Eubadura hokkaidensis, Tasaku & Maruyama, 2022

Tasaku, Yuto & Maruyama, Munetoshi, 2022, Taxonomy of the intertidal athetine genus Eubadura stat. nov. (Coleoptera: Staphylinidae: Aleocharinae) from Japan, with descriptions of two new species, Acta Entomologica Musei Nationalis Pragae 62 (1), pp. 137-144 : 143-144

Eubadura hokkaidensis sp. nov.

[Japanese name: Kuro-umihime-hanekakushi]

( Figs 1F, J ; 4 ; 5 )

Type material. Hඈඅඈඍඒඉൾ: ♂, [ JAPAN]: Hokkaidô, Abashiri-shi, Komaba, 20 VI 2021, Y. Tasaku. ( KUM). Pൺඋൺඍඒඉൾඌ: 23 exs, same data as holotype ( KUM, NMPC); 5 exs, same data as holotype, but 16. IX. 2020, Y. Tasaku ( KUM); 3 exs, Ishikari-shi, Atsuta-ku, Betsukari, mouth of Atsuta-gawa riv., 5. VI. 2021, Y.Tasaku ( KUM); 3 exs, Sôya, Esashi-tyô, 23 VII 2009, M. Ôhara ( KUM); 2 exs, Nemuro, Rausu-tyô, Azabu, 19 IX 2009, M. Ôhara, H. Yamamoto & M. Furuta ( KUM).

Description. Head, pronotum, elytra and abdomen almost black; antennae, mouthparts and legs blackish brown and yellowish brown. Head ( Fig. 1F ) as long as wide. Pronotum slightly transverse, about 1.1 times as wide as long, narrowed posteriorly; postero-lateral corner rounded; surface finely punctured, densely covered with setae, with 7 macrosetae along lateral margin. Scutellum with integument smooth and sparsely covered with setae. Elytra ( Fig. 1F ) as wide as pronotum; surface finely punctured, densely covered with setae, with 2–3 small macrosetae laterally. Hind wings reduced, about 1/3 as long as elytra. Abdomen oblong, widest around segments VI and VII; surface smooth; tergites II–VII densely covered with setae. Antennae ( Fig. 1F ) almost as long as head and pronotum combined; antennomere I long; antennomere II shorter than I; antennomere III slightly shorter than II; antennomeres IV–X moniliform, each almost as long as wide; antennomere XI long, almost twice as long as X.

Male. Male tergite VIII ( Fig. 4A ) densely covered with setae, with 4 pairs of macrosetae. Male sternite VIII ( Fig. 4B ) rounded on posterior margin, with 8 pairs of macrosetae. Median lobe of aedeagus as in Figs 4F–G ; in lateral view ( Fig. 4G ) apical lobe bent paramerally, much narrowed subapically, sinuate abparamerally and acutely narrowed apically. Paramere ( Fig. 4H ) with apical lobe of paramerite narrowed slightly.

Female. Female tergite VIII ( Fig. 4C ) densely covered with setae, with 4 macrosetae on each side; female sternite VIII ( Fig. 4D ) rounded on posterior margin, with 6 macrosetae on each side. Spermatheca ( Fig. 4E ) with basal part of stem once curved at apical and twice curved around base; capsule dilated apically, about 1/4 as long as stem, densely covered with wrinkles on internal side of apical 1/3.

Measurements (mm). Body length ca. 1.90–2.20; fore body length ca. 1.0–1.1; head width 0.36–0.38; pronotal length 0.32–0.38; pronotal width 0.38–0.40.

Differential diagnosis. This species can be distinguished from other Eubadura species by its black body color.

Etymology. Named after the type locality. Adjective.

Biology. The beetles were found under supratidal driftwood or seaweeds on sandy and gravel beaches.

Distribution. Japan: Hokkaidô.

Figures

Fig. 1. Habitus of Eubadura spp. A–C, G – E. akiensis (Sawada, 1990); D, H – E. yasukoae (Maruyama, Klimaszewski & Gusarov, 2008); E, I – E. onoi sp. nov.; F, J – E. hokkaidensis sp. nov. Scale bars: 1.00 mm

Fig. 4. Eubadura hokkaidensis sp. nov. A – male tergite VIII; B – male sternite VIII; C – female tergite VIII; D – female sternite VIII; E – spermatheca; F – median lobe, ventral view; G – median lobe, lateral view; H – paramere. Scale bars: 0. 1 mm.

Fig. 5. Known localities of Eubadura spp.Black circle – E. akiensis (Sawada, 1990); black triangle – E. yasukoae (Maruyama, Klimaszewski & Gusarov, 2008); black square – E. onoi sp. nov.; black star – E. hokkaidensis sp. nov.