Brachysomus lituratus ( Reitter, 1884 ) Yunakov, 2022

Yunakov, Nikolai, 2022, A review of the genus Brachysomus Schoenherr (Coleoptera: Curculionidae: Entiminae), Zootaxa 5193 (1), pp. 1-165 : 22

Brachysomus echinatus group

The discrimination of the B. subnudus group and B. hispidus group was based on characters of the vestiture. The species with very sparse vestiture were placed into the B. subnudus group, while the species with dense vestiture were assigned to the B. hispidus group ( Košťál 1991a,b). However, vestiture basically reflects ecological adaptation (such as humidity of substrate and or level of solar radiation) rather then phylogenetic relationship. Structure of rostrum and genitalia is quite uniform among these species. Therefore the B. echinatus group is established here to unite the species related to B. echinatus with the B. subnudus group and B. hispidus group.

Description. Body length 1.8–2.95 mm. Body densely or sparsely covered with round, ovate, or lanceolate scales, not excised at apex. Elytral interstriae with rows of light, erect, apically obtuse scales. Mandibles in male without thorn-like pedicel. Eyes slightly or (rarely) moderately convex, but not hemispherical. Antennal scape evenly widened to apex. Epifrons sometimes separated from vertex by slight transverse depression; at base equal or slightly wider than at the level of antennal insertion. Rostrum laterally without prominences anterior to eyes. Body densely or sparsely covered with round, oval, or piliform scales. Erect setae longer or shorter than width of elytral interstriae (about 0.4x as long as interstrial width). Epistome separated from epifrons by distinct, thin V-shaped ridge.

Composition. This species group contains 14 species related to B. echinatus , B. subnudus , and B. hispidus . Brachysomus lituratus ( Reitter, 1884) , comb. n. is transferred from the genus Foucartia Jacquelin du Val, 1854 because its head is almost identical to that of B. hispidus , B. frivaldszkyi and related species, and similarity of its male genitalia to that of B. frivaldszkyi ( Figs. 185 , 190 ).

Figures

FIGURE 185. Brachysomus kratkyi: A: aedeagus, dorsal and lateral view; B: tegmen; C: tergite VIII with alical process (frontal wiew); D: spermatheca. Brachysomus lituratus (Reitter, 1884) comb. n.: E: aedeagus, dorsal and lateral view; F: tegmen; G: tergite VIII; H: spermatheca; I: scales of elytra.

FIGURE 190. Brachysomus frivaldszkyi: A: body; B: aedeagus, dorsal and lateral view; C: tegmen; D: spermatheca; E: tergite VIII.