Brachysomus (Hippomias) sulcatus Yunakov, 1999

Yunakov, Nikolai, 2022, A review of the genus Brachysomus Schoenherr (Coleoptera: Curculionidae: Entiminae), Zootaxa 5193 (1), pp. 1-165 : 67-68

Brachysomus (Hippomias) sulcatus Yunakov, 1999

Figs. 122, 123 , 222 , 240A

Brachysomus sulcatus Yunakov, 1999: 13 . Type locality: Ukraine, Chatyr-Dagh Range; Białooki, 2007: 164.

Redescription. Measurements: Body length 1.65–2.35 mm, width 0.9–1.3 mm. Vestiture: dorsal surface head, pronotum, and elytra evenly covered with grey piliform scales and slender, obtuse, erect setae. Interstriae with straight row of setae, as long as setae width or weakly longer. Colouration: Body, legs and antennae brown.

Head: Rostrum almost parallel-sided, as long as wide. Pterygia well developed and visible from above, not hidden by lateral margins of epifrons, weakly projecting from outline of rostrum. Epifrons convex longitudinally, narrow, with moderate median longitudinal sulcus, at level of antennal insertion 2x narrower than vertex, separated from it by moderate transverse depression. Vertex flat or weakly convex. Head capsule densely and coarsely punctate. Eyes small, round, hemispherically convex, with large facets, strongly projecting from outline of head capsule. Antennae slender, scape strongly convex in middle, sharply widened in distal 1/3, here 2.5x wider than at base. Funicle evenly widened distally; funicular antennomeres: 1st and 2nd slightly elongate, 1st moderately longer and wider than 2nd; 3rd as long as wide, 4 th –7th transverse, 7th noticeably larger than three previous antennomeres and 2x narrower than club. Club egg-shaped sharply set off from funicle.

Thorax: Pronotum transverse [PL/PW = female: 0.83–0.92 (0.86); male: 0.83], evenly convex at sides, widest at middle; disc weakly, densely, and coarsely punctate. Elytra: oval, evenly convex at sides; disc weakly convex or flat. Striae shallow, in basal half 1.7–2x narrower than interstriae; punctures weakly separated. Interstriae flat, shiny. Legs: Apex of fore tibiae weakly widened. Hind tibiae in male weakly mucronate, not sinuate internally.

Abdomen: First ventrite with posterior margin deeply sinuate. Male 5th ventrite evenly convex, without depression on posterior part. Male genitalia: Aedeagus slightly sclerotized; median lobe 0.3x as long as apodemes, with apex evenly rounded; tegmen with well developed parameres. Spermatheca: ramus large, corpus swollen, collum very short.

Diagnosis. Brachysomus sulcatus is closely related to B. alexeevi , differing by longer erect setae (nearly as long as interstrial width; in B. alexeevi : setae as long as 2/3 interstrial width), shape and size of elytral scales which are longer and uniformly piliform (in B. alexeevi : body evenly covered with light, fine, small, piliform and lanceolate scales), strongly curved antennal scape and structure of aedeagus.

Distribution. Ukraine (Crimean Mountains)

Bionomics. This species inhabits leaf litter in mountain Fagus forests of the southern slopes of the Chatyr- Dagh Mountain Range around 1000 m a.s.l., feeding on saprotrophic fungi Oudemansiella mucida , Coniophora sp. , Peniophora sp. , Coriolus sp. , (Basidiomycetes); Cytospora sp. , Pullularia pullulans (Deuteromycetes) and Valsa sp. (Ascomycetes) ( Yunakov 1999).

Type material. UKRAINE: Holotype ♂, (ZIN) ‘Crimea, S slope Chatyr-Dagh, near Angar-Burun, 5 km W of Angarsky Pass, 14.v.1999, N. N. Yunakov’. Paratypes: 7♂, 8♀ (ZIN, KUMN) ‘Crimea, S slope Chatyr-Dagh, near Angar-Burun, 5 km W of Angarsky Pass, 14.v.1999, N.N. Yunakov’; 2♂ (ZIN) ‘Crimea, S slope Chatyr-Dagh, near Angar-Burun, 5 km W of Angarsky Pass, 14.v.1999, A.N. Drogvalenko leg.

Additional material examined. 2♂, 2♀ (ZIN) ‘Crimea, S slope Chatyr-Dagh, near Angar-Burun, 5 km W of Angarsky Pass’, 15.v.2000, N.N. Yunakov leg.; 3♂ (HNHM, ZMAN) Iaila-Gebirge, Winkler leg. 1♀ (ZIN) Bakhchisarai Distr., Sokolyne env., Fagus forest, pitfall trap 22.vi.1992.A.G. Koval leg.; 3♂ (KUMN) Cape Martian Nature Reserve, sifting leaf litter, 24.iv.2012, N.N. Yunakov; 1♂ (KUMN) idem, 28.iv.2012.

Figures

FIGURE 222. Brachysomus sulcatus: A: aedeagus; B: tegmen; C: spermatheca; D: body; E: antenna; F: scales of elytra.

FIGURE 240. Occurrence map of Brachysomus subgenus Hippomias.

FIGURES 118–123. Brachysomus, details: 118: B. ellipticus, head dorsal view. 119: B. ellipticus, head lateral view 120: B. polonicus, head dorsal view. 121: B. polonicus, head lateral view. 122: B. sulcatus, head dorsal view. 123: B. sulcatus, head lateral view.