Brachysomus (Brachysomus) ornatus Stierlin, 1892

Yunakov, Nikolai, 2022, A review of the genus Brachysomus Schoenherr (Coleoptera: Curculionidae: Entiminae), Zootaxa 5193 (1), pp. 1-165 : 24-25

Brachysomus (Brachysomus) ornatus Stierlin, 1892

Figs. 41, 42 , 89, 90 , 181 , 235B

Brachysomus ornatus Stierlin, 1892: 366 . Type locality: Romania, Bihar Mountain Range; Dalla Torre et al. 1937: 174.

Redescription. Measurements: Body length 2.10–2.90 mm, width 1.40–1.85 mm. Vestiture: Body and head densely covered with very small round, weakly shiny scales, feebly setose. Sides of pronotum with rather dense scale coverage, interstriae densely setose. Setae suberect, spatulate, very short on elytra, ca. 1/5 width of interstriae. Disc of pronotum with oblong-oval scales. Antennae, legs, and abdomen with slender light piliform and lanceolate scales, and widened obtuse setae. Colouration: Integument of body and appendages brown, appendages slightly paler. Background scaling of head and body grey-brown to dark-brown with slight pearly shine. Elytra with brown spotted pattern. Disc of pronotum with light median longitudinal stripe.

Head: Rostrum as long as wide, parallel-sided, with lateral margins in line with lateral margins of temples. Antennal scrobes distinctly visible from above, deep, directed to ventral margin of eye, not reaching ventral side of rostrum. Pterigia not projecting from outline of rostrum. Epistome flat, delimited from epifrons by very thin Ushaped epistomal carina. Epifrons narrowed from base to midlength, from midlength to apex parallel-sided, weakly longitudinally convex with very thin weakly visible median carina (observable if scales removed). Epifrons very weakly separated from vertex by transverse depression, which visible only in lateral view. Vertex weakly convex, finely punctate. Eyes oval, weakly convex, highest at middle (FW/ ELD = 1.7). Antennae: Scape thin, nearly straight, evenly widened distally; funicular antennomeres: 1st 2x longer than wide; 2nd–5th moniliform, as long as wide; 6th and 7th transverse; club broadly spindle-shaped or oblong and egg-shaped.

Thorax: Pronotum transverse [PL/PW = 0.64–0.73 (0.67)], widest posteriad of mid length, gently and evenly convex at disc and sides, evenly constricted anteriorly and posteriorly, densely, shallowly punctate; disc without lateral depressions. Elytra: highly variable in shape, in males globose, in females broadly-oval, strongly convex at disc and sides (EL/EW = 1.2–1.3). Mesonotum and base of elytra vertical. Elytral interstriae weakly convex, shiny, 2x wider than striae. Punctures distinct, broadly separated; spaces between punctures concave, somewhat narrower than diameter of puncture. Legs: Femora moderately swollen in middle section. Fore tibia straight, with apical external angle not protruding. Hind tibiae without mucro. Second tarsomere weakly transverse. Fifth fore tarsomere extending beyond apical lobes of 3rd by 0.75 length of the lobes.

Abdomen: First ventrite with posterior margin deeply sinuate. Male 5th ventrite flat, apical margin obtuse, with bilateral bunches of pale hairs. Female 5th ventrite flat, apical margin widely rounded. Male genitalia: Aedeagus slightly and evenly sclerotized, median lobe 0.9x as long as apodemes, parallel-sided along most length, evenly narrowed only along apical 1/4. Apex not attenuate, not dentate (in lateral view). Endophallus with two spiculate fields in distal half and one large bifurcate sclerite. Ventral membranes triangular, slightly sclerotized. Parameres well developed, free, as long as width of tegminal ring; posterior margin of basal piece sinuate. Spermatheca: Ramus and collum connate at base, ramus 2x as long as collum.

Diagnosis. From B. echinatus it differs by the rather short erect setae and the broad dense scales at the pronotum and elytra, brown spotted pattern on the elytra. From B. strawinskii it differs by the flat male 5th ventrite, epifrons without median longitudinal sulcus, not separated from vertex by transverse depression, large, weakly convex eyes, spotted pattern on the elytra, and structure of genitalia.

Distribution. Romania: South Carpathians (Bihar Mountain Range).

Bionomics. The species inhabits leaf litter in mountain deciduous forests around 500 m a.s.l.

Type material. Lectotype, ♂ (here designated) (SDEI): ‘Hungaria (Com. Bihar.) Dr. Fleischer (printed)’; ‘ ornatus Type (hand written)’; ‘coll. Stierlin (printed)’; ‘Böhman (hand written)’; ‘ B. ornatus Sti. (hand written)’; ‘ ornatus (hand written), det. Formánek (printed)’; ‘Syntypus (red label, printed)’; ‘coll. DEI Eberswalde’; ‘Genitalpräparat, M. Košťál, 1985’. Paralectotype, ♀: ‘Hungaria (Com. Bihar.) Dr. Fleischer (printed)’; ‘ ornatus Type (hand written)’; ‘coll. Stierlin (printed)’; ‘Syntypus (red label, printed)’; ‘coll. DEI Eberswalde’.

Additional material examined. ROMANIA: 1♂, 1♀, ‘Hungaria Com. Bihar [= Munţii Bihorului = Bihar Mountain Range]. Dr. Fleischer’ (SDEI); 1♀, ‘Hu.[ngaria], Bihar, Szegyestel E. Bokor’ (HNHM); 1♀, ‘Ung.[arn], Bihar, Rev’ (MTD); 1♂, 1♀, ‘Romania, Mt. Pad. Craiului: val. Sohodol, p. Jurcanilor env., 550 m, 9.vi.1995, P. Moravec’ (BRc); 1♀, ‘Romania, c. Bihar, Bata env., p. Fînaţe, 12.vii.[19]81 P. Moravec’ (BRc); 1♀ ‘Transsylvania, Hargita m., Homoródfürdő [Băile Homorod, Harghita], 24.v.1996, I. Koks & A. Podlussány leg. (HNHM); 1♂, 1♀, ‘Rézbánya, János, E. Bokor leg. (HNHM).

Figures

FIGURE 181. Brachysomus ornatus: A: aedeagus, dorsal and lateral view; B: tegmen; C: spermatheca; D: tergite VIII; E: epistome.

FIGURE 235. Occurrence map of Brachysomus: A: B. echinatus; B: Brachysomus s. str.

FIGURES 37–42. Brachysomus, dorsal habitus: 37, 38: B. echinatus. 39: B. strawinskii 40: idem, female. 41: B. ornatus, male. 42:—idem, female.

FIGURES 87–94. Brachysomus, details: 87, 88: B. echinatus. 89, 90: B. ornatus. 91, 92: B. strawinskii. 93, 94: B. fremuthi.