Paraneseuthia zanetae, Jałoszyński, 2019

Jałoszyński, Paweł, 2019, Filling gaps in distribution of Japanese Paraneseuthia Franz: discovery of a new species on Okinawa-jima (Coleoptera, Staphylinidae, Scydmaeninae), Zootaxa 4674 (2), pp. 296-300 : 297-300

Paraneseuthia zanetae sp. n.

( Figs 1–6 )

Type material. Holotype: JAPAN (OKINAWA Pref.): ♂, two labels: "JAPAN, OKINAWA Island / Rd. 58 near Michi-no-eki Kyoda , / roadside, 08.02.2019 / sifted around standing trunk of / dead Vernicia tree / leg. P. JAŁOSZYŃSKI" [white, printed] ; " PARANESEUTHIA / zanetae m. / det. P. Jałoszyński, 2019 / HOLOTYPUS " [red, printed] ( NSMT).

Diagnosis. Body small (BL <1 mm); protibia in male with angulate mesal expansion and tiny denticle near middle; aedeagus with subtriangular, broadly rounded and not bifurcate apical portion of median lobe, with a pair of conspicuously large, strongly asymmetrical and twisted / recurved sclerites protruding from ostium; parameres in lateral view broad, but each with tapered apex.

Description. BL 0.78 mm. Body of male ( Fig. 1 ) elongate and moderately convex, dark brown, legs, antennae and palps distinctly lighter, setae yellowish.

Head short and transverse, broadest at large, strongly convex and coarsely faceted eyes, HL 0.08 mm, HW 0.20 mm; vertex and frons confluent and evenly, weakly convex; supraantennal tubercles poorly elevated. Punctures on head very fine, inconspicuous, cuticle glossy; setae very short, sparse and suberect. Antennae moderately slender, with indistinctly delimited trimerous club, AnL 0.35 mm, antennomeres I–II elongate, III–VIII each about as long as broad (some barely noticeably transverse), IX and X each slightly transverse, XI broader than X, subequal in length to IX–X together, about 1.7× as long as broad.

Pronotum approximately quadrangular, with rounded anterior margin, broadest near anterior third; PL 0.23 mm, PW 0.28 mm. Anterior margin rounded, sides rounded (in anterior third more strongly than in posterior half), posterior corners distinct but obtuse-angled and blunt; posterior margins arcuate; pronotal base with two lateral pairs of small pits, inner pair not connected by groove. Punctures on pronotal disc fine and inconspicuous, cuticle glossy; setae moderately long, sparse and suberect.

Elytra oval, broadest between middle and anterior third, evenly convex; EL 0.48 mm, EW 0.38 mm, EI 1.27; humeral calli distinct but small, basal impressions indistinct; apices separately, broadly rounded. Punctures on elytra much more distinct than those on head and pronotum, small, with diffuse margins, dense, in anteromedian portion of elytra separated by spaces equal to or smaller than diameters of punctures, on sides and toward apices punctures become smaller and shallower; setae longer than those on pronotum, moderately dense and suberect. Hind wings well developed.

Metaventrite flattened, not impressed.

Legs moderately long and slender; protibiae distinctly bent near middle, with mesal angulate expansion bearing a tiny denticle.

Aedeagus ( Figs 2–5 ) stout, AeL 0.20 mm; median lobe in ventral view broadest in distal region of basal capsule, apex of median lobe subtriangular, broadly rounded; endophallus with a pair of conspicuously large and asymmetri- cal lateral sclerites protruding from ostium, each recurved and additionally twisted; parameres in lateral view broad, but each with tapered apex, each with one apical and one subapical seta of different lengths.

Female. Unknown.

Distribution. Okinawa Island (Ryūkyū Archipelago, southwestern Japan) ( Fig. 6 ).

Etymology. This species is dedicated to Żaneta Zaborowska, my life partner, who shares my fascination with Japan and accompanied me on the Okinawan trip, although not necessarily enjoying a holiday sifting experience.

Remarks. Males of the previously described P. ishigakiana and P. inexpectata have the angulate expansion of protibiae distinctly near the proximal third; all remaining Japanese species, including P. zanetae , have a similar modification near middle of each protibia. Paraneseuthia zanetae is unique in having a very dark body (all other Japanese species are distinctly lighter); also its aedeagus strongly differs from male copulatory organs of all other congeners. Although the shape and general structure of the median lobe are similar to those of all other Japanese and Russian Far Eastern Paraneseuthia , the strongly asymmetrical and irregularly shaped endophallic sclerites are not known in any other species.

Figures

FIGURE 6. Distribution of Far Eastern nominal species of Paraneseuthia.

FIGURES 1–5. Paraneseuthia zanetae sp. n. Dorsal habitus of holotype male (1); aedeagus in ventral (2, 4) and lateral (3, 5) views.