Brachysomus (Brachysomus) simplex Yunakov, 2006

Yunakov, Nikolai, 2022, A review of the genus Brachysomus Schoenherr (Coleoptera: Curculionidae: Entiminae), Zootaxa 5193 (1), pp. 1-165 : 36-37

Brachysomus (Brachysomus) simplex Yunakov, 2006

Figs. 165, 169 , 192H–K , 239A

Brachysomus sinplex Yunakov, 2006: 296 . Type locality: North Macedonia, Mt. Ljuboten

Redescription. Measurements: Body length 2.35–2.87 mm, width 1.35–1.50 mm. Vestiture: very thin; head and pronotum sparsely clothed with light piliform scales. Elytral interstriae evenly clothed with piliform scales and bearing short, fine, pointed, erect setae, their length somewhat less than interstrial width. Antennae, legs, and ventrites with fine pubescence. Antennal scape and funicle, tarsi, and inner margins of tibiae, clothed with fine hairs. Colouration: Body, antennae, and legs light brown.

Head: Rostrum as long as wide, weakly narrowing from base to middle, then parallel-sided, lateral margins in line with lateral margins of temples. Antennal sockets distinctly visible in dorsal view. Pterygia not projecting from outline of rostrum. Antennal scrobes narrowly visible in anterior half, gradually disappearing posteriad, directed to ventral margin of eye, not reaching ventral side of rostrum, smoothly merging with lateral surface of rostrum. Epistome weakly convex, without carina. Epifrons scarcely narrowed to midlength, parallel-sided from midlength to apex, flat, not carinate, with shallow or deep median longitudinal sulcus, without transverse depression. Vertex flat, finely punctate, 2x wider than epifrons at level of antennal insertion. Eyes oval (VW/ELD = 2.28–2.36), weakly convex, highest at middle. Antennae: Scape almost straight, strongly widened along distal 1/3; funicular antennomeres: 1st (L/W=1.75) and 2nd (L/W=1.66) elongate, 1st 1.40x longer than 2nd; 3rd and 4th moniliform, 5th–7th transverse; club egg-shaped.

Thorax: Pronotum transverse [PL/PW = 0.71–0.77], widest at middle, gently and evenly convex at disc and sides, constricted posteriorly. Disc finely reticulated, its sculpture consisting of dense fine polygonal punctures, with spaces between punctures somewhat narrower than diameter of a puncture; sides of pronotum finely granulate, disc without lateral depressions. Elytra: oval (EL/EW = 1.30–1.33), weakly gradually convex at sides. Disc strongly convex transversely and moderately, almost evenly convex longitudinally. Elytral interstriae weakly convex, shiny, in male 1.5x, in female 3x wider than striae. Punctures broadly separated; spaces between punctures very weakly concave, somewhat narrower than diameter of puncture. Legs: Fore tibiae straight, apical external angle not protruding. Hind tibiae in male with small mucro. Second tarsomere transverse (L/W = 0.5). Fifth fore tarsomere extending beyond apical lobes of 3rd by 0.6 length of the lobes.

Abdomen: First ventrite with posterior margin weakly sinuate. Spermatheca: ramus and collum connate at base, ramus 2x longer than collum.

Diagnosis. Brachysomus simplex is distinguished from all species of the subgenus Brachysomus s. str. by the very fine pubescence of body and shape of the head. It is very similar to B. longipterus in the form of the head, the structure of the antennal scrobes, and the type of body vestiture, but differs by the broadly-oval shape of the elytra, the shorter rostrum, the straight and weakly mucronate fore tibiae and the shorter and slightly sclerotized aedeagus. From B. deceptorius it differs in the fine, dense punctures of the pronotum, the presence of proximal and distal constrictions on the pronotum, the 1st funicular antennomere 1.4x longer than 2nd (in B. deceptorius 1st funicular antennomere 2x as long as 2nd), pterigia not projecting from outline of rostrum and collum of spermatheca protruding.

Distribution. Serbia, North Macedonia.

Bionomics. This species inhabits the subalpine zone around 1600–2000 m a.s.l.

Type material. NORTH MACEDONIA: Holotype, ♀ (HNHM), Šar Planina Mountain Range, Ljuboten [Mt.], 4–18.vii.1935 (J. Fodor).

Additional material examined. SERBIA: 1♀, Šar Planina Mountain Range, Nerod. Brezovica, Piribeg Mt., 1600 m, 14.vii.1997 P. Moravec leg. (BRc).

Figures

FIGURE 192. Brachysomus deceptorius: A: aedeagus, dorsal and lateral view; B: tegmen; C: spermatheca; D: tergite VIII; E: head; F: pronotum; G: antenna. Brachysomus simplex: H: head; I: antenna; J: pronotum; K: spermatheca.

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

FIGURES 164–172. Brachysomus, details: 164: B. deceptorius, male. 165: simplex, female. 166: B. longipterus, male. 167: idem, female. 168: B. deceptorius, male head dorsal view. 169: simplex female. 170: B. deceptorius, male head lateral view. 171: B. longipterus, male head dorsal view.