Giavarhynchus Bellò, Osella & Ruzzier, 2021

Bello’, Cesare, Colonnelli, Enzo, Forbicioni, Leonardo, Osella, Giuseppe & Ruzzier, Enrico, 2021, A new genus and species of anophthalmous Otiorhynchini from Greece, with a new synonymy and new combinations (Coleoptera: Curculionidae, Entiminae), Zootaxa 4938 (1), pp. 69-84 : 71-75

Giavarhynchus Bellò, Osella & Ruzzier gen. n.

( Figs 1 a-1n)

Type species. Giavarhynchus amicorum Bellò, Osella & Ruzzier sp. n.

Diagnosis. Blind, large-sized (7.3-8.0 mm) Otiorhynchini easily distinguishable from all other genera by the following combination of characters: elongate rostrum with a ventral transverse furrow and excised lateral margins located at apical third ( Figs 1 d-1e), punctation of pronotum of two distinct sizes arranged in a distinctive pattern (figs. 1a, 1b, 2a, 2c, 2f), interval 7 of elytra crenulate in basal eighth (figs 1a, 1g, 2a); by metafemora bearing a spine-like tooth placed at apex of distal third and much larger than that of pro- and mesofemora ( Fig. 1a , 2a ); tibiae of female granulate on inner margin, granules particularly strong on the bisinuous mesotibiae (figs 1a, 1c, 1f); and tarsi thin and elongate, segment 3 only slightly wider than the preceding two (figs 1a, 1c).

Description. Body elongate (TL: 7.30–8.00 mm; BL: 5.60–6.60 mm), colour brownish-black, dull or weakly glossy, antennae and legs paler.

Head globular and smooth. Rostrum elongate (RL: 1.30–1.60 mm, RW: 0.50–0.60 mm, RL/RW: 2.60–2.67), regularly curved from base to apex. Scrobes deep, completely visible in dorsal view. Pterygia evident. Rostrum ventrally in apical third with deep transverse furrow. Apex of rostrum with sparse raised short setae. Upper surface of mesorostrum with setae on both sides, carinae sub-parallel to the lateral margin. Epistome absent. Genae elongate, scarcely punctured. Mandibles in horizontal plane, with scar indicating point of attachment of deciduous cusps; mandibular scars present. Eyes absent. Forehead (FW / MW: ratio 1.50–1.60) in lateral view slightly convex, intraocular pit not visible. Submentum without pappolepida.

Antennae long and thin (SL: 1.30–1.40 mm, FL: 2.00– 2.10 mm, SL/FL: 0.65–0.67). Scape about 4-5 times as long as wide, straight, with widened and curved apex. Funicle with 7 antennomeres, all with fine setae. Relative length of antennomeres 1-7 of funicle, in millimetres: 0.32–0.34, 0.30–0.32, 0.18–0.20, 0.18–0.20, 0.12–0.15, 0.16–0.18, 0.16–0.18; length of antennal club: 0.58–0.60. Club fusiform, as long as the last four funicular antennomeres, almost 3 times as wide as the funicle, basal antennomere of club elongate and glabrous, the remaining two with golden pubescence and some thin, long setae.

Pronotum longer than wide (PL: 1.80–1.90 mm, PW: 1.70–1.80 mm, PL/PW: 1.05–1.06) with strongly rounded margins, widest at middle, anterior and posterior margins straight, the anterior one much narrower than the posterior margin. Disc with irregularly placed large and fine punctures bearing long erect setae; punctures more distant from each other than on sides; interspaces between punctures often shiny and microreticulate.

Elytra dorsally almost glabrous, slightly shining, in dorsal view oval-elongate, in lateral view slightly vaulted (EL: 4.40–4.80 mm, EW: 2.60–2.80 mm, EL/EW: 1.70–1.72). Elytra slightly convex, widest at middle of moderately rounded sides, not fused but suture ill defined. Humeri protruding, angular and toothed ( Fig. 1g ). Wings absent. Each elytron with nine complete striae; seventh stria raised and prominent particularly at humeri. Interstriae convex, with 10 to 20 punctures and with sparse thin setae. Elytral declivity from 60 to 75 degrees.

Legs long, slender, with long setae, and more or less large tooth on each femur. All femora clubbed at middle, tooth of metafemur very large and with four to five small tooth-like tubercles. All tibiae mucronate, with fringe of thick golden setae on inner apical angle, protibia with distinct inner apical grooming brush, tarsomere 1 elongate, conical, 2 short and transverse, 3 deeply bilobed; all tarsomeres with thin golden setae. Onychium curved, thin and elongate.All coxae globular, procoxae almost connate, mesocoxae separated by a space almost equal to the diameter of a mesocoxa, metacoxae separated by a space about three times their diameter.

Abdomen shiny, slightly rugose, finely punctured; each puncture bearing a short seta.

Male terminalia. Unknown.

Female terminalia. Female genitalia as in figs: (1i) spermatheca; (1l) VIII sternite; (1m) III- VII sternites; (1n) gonocoxites. Gonocoxite small, rather slender, weakly sclerotized, evenly tapered apicad, stylus elongate, with tuft of 4–6 setae at apex. Sternite VIII with long, straight and slender apodeme terminating just at base of plate, creating a short basal margin. Plate of sternite VIII trapezoid and with longitudinally developed arms, apical margin welldefined, armed with fringe of setae. Spermatheca sclerotized, small, slender, cornu slender, corpus small, ramus slightly longer than wide, nodulus smaller, hump-shaped.

Etymology. The new genus is named after our friends and colleagues Pier Mauro Giachino and Dante Vailati (World Biodiversity Association, Verona, Italy), collectors of the type material. The name is a combination of their surnames initial Gia[chino]Va[ilati] and [Otio]rhynchus, a supposedly closely related weevil genus, resulting thus in Giavarhynchus . Gender masculine.

Remarks. The lack of or extreme reduction of eyes is not such an uncommon feature among the soil-dwelling Entiminae . Morrone & Hlaváč (2017) listed all world taxa of such entimines presently known, which occur in seven tribes: Celeuthetini Lacordaire, 1863 (genera Genavius Osella, 1983 from New Caledonia and Guineobius Osella, 1983 from New Guinea), Laparocerini Lacordaire, 1863 (some species of Laparocerus Schoenherr, 1834 from the Canary Islands and Madeira), Pachyrhynchini Schoenherr, 1826 (genus Schauenbergia Osella, 1977 from Réunion), Peritelini Lacordaire, 1863 (genera Hobarypeithes Hustache, 1939 and some species of Dysommatus Marshall, 1933 , both from Africa, plus Solariola Flach, 1908 , and Troglorhythmus Alziar & Lemaire, 2008 both from Europe); Sciaphilini Sharp, 1891 (genus Abarypeithes Hustache, 1939 from Africa), Typhlorhinini Kuschel, 1954 (genera Cambefortinus Richard, 1986 , Cephalorostris Richard, 1979 , Hopactorrhynchus Richard, 1953 and Scrobops Richard, 1979 from Madagascar and West Africa), and Otiorhynchini (five taxa from the Palaearctic). Among these last, although one or another of the features of Giavarhynchus , including lack of eyes, can be found in some Mediterranean otiorhynchines, the presence of all of the characters detailed in the diagnosis is unique to the genus described here. Firstly, the unusual deep rostral constriction is shared with both the Moroccan species Otiorhynchus deceptorius Białooki, Germann & Pelletier, 2017 and Otiorhynchus incisirostris Białooki, Germann & Pelletier, 2017 which were incidentally wrongly placed ( Białooki et al. 2015) in the subgenus Lixorrhynchus Reitter, 1914 rather than in Aranihus Reitter, 1912 to which they evidently belong because (new subgeneric placement). Secondly, the ventral rostral furrow is also present in the Cretan genus Mirorhynchus Magnano, 2003 . All the above cited taxa clearly have a shorter rostrum, well developed eyes and edentate (or almost so) femora and cannot be confused with Giavarhynchus . In particular, whereas both Otiorhynchus (Aranihus) deceptorius and Otiorhynchus (Aranihus) incisirostris appear also to be very different from Giavarhynchus amicorum on the basis of their very weakly granulate tibiae, lacking humeral tubercles, and granulate pronotum, Mirorhynchus bellus Magnano, 2003 from Crete (not from Cyprus as wrongly reported in the title of its description ( Magnano 2003)), has a similar or even stronger tibial denticulation compared to that of G. amicorum , but on the inner margin of the protibiae instead of on the meso- and metatibiae. It is however immediately distinguishable by the squamiform-like punctation of pronotum, lack of humeral tubercles and oval shape ( Germann et al. 2021). The loss of eyes is a morphological convergence of Giavarhynchus with Baldorhynchus Di Marco & Osella, 2002 , Ioniorhynchus Magrini, Meoli & Abbazzi, 2005 , and with some Otiorhynchus of the subgenera Aranihus Reitter 1912, Cavernodes Białooki 2015, Italorrhynchus Magrini, 2019, Lixorrhynchus Reitter, 1914 and Troglorhynchus F. Schmidt, 1854 .

Giavarhynchus is one of the nine genera or subgenera of micro-or anophthalmic subterranean weevils occurring in Greece ( Morrone & Hlaváč 2017). Two of these are apparently endemic to this country, namely Hauseriola Osella, 1980 and Giavarhynchus , whereas the remaining six are not, namely Absoloniella Formánek, 1913 , Amaurorhinus Fairmaire, 1860 , Ioniorhynchus Magrini, Meoli & Abbazzi, 2005 , Otiorhynchus Germar, 1822 , Styphloderes Wollaston, 1873 and Ubychia Rost, 1893 . Giavarhynchus is surely one of the most peculiar entimine genera due to its unique morphology, also being somewhat similar, although distantly related, to Solariola Flach, 1908 and Troglorhythmus Alziar & Lemaire, 2008 , genera which include much smaller species and which are both presently placed in Peritelini ( Bellò et al. 2019).

The presence of a marked cuticular sculpture, tuberculate elytral humeri and strongly punctured elytral striae suggest a perhaps recent adaptation of Giavarhynchus to life in the superficial subterranean habitat. As in most endogean Otiorhynchini both elytra and elytral humeri are smooth.

Figures

FIGURES 1a–1c. Giavarhynchus gen. n., habitus: 1a—dorsal view of the female holotype; 1b—ventral view of the female paratype; 1c—lateral view of the holotype. Scale bar: 1 mm. TL of the holotype: 8.00 mm; TL of the paratype: 7.30 mm. Photograph courtesy of Francesco Sacco.

FIGURE 2a. Giavarhynchus amicorum sp. n. female holotype, habitus in dorsal view. Scale bar: 1 mm. Photograph courtesy of Francesco Sacco.