Brachysomus (Brachysomus) erinaceus ( Fabricius, 1801 )

Yunakov, Nikolai, 2022, A review of the genus Brachysomus Schoenherr (Coleoptera: Curculionidae: Entiminae), Zootaxa 5193 (1), pp. 1-165 : 45

Brachysomus (Brachysomus) erinaceus ( Fabricius, 1801)

Figs. 136, 137 , 150, 151 , 200 , 238B

Curculio erinaceus Fabricius, 1801: 527 № 117. Type locality: ‘Austria’.

Trachyphloeus villosulus Germar, 1824: 406 . Type locality: ‘Austria’; Formánek 1905: 179 ( Brachysomus ); Dalla Torre et al 1937: 175; Smreczyński 1966: 85; Dieckmann 1980: 258; Yunakov 1998: 37; Podlussány 2001: 239; Wanat & Mazur 2005: 297.

Redescription. Measurements: Body length 2.00–2.65 mm, width 1.1–1.55 mm. Colouration: Body brown to light-brown, legs and antennae yellowish-brown. Vestiture: Body sparsely covered with light grey, ovate, recumbent scales and very long, slender, obtuse, erect setae, forming streight rows in interstriae of elytra, distinctly longer than width of interstriae.

Head: Rostrum weakly transverse, parallel-sided, Antennal sockets partly visible in dorsal view. Pterygia weakly projecting from outline of rostrum. Antennal scrobes sharply developed, deep, directed to ventral margin of eye, reaching ventral side of rostrum. Epistome flat, delimited from epifrons by thin V-shaped carina. Epifrons parallel-sided, flat, with thin median carina, without median longitudinal sulcus, without transverse depression. Vertex flat, finely striate and longitudinally punctate. Eyes oval (VW/ELD = 1.92–2.3), strongly convex, highest at middle. Antennae: Scape gently curved, strongly widened along distal 1/3; at apex 3.3x wider than at base. funicular antennomeres: 1st and 2nd elongate; 1st larger than 2nd; 3rd–5th as long as wide, or weakly transverse, 6th and 7th strongly transverse; club egg-shaped.

Thorax: Pronotum transverse [PW/PL = 0.68–0.76 (0.72)], widest at middle, gently and evenly convex at sides; disc weakly convex, constricted anteriorly and posteriorly, densely, shallowly punctate; spaces between punctures very narrow, forming reticular sculpture. Elytra: ovate, in female broad-ovate, strongly convex at disc and sides. Interstriae of elytra weakly convex, 3.5x wider than striae. Punctures well separated. Spaces between punctures very weakly concave, somewhat narrower than diameter of puncture. Legs: Fore tibiae straight, with apical external angle not protruding. Hind tibiae in male with strong mucro. Second tarsomere weakly transverse. Fifth 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, truncate, with scattered pale hairs. Male genitalia: Aedeagus heavily sclerotized through entire length. Median lobe as long as apodemes, evenly narrowed apically, strongly dorsoventrally curved, with ventral side mostly sclerotized, apex flat and strongly acute. Endophallus with robust, elongate spicules. Ventral membranes lanceolate, slightly sclerotized. Parameres well developed, fused at base, as long as width of tegmenal ring, posterior margin of basal piece sinuate. Spermatheca: ramus and collum connate at base, collum 2x as long as ramus.

Diagnosis. Brachysomus erinaceus differs from to B. setiger by the strongly elongate erect setae, the sparse vestiture of the elytra in female, less transverse pronotum (W/L = 1.36–1.52, in B. setiger — 1.26–1.30) and shape of aedeagus.

Distribution. Central Europe and western part of Eastern Europe.

Bionomics. This species inhabits leaf- and grass litter of dry steppe slopes and xerothermic forests ( Dieckmann 1980).

Remarks. This species is well-known as B. villosulus ( Germar, 1824) but Curculio erinaceus Fabricius, 1801 has precedence.

Type material. Lectotype, ♀ (ZMUC), labels: “ erinaceus ” (handwritten), ‘LECTOTYPE / Curculio erinaceus Fabricius / Alonso-Zarzaga des. 2008’.

Additional material examined. AUSTRIA: 1 spm. (ZIN) ‘Umgebung Wien, Reitter (Leder) leg.’, N48.22592, E16.273134. MOLDOVA: 1 spm. (ZIN) Bender, 15.v.1967, V.I. Talicki, sweeping, N46.853207, E29.420047, glade in forest; 1 spm. (ZIN) Cahul, Huluboaia, 7.vi.1967, V.I. Talicki, N46.065797, E28.328641; 1 spm. (ZIN) Gagauzia, Etulia, 16.v.1995, Poiras A., sweeping, N45.535905, E28.444374, meadow; 1 spm. (ZIN) Chisinau, Botanical Garden, 24.v.1995,A. Poiras, N46.974759, E28.883341; 2 spm. (ZIN) NE of Bender, left bank of Dniester, 10.v.1996, A.V. Gontarenko, N46.843883, E29.497182. UKRAINE: 1 spm. (ZIN) Ternopil Prov., Pidvolochysk, Medobory Nature Reserve, Hostra Mt., 31.v.1998, V.Yu. Nazarenko, N49.39529, E26.08367; 1 spm. (ZIN) Zaporizhia Prov., Huliaipole, 30.vi.1999, A.G. Moseiko, N47.66396, E36.2682.

Figures

FIGURE 200. Brachysomus setiger: A: body of male; B: scales antenna of male; C: scales of elytra; D: aedeagus; E: tegmen; F: spermatheca.

FIGURE 238. Occurrence map of Brachysomus s. str.

FIGURES 136–141. Brachysomus, main view. 136: B. erinaceus, male. 137: B. erinaceus, female. 138: B. setiger, male. 139: B. setiger, female. 140: B. hegyessyi, male. 141: B. hegyessyi, female.

FIGURES 148–155. Brachysomus, head and pronotum: 148: B. armatus, dorsal view. 149: B. boroveci, dorsal view. 150: B. erinaceus, dorsal view. 151: idem, lateral view. 152: B. hegyessyi. 153: idem, lateral view. 154: B. setiger, dorsal view. 155: idem, lateral view.