Brachysomus (Hippomias) laticollis Košťál, 1992

Yunakov, Nikolai, 2022, A review of the genus Brachysomus Schoenherr (Coleoptera: Curculionidae: Entiminae), Zootaxa 5193 (1), pp. 1-165 : 63-64

Brachysomus (Hippomias) laticollis Košťál, 1992

Figs. 46 , 116, 117 , 219 , 239B

Brachysomus laticollis Košťál, 1992: 42 . Type locality: Romania, Turnul Roşu Pass; Białooki, 2007: 164.

Redescription. Measurements: Body length 2.25–2.55 mm, width 1.30–1.51 mm. Vestiture: Body covered with recumbent scales and erect, oblong-lanceolate setae. Scales grayish-brown, oval, excised at apex, densely covering upper side of body and external surface of femora. Setae at pronotum suberect, at elytra erect, forming straight, sparse rows at interstriae, as long as 0.5–0.7 of interstriae width. Antennal funicle with thin sparse hairs. Antennal scape, tibiae, and tarsi with dense hairs and widened setae. Abdomen covered with recumbent hairs and piliform scales. Colouration: Body, legs and antennae brown.

Head: Rostrum conical, weakly narrowed from base to middle, as long as wide (RL/RW = 1.00–1.06). Pterygia well visible from above and strongly projecting from outline of rostrum. Epifrons parallel-sided, distinctly convex longitudinally, separated from vertex by weak, transverse depression. Vertex weakly convex. Eyes large, (VW/ ELD in males = 1.92–2.08, in females = 2.14–2.30), oval, weakly convex, situated weakly lower than level of vertex. Antennae: Scape weakly curved, evenly widened distally; funicular antennomeres: 1st and 2nd elongate, almost uniform; 3rd as long as wide; 4 th –7th transverse. Club egg-shaped, sharply separated from 7th funicular antennomere, 1st club antennomere sharply convex.

Thorax: Pronotum strongly transverse [PL/PW = 0.56–0.65 (0.60)], evenly and strongly convex at sides, sharply constricted anteriorly; disc almost flat, finely and densely punctate; punctures shallow. Elytra: oval or oblong-oval, weakly convex at sides; disc of elytra strongly convex (EL/EW = 1.22–1.40). Basal margin of elytra weakly concave. Striae narrow, deep, punctures weakly separated, 2x narrower than interstriae; spaces between striae situated distinctly lower than level of interstriae. Interstriae shiny, weakly convex. Legs: Femora weakly but distinctly swollen in middle part, tibiae slender and long, straight externally, widened in distal angle, weakly sinuate internally. Hind tibiae in male sharply sinuate at apical third and weakly mucronate. Second tarsomere strongly transverse, 3rd with broad lobes. Fifth fore tarsomere extending beyond apical lobes of 3rd by length of the lobes.

Abdomen: Anterior margin of 1st ventrite straight. Male 5th ventrite sharply convex, without subapical depression, with apical margin obtuse, in females rounded. Male genitalia: Aedeagus moderately sclerotized; median lobe 0.5x as long as apodemes, parallel-sided; endophallus with bifurcate endophallic sclerite and dense worm-shaped spiculate field. Ventral membranes distinctly extended beyond base of endophallus. Spermatheca: ramus large, corpus swollen.

Diagnosis. Brachysomus laticollis is closely related to B. transsylvanicus , differs in following characters: pronotum strongly transverse, its sides weakly convex; pterygia sharply projecting from outline of rostrum; eyes large [VW/ELD = 1.92–2.08 (males); 2.14–2.30 (females); in B. transsylvanicus VW /ELD = 2.30 (males) and 2.50– 2.60 (females)]; elytral interstriae sparsely setose; anterior margin of 1st ventrite straight, tibiae and tarsi sparsely setose; hind tibiae in male sharply sinuate internally and structure of aedeagus.

Distribution. Romania (Roşu, Suceava; Sebesu de Jos, SE of Sibiu; Balilesti near Campulung; Albota, S of Pitesti env.; Sinaia env., S of Brasov).

Bionomics. This species has been collected by P. Białooki and J. Szypuła in leaf litter in mature beech forests ( Fagus sylvatica ).

Type material. Holotype, ♂ (HNHM) ‘Verestorony [= Vöröstoronyi-szoros = Turnul Roşu Pass], Csiki’; Paratypes: 1♂, 18♀ (HNHM) as holotype; 1♂, 4♀ (HNHM), ‘Verestorony, Mihók’; 1♀ (NMPC), ‘Roterturm [= Turnul Roşu Pass], Transsilv.’

Additional material examined. ROMANIA: 1♂, 3♀, ‘Roterturm Pass [= Turnul Roşu Pass], Translv. Breit’ (ZMUH); 5♂, 25♀, ‘Burgenland, Roterturm Pass, leg. Liepolt’ (MMc); 1♀, ‘Kronstadt [= Braşov]’ (KUMN).

Figures

FIGURE 219. Brachysomus laticollis: A: aedeagus; B: tegmen; C: spermatheca; D: setae of elytra; E: hind tibia of male; F: scales of elytra.

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

FIGURES 43–50. Brachysomus, dorsal habitus: 43: B. transsylvanicus. 44: B. carpathicus female. 45: B. laticollis. 46: B. carpathicus male. 47: B. ellipticus. 48: B. kubanensis. 49: B. verae. 50: B. kovali.

FIGURES 112–117. Brachysomus, details: 112: B. transsylvanicus, head dorsal view. 113: B. transsylvanicus, head lateral view 114: B. carpathicus, head dorsal view. 115: B. carpathicus, head lateral view. 116: B. laticollis, head dorsal view. 117: idem, lateral view.