Brachysomus (Hippomias) ellipticus Yunakov, 2006

Yunakov, Nikolai, 2022, A review of the genus Brachysomus Schoenherr (Coleoptera: Curculionidae: Entiminae), Zootaxa 5193 (1), pp. 1-165 : 71

Brachysomus (Hippomias) ellipticus Yunakov, 2006

Figs. 47 , 118, 119 , 226 , 229A , 240B

Brachysomus ellipticus Yunakov, 2006: 312 . Type locality: Aibga Mountain Range.

Redescription. Measurements: Body length 2–2.9 mm, width 1.05–1.65 mm (in holotype 2.25 and 1.25 mm). Vestiture: Head, pronotum and elytra densely covered with grey and brown lanceolate scales. Epistome without scales. Elytra with degraded brown, spotty scale pattern and short suberect lanceolate setae at interstriae. Antennal scape, outer surface of femora and tibiae densely covered with scales and erect setae. Antennal funicle and interior side of tibiae with long pale hairs. Setae as long as 1/2 interstrial width. Head and pronotum almost without erect setae. Abdomen sparsely covered with piliform scales and hair. Colouration: Body light brown to dark-brown, antennae and legs usually light brown.

Head: Rostrum conical, weakly elongate (RL/RW = 1.12–1.21). Pterygia clearly visible in dorsal view, strongly projecting from outline of rostrum. Epifrons parallel-sided, vertex 1.66x as wide as width of opifrons at level of antennal insertion, weakly convex longitudinally, with weak median longitudinal sulcus, separated from vertex by shallow transverse depression. Postepistome depressed; epistome delimited by V-shaped carina. Eyes small (VW/ELD = 2.40–2.81), oblong-oval, weakly convex, situated lower than level of vertex by 0.87 ETD. Vertex flat, distinctly longitudinally punctate under scales. Antennae: scape evenly curved and widened distally, at apex 3.5–4.0x wider than at base, extending beyond anterior margin of pronotum. Funicle noticeably widened distally; funicular antennomeres: 1st (L/W = 2.25) and 2nd (L/W = 2.00) elongate, 1st 1.5x as long as 2nd, 3rd as long as wide, 4 th –7th transverse; club egg-shaped.

Thorax: Pronotum slightly transverse (PL/PW = 0.75–0.83), widest at middle, evenly convex at disc and sides, noticeably constricted anteriorly and posteriorly, finely and densely granulate and shallowly punctate. Disc with shallow lateral depressions, sometimes with shallow medial groove. Elytra: in males distinctly oblong-oval, in female oval, (EL/EW = 1.36–1.38), evenly convex at disc and sides. Punctures shallow, noticeably separated; spaces between punctures somewhat narrower than diameter of puncture, situated deeper than interstrial level. Interstriae convex, shiny, as wide as striae. Base of elytra slightly sinuate. Legs: Femora moderately swollen in middle part. Fore tibiae straight from the outside, S-shaped interiorly. Hind tibiae in male weakly sinuate interiorly, distinctly mucronate, in females slightly narrowing apically, medial margin of hind tibiae obtuse. First tarsomere triangular, 2nd as long as wide. Fifth fore tarsomere extending beyond apical lobes of 3rd by 0.58 length of the lobes.

Abdomen: Male 5th ventrite slightly impressed at apical part, evenly punctate, apical margin slightly sinuate. 5th ventrite in female without depression, straight at apex. Male genitalia: Aedeagus weakly sclerotized, median lobe as long as apodemes, ventral side of median lobe membranous, except for distal part. Ventral membranes slightly sclerotized. Endophallus with fields of tubercle-like spiculae and with small lobe-shaped sclerite. Spiculae distinctly round apically. Spermatheca: corpus swollen, ramus longer than collum.

Diagnosis. Brachysomus ellipticus is closely related to B. kubanensis , clearly differing by the elongate body shape (EL/EW = 1.36–1.38, in B. kubanensis EL /EW = 1.21–1.24), sinuate unsharpened medial margin of male hind tibia, smaller eyes (VW/ELD = 2.40–2.81, in B. kubanensis VW /ELD = 1.66–2.07); structure of aedeagus: lateral margins of ventral wall of median lobe slightly sclerotized, and proximal part of endophallus without large sclerites.

Distribution. Western Caucasus: Aibga Mountain Range and Atshishkho Mountain Range ( Yunakov 2006).

Bionomics. This species inhabits leaf- and grass-litter in mountain forests and alpine meadows from 600–2500 m a.s.l.

Material examined. RUSSIA: Western Caucasus. Holotype ♂ (ZIN), Krasnodar Terr., Aibga Mountain Range, 1300–1700 m, 11.VI.1997 G.E. Davidian leg. Paratypes: 25♂, 19♀, as holotype (ZIN); 1♂, 2 ♀, the same data as holotype, but 600–1300 m, 10.VI.1997 (ZIN); 1♂, idem, but 12.VI.1997 (ZIN); 1♀, idem, but 7.viii.1991 (ZIN); 4♂, idem, 1000 m, broad-leaved forest with Fagus orientalis , 10.VI.2001 R.V. Filimonov leg. (ZIN, FRc); 1♀, idem, 1400 m, 14.VI–23.viii.1987 I.А. Belousov leg. (ZIN); 1♂, 3♀, idem, 500 m, 29.IV–11.IX.1992 А.G. Koval leg. (ZIN); 1♂, idem, 1700 m, 1.vi.1995 A.I. Roubchenya leg. (ZIN); 1♂, 3 ♀, idem, 16.v–5.x.1988 H. Hippa, P. Vilkamaa leg.; 1♂, Fisht Massif, near Pshekho-Su Mt., 26.VI.1997 G.E. Davidian leg. (ZIN); 4♂, 4♀, Atshishkho Range: 1600–2000 m, subalpine zone, 4.viii.1991 G.E. Davidian leg. (ZIN); 5♂, 1♀, idem, 2500 m, 24.vii.2001 G.E. Davidian leg. (ZIN); 1♂, 2 ♀, idem, 10.vi.1997 А.G. Koval leg. (ZIN); 4♂, 5 ♀, near Krasnaya Polyana, Mzymta Riv. Canyon, 18.vii–15.viii.1986 А.G. Koval leg. (ZIN); 3♂, 1♀, S spurs of Chugosh Range, Achipse Riv. Left bank, 1300 m, 21.vii–10.viii.1994 А.Yu. Solodovnikov leg. (Sc); 1♀, NW slope of Iegosh Mt., 23.v.1996 G.E. Davidian leg. (ZIN); 9♂, 8 ♀, Fanagoreiskaya, 2 km NW of Schetka Mt., Fagus forest, 6–8.vi.1997 G.E. Davidian leg. (ZIN); 7♂, 1♀, ‘Cauc. Occ., Krasna Polana, VIII, Dr. Lgocki’, ‘ Br. Kubanensis ’ (ZIN, MTD); 2 ♀, ‘Krasna Poljana’ (NMPC).

Figures

FIGURE 226. Brachysomus ellipticus: A: aedeagus; B: tegmen; C: spermatheca; D: body; E: hind tibia of male; F: ventrites.

FIGURE 229. Endophallus. A: Brachysomus kovali; B: Brachysomus ellipticus.

FIGURE 240. Occurrence map of Brachysomus 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 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.