Brachysomus (Brachysomus) rokosensis Benedikt, 2001

Yunakov, Nikolai, 2022, A review of the genus Brachysomus Schoenherr (Coleoptera: Curculionidae: Entiminae), Zootaxa 5193 (1), pp. 1-165 : 32-33

Brachysomus (Brachysomus) rokosensis Benedikt, 2001

Fig. 79, 80 , 145 , 188A–D , 238A

Brachysomus rokosensis Benedikt, 2001: 140 . Type locality: Dolné Vestenice env. (Slovakia).

Redescription. For detailed description see Benedikt (2001). In addition: Legs: Middle tibiae in holotype straight externally, weakly sinuate internally; hind tibiae almost as in B. subnudus : internally weakly sinuate at apical third, with small but clearly visible mucro. Second tarsomere weakly transverse, 3rd broad with large lobes, 5th fore tarsomere extending beyond apical lobes of 3rd by length of the lobes. Abdomen: First ventrite with posterior margin weakly sinuate. Male 5th ventrite flat, with deeply sinuate posterior margin, which bears bunches of setae on both sides of sinuation. Male genitalia: Aedeagus heavily sclerotized; median lobe 0.75 x as long as apodemes; parameres free from base, as long as tegminal apodeme. Spermatheca: collum distinctly larger than ramus.

Diagnosis. Brachysomus rokosensis is very similar to B. dispar and B. subnudus . From both species it differs only in the following male characters: setae almost recumbent, their length equaling 1/3 width of interstriae (in B. dispar and B. subnudus length of setae equals 1/2 and 2/3 width of interstriae respectively), erect setae and recumbent scales have the same shape and width (in B. dispar scales lanceolate, or oblong-oval, setae spatulate, widened apically, setae as wide as scales; in B. subnudus scales distinctly slender than setae); male 5th ventrite strongly depressed, sinuate at apex. In B. rokosensis the apex of the median lobe is evenly narrowed, endophallus has a single field of uniform tiny spicules ( Fig. 188A ); in B. subnudus the apex is attenuate, endophallus has two fields of diferent larger and smaller spicules Fig. 186A ,

Distribution. Czechia, Slovakia.

Bionomics. This species inhabits leaf- or grass-litter in xerothermic bush lands and forests with Quercus pubescens on limestone from 250 to 450 m a.s.l. ( Benedikt 2001).

Remarks. The original description of Brachysomus rokosensis has been carefully prepared by Benedikt (2001). The characters of the legs in male that are often useful for identification of Brachysomus species are added here to the original description.

Type material. Holotype (♂) (NMPC): ‘Slovakia occ., 29.5.1998, Dolné Vestenice env., forest-steppe, 7276, S. Benedikt leg.’; Paratype (♀) (NMPC) data as in holotype.

Figures

FIGURE 186. Brachysomus subnudus: A: aedeagus, dorsal and lateral view; B: tegmen; C: spermatheca; D: scales of elytra; E: sternite VII; F: tergite VIII.

FIGURE 188. Brachysomus rokosensis: A: aedeagus, dorsal and lateral view; B: tegmen; C: spermatheca; D: sternite VII. Brachysomus bohemicus: E: aedeagus, dorsal and lateral view; F: spermatheca.

FIGURE 238. Occurrence map of Brachysomus s. str.

FIGURES 79–86. Brachysomus, details: 79, 80: B. rokosensis. 81, 82: B. slovacicus. 83, 84: B. hispidus. 85, 86: B. lituratus.

FIGURES 142–147. Brachysomus, dorsal habitus: 142: B. subnudus, male. 143: idem, female. 144: B. slovacicus, male 145: B. rokosensis, male. 146: B. hispidus, male. 147: B. hispidus, female.