Methods:

A usual beetle sifter (grid diameter 7 mm) was used for collecting and the extraction method applied follows Germann (2014).

The pictures of the habitus and the genital structures were made with a 5-megapixel digital camera (Leica DFC425) under a stereomicroscope (Leica MZ16). The pictures are composites processed using the software Imagic Image Access (version 12) and then retouched using Adobe Photoshop version 10.0.1 (Adobe Systems Incorporated).

The measurements of lengths and widths (L/W) are mean values and were always taken at the longest and/or widest point. The size was taken without rostrum, from the fore margin of the eyes to the elytral apex.

Label texts are cited verbatim in quotation marks. Data from different labels are separated by a double slash (//). Additional remarks to label data are set in square brackets ([ ]).

Specimens (females) of O. formaneki Reitter, 1913 used here for comparison with the new species are labelled as follows: “26.06.2003 NW Turkey, Hatip env. [environment], SW Sinop, leg. P. Białooki” (cPB).

Description

Male: body length 5.2-5.9 mm (holotype 5.3 mm); entirely dark-brown; covered with precisely recumbent (including elytral apical declivity) dark and light brown scales forming unclear maculation (Fig. 1). Head very wide, forming with basal part of rostrum joint cone rather strongly narrowed towards base of pterygia; entire dorsal half covered with small sparse punctures; eyes moderately large, 1.5× narrower than frons, impressed into head, moderately convex, but not projecting from head dorsal outline; frons fovea well developed, situated at frontal midlength, separating vertex/frons from anterior portion of frons dorsally fused with rostrum; hind dorsobasal portion of rostrum distinctly convex, thus well delimited from vertex/frons. Rostrum very short, 1.25× wider than long; pterygia large, strongly projecting outwards; scrobes closed anteriorly; dorsum strongly widened anteriad; epistome subtriangular, hollowed, delimited by well-developed keels, anterior margin deeply excised; area between epistomal apex and frons fovea with well-developed median keel, better developed anteriorly.

Antennae moderately robust; scape straight, weakly gradually widened apically, covered with dense, arcuate and weakly raised hair-like scales; first two funicular segments subequally long, slightly more than 2× longer than wide, weakly widened apicad; third segment isodiametric; segments 4-7 moderately transverse; segments 3-7 with 1-2 combs of semi-erect light brown arcuate setae; club 2.5× longer than wide, as long as three funicular segments combined, rather weakly widened basally, apically narrowly pointed.

Prothorax slightly transverse, 1.1× wider than long, strongly rounded at sides, widest just behind middle, covered with small dense rather weakly convex tubercles; impunctate midline not developed; anterior margin distinctly shorter than base.

Elytra 1.4× longer than wide, 1.25× wider than prothorax, basally very weakly rounded, apical portion narrowly rounded; in lateral view very weakly convex, base slightly convex, apical declivity bent under; striae composed of big, moderately deep punctures; distance between strial punctures longer than their diameter; each puncture with single recumbent hair-like scale; punctures strongly gradually reduced posteriad, making interstriae narrower than striae basally, and strikingly wider than striae apically; interstriae flat or hardly convex, covered with moderately dense microtubercles and/or rasp-punctures, shining; striae reduced posteriorly to very thin shallow sulci devoid of clear punctures; vestiture dense, largely obscuring integument.

Legs moderately short and rather thin; all femora unarmed, subequally thick; dorsal margin of fore tibia straight, only apical portion weakly curved inwards; ventral margin moderately bisinuate, with long yellow-brown long semi-erect setae; mucro well developed; apical comb consisting of long yellow-brown dense setae; tarsi rather small, second segment somewhat transverse, third segment much wider than second; onychium long, its projecting portion almost as long as preceding segment; middle and hind tarsi slightly longer than fore tarsi, in particular projecting part of onychium slightly longer than length of third segment.

Figs 1-7.

Otiorhynchus (Choilisanus) theophrastus sp. nov. (1) Habitus of holotype (male). (2) Habitus of female. (3-7) Genital organs. (3). Aedeagus ventral view. (4) Aedeagus lateral view. (5) Spiculum ventrale. (6) Sclerites of the internal sac. (7) Spermatheca.

Figs 8-9.

Habitus of Otiorhynchus (Choilisanus) magnicollis Stierlin, 1888 from Samos Island. (8) Male. (9) Female.

Ventral side of body covered with similar recumbent vestiture as elytra; first ventrite broadly, shallowly impressed; anal ventrite 1.7× wider than long, strongly convex basally, towards apex gradually flattened.

Aedeagus rather weakly gradually tapered apically, apical portion abruptly narrowed forming thin rounded apex, in lateral view weakly uniformly arched; apodemes about as long as median lobe (Figs 3-4). Projecting portion of internal sac with two unequal sclerites: a big one, feathered and elongated-pointed, and a small one, thorn-shaped (Fig. 6).

Females: (Fig. 2) body length 5.5-7.5 mm; elytra longer, 1.55× longer than wide, wider in comparison with prothorax (1.35×), less convex longitudinally; tibiae slightly more robust; first ventrite not impressed; spiculum ventrale long and slender, plate rhomboidal with apical margin moderately deeply excised (Fig. 5); spermatheca C-shaped, with very short ramus and strongly bowed and short nodulus (Fig. 7).

Figs 10-11.

Habitat aspects of Otiorhynchus (Choilisanus) theophrastus sp. nov. on Lesbos Island. (10) Oros Olympos, type locality. (11) Oros Lepetymnos.

Distribution: O. theophrastus is known so far exclusively from Lesbos Island, and probably endemic there.

Bionomy: The new species was found in April-May by the second author and Carlo Braunert from sifted leaf litter under Quercus coccifera, Platanus, cushion plants and mosses above 800 m a.s.l. in the area of the two highest peaks on the island (Figs 10-11).

Etymology: Named after the student and successor of Aristoteles, Theophrastus (371-287 BC), philosopher and naturalist native to Eresos on Lesbos Island.

Type locality: Greece, Lesbos Island, Oros Olympos, 39.07056°N 26.35417°E, 900 m.

Diagnosis: Otiorhynchus (Choilisanus) theophrastus sp. nov. is close to O. (Choilisanus) magnicollis Stierlin, 1888. Otiorhynchus magnicollis was originally described from specimens from Icaria (= Nikaria) (Stierlin, 1888), and was compared with O. grandicollis Boheman, 1842, which shows a certain similarity regarding the prothorax, although more rounded in the latter species. Much more widespread than O. magnicollis, O. grandicollis is reported from Bulgaria, Turkey up to Iran (Magnano & Alonso-Zarazaga, 2013). However, conspecifity of specimens from Turkey (Nif Dağı, Kemalpaşa; Keskin & Çevik, 2008) should be critically reinvestigated. Thanks to the comparison of specimens of O. magnicollis from Samos (used here for comparison with O. theophrastus sp. nov.) with the type in the collection of Gustav Stierlin, conserved in the SDEI, the conspecificity could be confirmed by the first author, hence the identifications in Germann et al. (2015a) are now confirmed.

O. theophrastus sp. nov. differs from O. magnicollis in: rostrum dorsum narrower, distinctly widened anteriad; pterygia larger, stronger projecting outwards, 1.6× broader than rostrum minimum width; head dorsum entirely covered with small sparse punctures; strikingly thinner antennae, third funicular segment almost isodiametric, remaining segments weakly transverse; antennal club much more elongate, gently widened basally; pronotum covered with very small dense, weakly convex tubercles; elytra more narrowly rounded at humeri; pronotal and elytral vestiture precisely recumbent; legs slim (Figs 1-2).

The rostrum dorsum of O. magnicollis is wider, subparallel sided; pterygia small, less projecting, 1.4× broader than rostrum minimum width; head dorsum covered with coarse longitudinal wrinkles; antennae very robust, funicular segments 3-7 strongly transverse; club short, very broadly rounded basally; pronotal tubercles strikingly bigger, strongly convex; elytra broadly rounded at humeri; pronotal and elytral vestiture clearly raised; legs robust (Figs 8-9).

Another similar species, O. formaneki Reitter, 1913 differs mainly from theophrastus sp. nov. in the shorter elytra (1.3× longer than wide in female) more strongly rounded basally and slightly wider in comparison with prothorax (1.4×); the elytral vestiture recumbent with rows of semi-erect setae; the pterygia smaller, less projecting and 1.4× wider than rostrum minimum width; rostrum dorsum weakly widened anteriad; antennae and legs.