Brachysomus (Hippomias) polonicus Wanat & Mazur, 2005

Yunakov, Nikolai, 2022, A review of the genus Brachysomus Schoenherr (Coleoptera: Curculionidae: Entiminae), Zootaxa 5193 (1), pp. 1-165 : 69-70

Brachysomus (Hippomias) polonicus Wanat & Mazur, 2005

Figs. 120, 121 , 225 , 240A

Brachysomus polonicus Wanat & Mazur, 2005: 292 . Type locality: Poland, Hrubieszów. Białooki, 2007: 163.

Redescription. Measurements: Body length 2.00–2.25 mm, width 1.10–1.35 mm. Vestiture: Body covered with weakly excised scales and short spatulate setae; setae forming single row along elytral interstriae, 0.5x as long as interstrial width. Antennal scape with broad, rounded apically setae. Colouration: Body brown.

Head: Rostrum and head capsule form a cone. Pterygia sharply projecting from outline of rostrum. Dorsal margin of antennal scrobes reaching middle of rostrum. Rostrum as long as wide as or weakly shorter than wide (RL/RW= 1.00–1.08). Epifrons flat, parallel-sided, weakly widened apically from antennal insertion, without transverse depression. Vertex flat and broad. Eyes small, oval, hemispherical (VW/ELD = 2.8–3). Antennae: Scape evenly curved and widened distally; funicular antennomeres: 1st distinctly larger than other antennomeres; 2nd weakly longer than wide. 3rd–5th as long as wide, 6–7th transverse. Club widely-spindle-shaped, weakly separated from the funicle.

Thorax: Pronotum transverse (PL/PW in males = 0.81, in females—0.70–0.72) weakly convex at sides, widest posteriad of mid length; disc flat, in female with weak depressions; anterior constriction in male absent, in female weakly visible. Pronotum at base as wide as base of elytra. Elytra: oval (EL/EW =1.18–1.28 (1.23)), in female weakly convex at sides, in male almost parallel-side. Disc in male weakly convex, in female distinctly convex. Punctures small, shallow, weakly separated; spaces between punctures slightly depressed. Interstriae smooth, weakly convex. Base of elytra sinuate. Legs: Femora moderately swollen in middle part. Fore tibiae straight, not widened at apex. Hind tibiae in male weakly mucronate, not sinuate, external side straight. Second tarsomere transverse, 3rd with broad lobes. Fifth fore tarsomere extending beyond apical lobes of 3rd by length of the lobes.

Abdomen: Posterior margin of 1st ventrite weakly concave. Male 5th ventrite flat, with weak depression near apex. Male genitalia: Aedeagus slightly sclerotized; median lobe 1.2x shorter than apodemes, evenly narrowed apically, apex rounded; endophallus in basal half with sparse spiculate field, in apical half with small dense fields of spiculae. Spermatheca with very large ramus.

Diagnosis. Brachysomus polonicus is closely related to B. merkli , differing in body vestiture, elytral interstriae with short widened setae, rounded at apex, setae as long as 0.5 width of interstriae; body densely covered with small, grey, lanceolate scales; 3rd–7th funicular antennomeres transverse, in B. merkli 3rd–7th as long as wide; tarsi shorter and wider; 5th fore tarsomere extending beyond apical lobes of 3rd by more than length of the lobes; posterior margin of 1st ventrite weakly concave, in B. merkli strongly concave. In body shape, B. polonicus is similar to species of the genus Eurosphalmus Yunakov & Nadein, 2006 and Amicromias Reitter, 1912 , but the structure of the genitalia and absence of a constriction behind eyes (significant synapomorphy of Amicromias ) places this species in the genus Brachysomus .

Distribution. Poland, Ukraine (Lviv Prov., Kyiv Prov.), Romania (Braşov [first record], Tulcea [ Białooki, 2007]).

Bionomics. This species inhabits leaf litter in deciduous forests.

Material examined. POLAND: 3♂, 6♀ (Paratypes), ‘PL, GB03 Gródek, ad Hrubieszów, 25.vi.1994 leg. M. Wanat’ (ZIN). UKRAINE: 1♂, 1♀, Kyiv Prov., near Bila Tserkva, Alexandria park, Palieva Gora, bank of Ros Riv., 30.v.2001, V. Yu. Nazarenko leg. (SIZK); 1♂, 1♀, idem, but 25.v.2003, V. Yu. Nazarenko (SIZK); 1♀, idem, but 22.v.2004, V. Yu. Nazarenko leg. (SIZK). ROMANIA: 1♀, ‘Deubel, Kronstadt [= Braşov]’, ‘ kubanensis , det. Formánek’ (NMPC); 1♀, ‘Ganglb[auer], [18]95, Kronstadt [= Braşov]’, ‘ kubanensis , det. Formánek’ (NMPC).

Figures

FIGURE 225. Brachysomus polonicus: A: aedeagus; B: tegmen; C: endophallic sclerite; D: spermatheca; E: body; F: antenna; G: fore tarsus; H: ventrite III.

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.