Brachysomus (Hippomias) argutus Yunakov, 2006

Yunakov, Nikolai, 2022, A review of the genus Brachysomus Schoenherr (Coleoptera: Curculionidae: Entiminae), Zootaxa 5193 (1), pp. 1-165 : 65-66

Brachysomus (Hippomias) argutus Yunakov, 2006

Figs. 131 , 221 , 239B

Brachysomus argutus Yunakov, 2006: 308 . Type locality: Romania, Zvonce.

Redescription. Measurements: Body length 1.60–2.50 mm, width 0.90–1.45 mm; in holotype 1.60 and 0.90 mm.

Vestiture: Body with silky pubescence, thinly covered with piliform scales and suberect setae; setae evenly widened apically, uniformly distributed along entire surface of elytra, as long as 0.5 of interstrial width. Ventrites covered with hairs and piliform scales. Colouration: Body, legs and antennae brown.

Head: Male. Rostrum noticeably conically narrowing from base to middle, almost as long as wide (RL/RW = 1.05). Pterygia clearly visible in dorsal view, strongly projecting from outline of rostrum. Epifrons parallelsided, weakly convex longitudinally, separated from vertex by transversal depression, with noticeable thin median longitudinal sulcus. Eyes small (VW/ELD = 2.0), oval, strongly convex, situated lower of level of vertex.. Vertex weakly convex. Antennae: scape weakly curved, evenly widened distally; funicular antennomeres: 1st and 2nd elongate, 3rd as long as wide; 4 th –7th transverse; club broad, spindle-shaped, weakly separated from the funicle.

Thorax: Pronotum weakly transverse (PL/PW = 0.82), widest at middle, weakly convex at sides and disc, weakly constricted anteriorly and posteriorly. Sculpture under scales reticulate, included finely, densely, and shallowly punctures at disc, fluently transforming into micro-granules at sides. Elytra: nearly cordate, (EL/EW = 1.25), strongly and irregularly convex at sides, widest anteriad of mid length. Disc moderately convex, longitudinally and in cross-section. Striae linear. Punctures deep, slightly separated; spaces between punctures somewhat narrower than diameter of puncture, situated deeper than interstrial level. Interstriae flat, shiny, 2x wider than striae. Legs: Femora moderately swollen in middle part. Protibiae straight from outside, external apical angle weakly projecting from contour of protibiae, interior side S-shaped. Metatibiae not sinuate interiorly, with small mucro and bunch of long pale hairs near apex. First tarsomere triangular, 2nd strongly transverse. Fifth fore tarsomere extending beyond apical lobes of 3rd by 0.65 length of the lobes.

Abdomen: Fifth ventrite weakly convex, with slight depression at apical part, apical margin slightly sinuate. Male genitalia: Median lobe slightly sclerotized, 1.5x shorter than apodemes, distinctly widened in basal half; endophallus with sparse spiculate field, spiculae thin and acute. Spermatheca with very narrow cornu.

Diagnosis. Brachysomus argutus is similar to B. rhinomioides in the structure of the head, but closely related and similar to B. carpathicus . From B. rhinomioides it differs by gently convex epifrons, slight transverse depression at base of epifrons, thin pubescence on elytral interstriae, shorter suberect setae; shape of pronotum, weakly convex disc of elytra, distinct pubescence on interior side of metatibiae, 5th ventrite weakly convex and depressed in apical part, and structure of aedeagus. From B. carpathicus it differs by the elongate rostrum, depressed base of epifrons, distinct pubescence on interior side of metatibiae and structure of aedeagus.

Distribution. SE Serbia.

Bionomics. Unknown.

Type material. Holotype, ♂ (BRc) Serbia: ‘SE Serbia, Zvonce env., nr Pirot, 27.iv.2002, T. Lackner’.

Additional material examined. SERBIA: 12♂7♀ (KJc) Pirot, Brakita env., 2.v.2002, T. Lackner leg.

Figures

FIGURE 221. Brachysomus argutusus: A: aedeagus; B: tegmen; C: spermatheca; D: head; E: antenna; F: pronotum, lateral view; G: hind tibia of male.

FIGURE 239. Occurrence map of Brachysomus: A: Brachysomus s. str.; B: subgenus Hippomias.

FIGURES 130–135. Brachysomus, main view. 130: B. alexeevi. 131: B. argutus 132: B. armatus 133: B. boroveci 134: B. pelex. 135: Eurosphalmus tenuicollis comb. n.