Eudraces barclayi, Borovec & Nakládal, 2018

Borovec, Roman & Nakládal, Oto, 2018, Eudraces barclayi sp. nov., with some notes on the genus Eudraces Marshall (Coleoptera: Curculionidae: Entiminae: Myorhinini), Zootaxa 4392 (2), pp. 374-382 : 375-378

EudraceS barclayi spec. n.

( Figs 1, 2–9 )

Type material. Holotype: ♂, ‘ SOUTH AFRICA, Transvaal [Gauteng], N. Pretoria Dist. , 29.I.1928, Prof. J. C. Faure [lgt.]’ ( BMNH) . Paratypes: 12 ♂♂ ♀♀, the same data as holotype ( BMNH) ; 1 ♂ 2 ♀♀, ‘[ South Africa, North West] Vryburg ( Bech. 1.), 1893, E. Simon [lgt.]’ ( BMNH) ; 1 ♀, ‘[ South Africa, Gauteng], Pretoria, Tvl. (Pta.- Noord), Jan. [ January ] 1961, H. v. Schalkwyk [lgt.]’ ( SANC) ; 1 ♂, ‘[ South Africa, Northern Cape], Kimberley , KP., 29-1-1971, H. van Schalkwyk en A. Pienaar [lgt.]’ ( SANC) ; 1 ♂, ‘ S. Africa, O.F.S. [ South Africa, Free State], Wesselsdam 379, Boshof, SE 2825 Ba, 15–16 Feb. [ February ] 1978, A. Strydom [lgt.]’ ( NMBH).

Description. Body length 2.28–2.74 mm, holotype 2.38 mm. Vestiture. Body ( Fig. 1) reddish brown, antennae and legs slightly paler, yellowish red, elytra in several specimens darker, brownish. Elytra densely covered by regularly rounded appressed scales, unicoloured bright green with weak goldish sheen, 4–5 across one interval width. Pronotum and head with rostrum densely covered by rounded appressed scales, distinctly smaller than elytral ones, hiden integument, greenish or disc of pronotum and anterior half of rostrum pinkish beige or greyish with metallic sheen. Body ventrally sparsely covered by drop-shaped appressed scales with weak greenish sheen. Scapes and funicles with semiappressed, sparse, greyish slender subspatulate setae, clubs finely and densely setose with several sparse, longer erect fine setae. Femora with long oval appressed greyish scales, tibiae with semiappressed subspatulate greyish setae, tarsi with semiappressed piliform setae.

Rostrum ( Figs 2, 3 ) in comparison with other Myorhinini moderately short and robust, 1.27–1.36× as long as at base wide, widest at base and here 1.43–1.54× as wide as at apex, in posterior half tapered apicad, with distinctly concave sides, in anterior half parallel-sided, only around antennal scrobes slightly enlarged, dorsally densely squamose, only in short apical part somewhat scales sparser. Rostrum in lateral view curved, enlarged in anterior half around antennal scrobes, significantly separated from head by deep saddle-shaped indentation, laterally and ventrally glabrous. Epifrons narrowest at midlength of rostrum and here slightly wider than clubs, anteriad enlarged with convex sides, in anterior half 0.6× as wide as rostrum in the same place, evanescent posteriad. Antennal scrobes dorsally in the form of two deep long oval fossae carinated anteriad and evanescent posteriad, placed about at anterior third of rostrum. Scrobes laterally very dorsally placed, narrow, furrow-shaped, with distinct ventral edge which is siginificantly curved, dorsal border copies dorsal border of rostrum, not well edged, scrobes anteriad and posteriad evanescent. Head very short and wide, laterally distinctly vaulted. Eyes laterally placed, space between them wide almost as base of rostrum and 1.1–1.2× as wide as rostrum at apex; moderatelly small, vaulted, weakly prominent from outline of head; laterally oval, not reaching dorsal border of head, placed in dorsal half of head.

Antennae long and slender. Scapes somewhat exceeding posterior border of eyes when folded posteriad, 1.2× as long as funicle, about straight, only at apical fifth mallet-shaped enlarged, slightly narrower than clubs. Funicle 7-segmented; segments 1 and 2 slender and long, conical, segment 1 2.1–2.3× as long as wide and 1.5–1.7× as long as segment 2, which is 1.8–1.9× as long as wide; segments 3–7 1.3–1.4× as long as wide; clubs slender, 2.7–3.1× as long as wide, at base weakly constricted.

Pronotum ( Fig. 1) wide, 1.68–1.76× as wide as long, widest at basal third with distinctly rounded sides, anteriad significantly more tapered than posteriad, behind anterior border weakly constricted; base weakly arched; disc regularly vaulted; anterior borders laterally weakly concave. Scutellum invisible.

Elytra ( Fig. 1) short oval, 1.16–1.21× as long as wide, widest at midlength, with distinctly rounded sides, apically rounded; laterally distinctly vaulted. Striae narrow, line-shaped; intervals flat, wide.

Abdominal ventrite at middle 1.5×, behind metacoxa as long as ventrite 2; ventrite 2 equally long as ventrites 3 and 4 combined; ventrite 5 in males short, broadly rounded. Suture 1 fine and sinuose, the others wide and deep. Ventrites glabrous and finely punctate. Metaventral process obtuse and narrow, half as wide as transverse diameter of metacoxa.

Femora adentate. Protibiae 6.0–6.6× as long as wide at midlength, equal in both sexes; protibiae distinctly scooped at inner edge in anterior half with 5–6 brownish small spines, apes rounded with fringe of brownish setae, mucronate. Metatibiae ( Fig. 4 ) denticulate as protibiae; apical surface glabrous; corbels not developed. Tarsal segment 1 1.7–1.9× as long as wide, distinctly narrower than segment 3; segment 2 1.2–1.3× as long as wide; segment 3 1.3–1.4× as wide as long and 1.7–1.9× as wide as segment 2; onychium 0.9× as long as segment 3; claws free, separated, brownish.

Male terminalia. Penis ( Fig. 5 ) weakly sclerotised, moderately short, widest at base, distinctly evenly tapered apicad, apex narrow, regularly tapared; laterally irregularly curved, at apical quarter curved inside, tapered. Temones equally long as body of penis. Tegmen ( Fig. 6 ) with slender ring and long parameres, their base distant, manubrium short, slightly shorter than parameres. Sternite IX anteriorly tapered and curved.

Female terminalia. Sternite VIII ( Fig. 7 ) with small narrow plate, subtriangular, with well visible apical and basal margin, with apodeme terminated inside and tuft of fine setae at apex. Gonocoxites ( Fig. 8 ) of ovipositor slender, evenly tapered apicad, with moderately long apical styli. Spermatheca ( Fig. 9 ) with weakly curved, somewhat short cornu; rounded corpus; ramus straight, longer than wide, nodulus equally long but more slender, obliquely placed to ramus, tapered apicad with tip curved inside.

Derivation of name. The newly described species is dedicated to Maxwell Barclay (BMNH) who was able to discover material of this species in the collection of the Natural History Museum and who helped the senior author many times by providing him with material important for his studies.

Differential diagnosis. This species is unusual among all known Eudraces species, and is very easily separated from all others based on the following set of unique characters: body small, less than 3 mm (at least 3.3 mm in all other Eudraces species), elytra in both sexes wide, short oval (slender to very slender in males, elliptical to ovate in females of all other Eudraces species) and rostrum robust and short, laterally slightly longer than pronotum, distinctly wider than profemora at middle (slender and long, distinctly longer than pronotum, as wide as profemora at middle in all other Eudraces species).

Using the characters noted above to distinguish and define genera in Myorhinini , as used already by Marshall (1908) and Oberprieler (1995), E. barclayi sp. n. belongs to Eudraces . On the other hand it is different from all other species of the genus not only by a shorter and more robust rostrum (mainly in dorsal view) but also by the female sternite VIII, which has small slender subtriangular plate with well distinguished basal border, an exceptional form in all Myorhinini genera and almost identical with that of Ellimenistes Boheman, 1843 ( Embrithini Marshall, 1942 ). All other Eudraces species have sternite VIII with the plate moderately large, umbrella-shaped, with an ill-defined basal margin. Marshall had already attached a label ‘ Eudraces ? sp.n. ’ to one of the paratype specimens of E. barclayi sp. nov., and I cannot justify erection of a new genus for this unusual Eudraces species, based only on the female genitalia and the short, more robust rostrum.

Figures

FIGURES 2–17. Structural details of Eudraces Marshall. 2–9. E. barclayi sp. n. 2. head with rostrum, dorsal view; 3. head with rostrum, lateral view; 4. right metatibia; 5. penis, ventral and lateral view; 6. tegmen, dorsal view; 7. sternite VIII of female, dorsal view; 8. ovipositor, dorsal view; 9. spermatheca. 10–13. right metatibia. 10. E. fallaciosus (Voss); 11. E. faurei Marshall; 12. E. flavirostris Marshall; 13. E. munroi Marshall. 14–17. penis, ventral and lateral view. 14. E. fallaciosus (Voss); 15. E. faurei Marshall; 16. E. flavirostris Marshall; 17. E. munroi Marshall.