, Limnebius dioscoridus sp. nov. from Socotra Island (Coleoptera: Hydraenidae), Acta Entomologica Musei Nationalis Pragae 52, pp. 131-134 : 131-134

Limnebius dioscoridus sp. nov.

( Figs. 1–3, 6–10 )

Type locality. Permanent river in mountain valley with granite and limestone slopes, Wadi Ayhaft, 12°36.5′N 53°58.9′E, 200 m a.s.l., Hagier (= Hagghir) Mts., northern Socotra Island, Yemen (see also FIKÁČEK et al. 2012: Fig. 7 ).

Type material. HOLOTYPE: ♁ ( NMPC), ‘ YEMEN, Socotra Island wadi Ayhaft 12°36.5′N 53°58.9′E, 200 m Jiří Hájek leg. 7-8.xi.2010 ’. PARATYPES: 26 specimens ( MNCN, NMPC, NHMW), same locality label as holotype [three of four MNCN paratypes presently remain in absolute ethanol, with locality label inside and the reference number

HÁJEK J. & BEZDĚK J.(eds.): Insect biodiversity of the Socotra Archipelago. Acta Entomologica Musei Nationalis Pragae 52 (supplementum 2): i–vi + 1–557.

‘RA728’ written outside with a permanent marker. The fourth specimen, a female, was extracted, mounted dry on a white label and pinned, with one wing removed and mounted in a separate permanent preparation. Both the pinned specimen and the wing have an additional label ‘DNA ex., IBE-RA728’]; 3 specimens ( NMPC): ‘ YEMEN: Socotra Isl. Hallah Arhar (spring) 12°33.0′N 54°27.6′E, 15m 11.xi.2010, leg. J. Bezděk’ .

Diagnosis. Habitus as in Fig. 1 . Limnebius dioscoridus sp. nov. is a member of the L. atomus species group (sensu JÄCH 1993). It is very similar and very closely related to L. arabicus Balfour-Browne, 1951 ( Yemen and Israel) and L. pararabicus Jäch & Delgado, 2010 ( UAE).

Externally, it agrees with these species in general appearance incl. body length: 0.80–1.05 mm. Surface of pronotum smooth and glabrous, very sparsely and superficially micropunctate. Elytral margins gently rounded, less parallel than in L. myrmidon Rey, 1883 . Elytral surface smooth or very faintly microreticulate anteriorly, more or less distinctly microreticulate posteriorly.

Aedeagus ( Figs. 2–4 ): Very similar to L. arabicus ( Fig. 5 , see also JÄCH & DELGADO 2010: Figs. 9–10 ) and L. pararabicus ( Fig. 6 , see also JÄCH & DELGADO 2010: Figs. 11–12). Excision on right margin (lateral view) of main piece more distal than in the compared species, apex of main piece (dorso-lateral view) less strongly widened than in L. arabicus (ventral view); in dorso-lateral view right apical corner of main piece wider than in L. pararabicus , excision not as distinct as in L. arabicus ; ejaculatory duct very slightly projecting apically. Distal lobe longer than in L. arabicus , slightly wider than in L. pararabicus .

Gonocoxite ( Fig. 7 ) more or less as in L. pararabicus (see JÄCH & DELGADO 2010: Fig. 14); left apophysis of inner plate not projecting; cavea slightly smaller than in L. pararabicus . Tergite X ( Fig. 8 ): basal apophyses larger than in L. pararabicus ; apex with one pair of very long setae, longer than tergite. Spermatheca as in Figs. 9–10 .

Etymology. Dioscoridus (proper noun in apposition) is the Latin name for Socotra Island.

Distribution. So far known from two localities on Socotra Island, Yemen.

Figures

Figs. 1–6. Limnebius dioscoridus sp. nov. 1 – habitus; 2–3 – aedeagus (2 – ventral view, 3 – dorso-lateral view); 4–6 – aedeagal apex in ventral view (4 – Limnebius arabicus Balfour-Browne, 1951, 5 – L. pararabicus Jäch & Delgado, 2010, 6 – L. dioscoridus sp. nov.). Scale bars to Figs. 2–6: 0.05 mm

Figs. 7–10. Limnebius dioscoridus sp. nov.: 7 – gonocoxite, 8 – female tergite X, 9–10 – spermatheca. Scale: 0.05 mm.