Bisayodes hure Wakimura & Jałoszyński, 2023

Jałoszyński, Paweł & Wakimura, Ryotaro, 2023, A new genus, new species and new records of Eucinetidae in Japan and Taiwan (Coleoptera), Zootaxa 5351 (1), pp. 122-138 : 129-130

Bisayodes hure Wakimura & Jałoszyński sp. n.

( Figs 1, 5–22, 37, 41–42)

Type material studied. Holotype ( JAPAN): ♁, two labels: “ Japan: Hokkaido, Hiroo-gun, / Hiroo-cho , Bitatanunke [locality name repeated in Japanese characters] / 42.1667886;N 143.3203257;E / 2022. VI. 5. R.Wakimura leg.”, “ BISAYODES / hure Wakimura / & Jałoszyński / HOLOTYPUS ” ( HUMS) . Paratypes (23 exx.): 1 ♀, same data as for holotype ( HUMS) ; 4 ♀♀, same data as for holotype, except for 2022. X. 10 (cPJ, HUMS, NSMT) ; 1 ♁, same data as for holotype, except for 2022. X. 23 ( HUMS) ; 5 ♀♀, same data as for holotype, except for 2023. VII. 1 (cRW, HUMS) ; 6 exx., same data as for holotype, except for 2023. VII. 9 ( NSMT) ; 5 exx., same data as for holotype, except for 2023. VII. 9, N. Hirakizawa leg. ( HUMS) ; 1 ex., same data as for holotype, except for 2023. VIII. 31 (cRW) .

Diagnosis. As for genus, vide supra.

Description. Body of male ( Figs 1, 5–6) short oval, strongly convex dorsally and flattened ventrally, brown with strong reddish hue, appendages slightly lighter than body, setae slightly lighter than cuticle; BL 1.55 mm.

Head ( Figs 7–9, 11–12) broadest at eyes, HL 0.20 mm, HW 0.43 mm; lateral margins of head behind eyes in dorsal view straight, vertex and frons together weakly convex, strongly transverse; punctures on dorsum small, sharply marked and evenly distributed, separated by spaces 2–3 × as wide as diameters of punctures; setae short and sparse, suberect, directed anteriorly. Genae ( Fig. 8) with sparse setae along ventral margin of eye, postgenae asetose; gula and submentum asetose; mentum with short and sparse setae distributed along lateral and anterior marginal carinae.

Antennae ( Figs 10–12; in Fig. 10 shown in lateral view, in Figs 11 and 12 some parts of antennae are curved above and beneath the plane of illustration, so the shapes and proportions are affected; description was based on observations of specimens) distinctly longer than length of entire head capsule, AnL 0.38 mm; scape much broader than pedicel, about twice as long as broad, pedicel 2.5 × long as broad, antennomeres 3 and 4 subequal in length, each 1.5 × as long as broad, antennomere 5 about as long as broad; 6–8 each distinctly transverse and gradually increasing in width, 9–11 form loosely assembled club, 9–10 each transverse, 11 slightly elongate and about as long as 9–10 combined.

Pronotum ( Figs 1, 5) less convex than elytra, broadest at posterior corners, PL 0.35 mm, PW 0.75 mm. Anterior and lateral margins strongly and evenly rounded; posterior corners strongly projecting posteriorly and sharp-angled; posterior margin bisinuate, medially strongly and evenly convex. Punctures and setae on pronotal disc similar to those on frons and vertex. Hypomera asetose and virtually impunctate.

Elytra ( Figs 1, 5) together oval, broadest near anterior third and strongly narrowing posteriorly to broadly subtriangular apex; EL 1.00 mm, EW 0.85 mm, EI 1.18. Punctures and setae similar to those on frons and vertex; epipleura similarly punctate and setose as elytral disc.

Hind wings vestigial, each as long as only 1/5 of body width, about 3 × as long as wide.

Legs ( Figs 6, 20–22) short, robust, flattened dorsoventrally. Profemora with row of dense, thick setae along anterior margin in basal half of ventral surface ( Fig. 21); remaining legs unmodified. Apical spurs on mesotibiae ( Fig. 22) subequal in length, with rounded and slightly curved apices; spurs on metatibiae ( Fig. 20) slightly more unequal in lengths and gradually tapering to pointed apices.

Aedeagus ( Fig. 37) strongly elongate, AeL 0.40 mm; penis tapering towards subtriangular apex, with undulate lateral margins; parameres massive, at base broader than penis, tapering towards rounded apices.

Female. Externally indistinguishable from male. BL 1.55–1.70 mm; HL 0.20 mm, HW 0.45 mm, AnL 0.43– 0.45 mm; PL 0.35–0.38 mm, PW 0.75–0.78 mm; EL 1.00– 1.13 mm, EW 0.85–0.93 mm, EI 1.18–1.25.

Distribution. Northern Japan: Hokkaidô.

Etymology. The adjective hure is taken from the Ainu-itak language of Ainu people that inhabit Hokkaidô; its meaning is “red”, referring to the reddish hue of adult beetles.

Remarks. Specimens used in this study were collected from leaf litter under and around Sasa sp. ( Poaceae ), Quercus crispula Blume ( Fagaceae ) and other plants in cool-temperate deciduous broadleaved forests ( Figs 41–42). Living individuals of Bisayodes hure were observed making leaping movements, as other Eucinetidae .