Euthiconus nopporoensis

Jałoszyński, Paweł, 2019, The first record of Euthiconus Reitter in Japan, with comparative notes on remaining Palaearctic species (Coleoptera, Staphylinidae, Scydmaeninae), Zootaxa 4691 (1), pp. 78-82: 78-82

publication ID

https://doi.org/10.11646/zootaxa.4691.1.6

publication LSID

lsid:zoobank.org:pub:A1A6F521-A404-4746-956F-4619CA8C79B2

persistent identifier

http://treatment.plazi.org/id/03F45052-D779-FFFB-D3D2-C180FAA0CBF2

treatment provided by

Plazi

scientific name

Euthiconus nopporoensis
status

sp. n.

Euthiconus nopporoensis  sp. n.

( Figs 1–2View FIGURES 1–6, 7, 10–13View FIGURES 7–17)

Type material. Holotype: Japan (Hokkaido): ♂, two labels: " JAPAN, HOKKAIDO / Osawaguchi, / Nopporo Forest / Park, Ebetsu City / X–XI 2005, leg. T. / Lackner" [white, printed]; " EUTHICONUS  / nopporoensis  m. / det. P. Jałoszyński, 2019 / HOLOTYPUS " [red, printed] ( MHNG)  . Paratype: ♀, same data as for holotype ( MHNG)  .

Diagnosis. Antennomere III distinctly transverse; male protrochanters unmodified; aedeagus in ventral view with rapidly narrowed, elongate apical region with rounded distal margin.

Description. Body of male ( Fig. 1View FIGURES 1–6) elongate and moderately slender, strongly convex, moderately light brown with indistinctly lighter appendages; setae yellowish; BL 1.10 mm.

Head ( Fig. 2View FIGURES 1–6) transverse, broadest at large, strongly convex and finely faceted eyes, HL 0.13 mm, HW 0.23 mm; vertex and frons confluent, their median region distinctly impressed between arcuate (anteriorly convex) posterior margin of vertex and area between supraantennal tubercles. Punctures on frons and vertex fine, inconspicuous, cuticle glossy; setae sparse, moderately long, suberect. Antennae slender, weakly thickened distad; AnL 0.58 mm, antennomere I about twice as long as broad, II weakly elongate, III distinctly transverse, IV about as long as broad, V–VIII each indistinctly elongate, IX and X as long as broad, XI distinctly shorter than IX–X combined, about 1.8 × as long as broad.

Pronotum ( Fig. 2View FIGURES 1–6) subconical and elongate, broadest at base and weakly narrowing anterad; PL 0.28 mm, PW 0.23 mm. Anterior and posterior margins nearly straight; sides weakly rounded near anterior third and nearly straight posteriorly; pronotal base with shallow transverse groove and a pair of distinct, strongly elongate lateral impressions near each hind angle. Punctures on pronotal disc fine and inconspicuous, cuticle glossy; setae moderately long, sparse and suberect (more so on sides, especially in anterior half).

Elytra together oval, broadest slightly in front of middle, evenly convex; EL 0.60 mm, EW 0.43 mm, EI 1.41; humeral calli distinct but small; elytral apices separately broadly rounded. Punctures on elytra slightly more distinct than those on pronotum but fine, shallow and with diffuse margins; setae indistinctly thicker than those on pronotum, moderately dense and suberect.

Pygidium about as wide as long; length 010 mm.

Legs ( Figs 1View FIGURES 1–6, 7View FIGURES 7–17) long and slender; protrochanter ( Fig. 7View FIGURES 7–17) unmodified.

Aedeagus ( Figs 10–13View FIGURES 7–17) slender, AeL 0.30 mm; median lobe in ventral view bottle-shaped, subcylindrical between basal and apical 1/4, gradually narrowed toward truncate base and abruptly narrowed in subapical region, apical margin rounded; endophallic structures not observable; parameres broad and barely discernible, translucent, only their base at each side of dorsal foramen well-visible as transverse ridge.

Female. Similar to male, also with impressed median area on frons and vertex; BL 1.09 mm; HL 0.13 mm, HW 0.23 mm, AnL 0.53 mm; PL 0.28 mm, PW 0.25 mm; EL 0.59 mm, EW 0.43 mm, EI 1.38.

Distribution. Northern Japan, Hokkaido, near Sapporo.

Etymology. After the type locality, the Nopporo Forest Park.

Remarks. Among Palaearctic species, Euthiconus nopporoensis  is most similar to E. lustrificus  ( Figs. 3–4View FIGURES 1–6, 8, 14–15View FIGURES 7–17). Adults of these Far Eastern species share a similar shape of the pronotum ( Figs 2, 4View FIGURES 1–6), unmodified male protrochanters ( Figs 7, 8View FIGURES 7–17), and a similar shape of the aedeagus ( Figs 10–15View FIGURES 7–17). Adults differ in the following characters: body length ( E. nopporoensis  is slightly smaller than E. lustrificus  ); the shape of the antennomere III (distinctly transverse in E. nopporoensis  vs. as long as broad in E. lustrificus  ); setae on the pronotum (sparser in E. nopporoensis  ( Fig. 2View FIGURES 1–6) and denser in E. lustrificus  ( Fig. 4View FIGURES 1–6)); and the shape of the aedeagus in ventral view (rapidly narrowed in the subapical region in E. nopporoensis  ( Fig. 10View FIGURES 7–17) vs. evenly narrowed in E. lustrificus  ( Fig. 14View FIGURES 7–17)). The distribution of the third Palaearctic species is strictly European. Euthiconus conicicollis  ( Figs 5–6View FIGURES 1–6, 9, 16–17View FIGURES 7–17) differs from its Far Eastern congeners in having a distinctly larger body, the pronotum more strongly narrowing anterad ( Fig. 6View FIGURES 1–6), conspicuously modified male protrochanters ( Fig. 9View FIGURES 7–17), and the aedeagus with broadened apical region ( Figs 16–17View FIGURES 7–17).

MHNG

Museum d'Histoire Naturelle