Sibinia (Dichotychius) caldaraedicata, Colonnelli, 2014

Colonnelli, Enzo, 2014, Apionidae, Nanophyidae, Brachyceridae and Curculionidae except Scolytinae (Coleoptera) from Socotra Island, Acta Entomologica Musei Nationalis Pragae 54, pp. 295-422 : 338-339

Sibinia (Dichotychius) caldaraedicata sp. nov.

( Figs 43, 46 )

Type material. HOLOTYPE: J ( NMPC), ‘ Yemen, Socotra Island // Deiqub cave, 12.vi.2012 // cave & Croton socotranus + // Jatropha unicostata shrubland; // 12°23.1′N, 54°00.9′E, 115 m’, ‘ Socotra expedition 2012 // J. Bezděk, J. Hájek, V. Hula, // P. Kment, I. Malenovský, // J. Niedobová & L. Purchart leg.’. PARATYPES: 4 JJ 8 ♀♀, same label data as holotype (7 NMPC, 1 BMNH, 3 ECRI); 1 ♀, ‘ Yemen, Socotra Island // ca. 3 km NE of Shuab // Avicennia marina mangrove; // sand dunes, 20-21.vi.2012 // 12°34.1′N, 53°23.9′E, 3 m’, ‘ Socotra expedition 2012 // J. Bezděk, J. Hájek, V. Hula, // P. Kment, I. Malenovský, // J. Niedobová & L. Purchart leg.’ ( NMPC); 2 ♀♀, ‘ Yemen, Socotra Island // Bizidig, 13.vi.2012 // Avicennia marina mangrove; // 12°18.6′N, 53°48.2′E, 6 m’, ‘ Socotra expedition 2012 // J. Bezděk, J. Hájek, V. Hula, // P. Kment, I. Malenovský, // J. Niedobová & L. Purchart leg.’ (1 NMPC, 1 ECRI).

Description. Male holotype. Body length 1.9 mm. Brown, rostrum, femora and tibiae ferruginous, tarsi and antennal club darker. Dorsal vestiture of serrate, pale ochreous to brownish, recumbent, roundish to elliptically elongate, depressed scales, pale ones forming two vague longitudinal stripes on both sides of pronotal disc and more condensed on basal tip of pronotum, brownish ones scattered on elytra which appear somewhat spotted. Scutellum densely covered by minute milk-white scales. Scales on elytral striae similar to those on intervals which are arranged in 1-2 irregular rows. Ventral side and sides of pronotum and elytra densely clothed with similar but little smaller whitish scales ( Fig. 46 ).

Head. Rostrum slightly shorter than pronotum, regularly curved, finely and sparsely punctured, basal fifth with pale erect elongate scales. Antennae inserted at middle of rostrum; scape thin and quite abruptly clubbed; funicular antennomere I much thicker and about as long as combined length of II and III, antennomere II barely longer than III, antennomeres IV- V shorter, antennomere VII strongly transverse; club shortly fusiform, setose and about as long as preceding three antennomeres. Head globose; space between eyes wider than base of rostrum and clothed with dense, semierect, embricate, elongate ochreous scales. Eyes large and not protruding from head convexity.

Pronotum about as long as wide, with faintly rounded subparallel sides up to apical third, then moderately narrowing towards truncate apical margin; base bisinuous; disc rather flat. Scutellum rounded, flat.

Elytra 1.36 times longer than wide, disc almost flat, maximum width at apical third; sides almost straight and barely diverging from moderately protruding humeri up to apical third and then quite strongly jointly curved towards apex; preapical calli feeble. Striae formed by slightly elongate rectangular quite shallow punctures completely hidden by scales. Interstriae slightly wider than striae, flat.

Legs thin; femora moderately clubbed, edentate, clothed by moderately dense almost recumbent milk-white scales; tibiae almost straight; tarsi moderately elongate, tarsomere IV a little longer than combined length of two preceding ones; claws simple.

Ventral side. Abdominal ventrites I and II flat, remaining ones quite convex.

Variability. The vestiture, as often occurs in this genus, is quite variable in the colour, size and form of the scales, which can be more elongate than in the holotype and somewhat sulcate, whereas the colour of some specimen is slightly paler or darker than in the holotype. Females differ by their slightly longer and thinner rostrum, and abdomen uniformly convex.

Male genitalia. Aedeagus as depicted in Fig. 43 .

Body length 1.9–2.2 mm.

Differential diagnosis. General shape and clothing, in addition to simple claws, make this species quite similar only to Sibinia exigua Faust, 1885 from western Mediterranean, and more so to S. subirrorata Faust, 1885 distributed from southeastern Russia to United Arab Emirates ( CALDARA 2013). The new species is however easily differentiated from S. exigua , although the aedeagus is rather similar to that of this one, by its colour not uniformly milk- -white, clearly more elongate body shape and scales much larger and more strictly appressed. From the close S. subirrorata the new species is immediately separated by its rostrum not scaled beyond the basal middle, scales concave or sulcate instead of flat, and apex of aedeagus rounded instead of sharp.

It is worthy to note that the other three Sibinia Germar, 1817 besides S. subirrorata cited by CALDARA (1993a, 2013) from the Arabian Peninsula, namely S. modesta Desbrochers, 1895 , Sibinia fusca Tournier, 1874 and S. reichei Tournier, 1873 , have appendiculate claws and cannot be confused with the new species. The Palaeotropical Sibinia , almost all South African ( CALDARA 1989, 1993b), are included in species groups very different from the subgenus Dichotychius Bedel, 1885 to which S. caldaraedicata sp. nov. is assigned.

Etymology. The species is named after my friend, the outstanding taxonomist Roberto Caldara, who revised the Palaearctic and Ethiopian Sibinia , by combining his family name with the Latin word for ‘dedicated to’ into a composite adjective caldaraedicatus (- a, - um).

Distribution. Endemic to Socotra Island.

Figures

Figs 40–47. 40, 42 – Mesoxenomorphus rugipennis sp. nov.: 40 – habitus of the holotype; 42 – aedeagus of a paratype in dorsal view. 41 – Mesoxenomorphus africanus Wollaston, 1873 from South Africa, Port Elizabeth, habitus. 44–45 – Mechistocerus inornatus sp. nov. 44 – habitus of the holotype; 45 – aedeagus of a paratype in dorsal view. 43, 46 – Sibinia caldaraedicata sp. nov.: 43 – aedeagus of a paratype in ventral view; 46 – habitus of the holotype.