Parvorhynchus, 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 : 339-340

Parvorhynchus gen. nov.

Type species. Parvorhynchus sordidus sp. nov., by present designation.

Description. Size less than 3.0 mm. Head, prothorax and elytra densely clothed by earthy crust and by specialized long, erect, clavate scales arranged as follows: four on head, row of 3–4 scales along edge limiting epifrons, few scattered scales on pronotal disc, row on each elytral interval. Legs and antennae with stiff, erect, partly slightly clubbed setae. Rostrum relatively elongate, slightly widening from base to antennal insertion, then narrowing towards apex. Scrobes entirely visible in dorsal view, in lateral view appearing as bare shiny subtrapezoidal area. Epifrons with sides subparallel and angularly sloping, its dorsum feebly convex and not keeled, its level slightly higher than that of head. Epistome widely subtriangular, smooth, bare on disc and setose on sides, not completely hiding mandibles, and with broad incision at apex. Mentum bisetose. Mandibles quadrisetose. Head elongate, slightly conical, eyeless, dorsum flattened, interocular space with rather deep longitudinal sulcus visible only when crust is removed. Pronotum with dense punctures hidden by crust, anterior margin truncate, posterior one slightly convex, sides moderately rounded, disc flat with feeble anterior depression, its uneven surface visible only when crust is removed. Scutellum invisible. Elytra elliptically elongate, 10-striate, concave at base, disc flat, apical declivity rather abrupt. Legs quite elongate, femora moderately clubbed, edentate, tibiae curved inwards beyond apical third, internal margin somewhat mucronate apically, metatibiae with open corbels, claws free.

Ventral side. Procoxae contiguous and situated at middle of prosternum, mesocoxae narrowly separated by a triangular projection of mesoventrite, metaventrite slightly longer than mesocoxae, metacoxae separated by distance greater that their diameter, abdominal ventrite I with broad shallow depression in middle and longer than combined length of following three ventrites which are subequal in length, ventrite V crescent-shaped, slightly convex and hardly as long as combined length of ventrites III+IV.

Differential diagnosis. The taxonomy of the African entimine tribes is currently all but clear ( BOROVEC et al. 2009). With regard to those including genera with blind species, KUSCHEL (1954) proposed the tribe Typhlorhinini for some African and Madagascan genera with free claws, a tribe which appears poorly defined, the apparent lack of deciduous mandibular cusp being the only reliable character upon which they can be differentiated from the close Otiorhynchini Schoenherr, 1826 . Parvorhynchus gen. nov. undoubtedly belongs to the Otiorhynchini as presently understood on account of its free claws, pit-like dorsal scrobes and quadrisetose mandibles. The single small blind member of the new genus is somewhat similar only to the Caucasian species of Otiorhynchus Germar, 1822 , subgenus Troglonamertanus Davidyan & Savitsky, 2006 , some of which are also eyeless ( DAVIDYAN & SAVITSKY 2006), although the Parvorhynchus gen. nov. differs immediately by its dense earthy coating completely hiding the cuticle, erect clavate setae on head, rostrum and elytra, epifrons not keeled in the middle and with its sides angular instead of rounded, pronotum not very strongly punctured, base of elytra not S-shaped, intervals not granulate, presence of erect soft setae on internal margin of the male metatibiae. Also some small species of Otiorhynchus subgenus Namertanus Reitter, 1912 lacking femoral teeth are rather similar to the new genus, but they also differ, in addition to the presence of eyes and the much shorter rostrum and pronotum, by the same characters mentioned above, except S-shaped base of elytra ( Figs 47 , 48, 50 ). None of the other Otiorhynchini can be confused with Parvorhynchus gen. nov.

Etymology. The name of this new genus is a combination of the Latin ‘ parvus’, meaning small, and the Greek ‘ρύνχος’ meaning beak, in reference to its small size. Gender is masculine.

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.

Figs 47–52.47–49 – Parvorhynchus sordidus sp.nov., holotype:47 – habitus; 48 – habitus in side view;49 – aedeagus in dorsal view. 50 – Otiorhynchus (Namertanus) argus Reitter, 1896 from Abkhazia, habitus. 51–52 – Epactus hirticornis sp. nov.: 51 – habitus of the holotype; 52 – aedeagus of a paratype in dorsal view.