Euconnus (s. str.) uchinaanchu, Jałoszyński, 2022

Jałoszyński, Paweł, 2022, Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae), Zootaxa 5194 (3), pp. 343-391 : 357

Euconnus (s. str.) uchinaanchu sp. n.

( Figs 48–53 , 110 )

Type material studied. Holotype ( Japan : Okinawa Prefecture: Okinawa-jima Is.): ♂, two labels: “ JAPAN, OKINAWA Island / Oura Bay, Futami - Wansaka / Oura Park, 20-140 m, roadside / 10.02.2019 / leg. P. JAŁOSZYŃSKI” [white, printed], “ EUCONNUS s. str. / uchinaanchu m. / P. Jałoszyński, ’22 / HOLOTYPUS ” [red, printed] ( NSMT).

Diagnosis. Antennal club clearly trimerous and stout; head distinctly elongate, with vertex bulging posterodorsad and in males with faint, barely discernible transverse groove between supraantennal tubercles, lacking lateral impressions; pronotum nearly round, with one pair of tiny antebasal pits connected by extremely faint, barely noticeable transverse impression, and with indistinct sublateral carinae; protibiae in males unmodified, weakly and evenly curved; aedeagus weakly sclerotized, in ventral view bottle-shaped, with symmetrical pair of strongly elongate and distomesally curved endophallic sclerites in subapical region.

Description. Body of male ( Fig. 48 ) elongate, strongly convex; pigmentation moderately light brown, appendages not distinctly lighter; body covered with setae distinctly lighter than cuticle; BL 1.20 mm.

Head smaller (especially narrower) than pronotum, broadest at eyes, distinctly elongate, HL 0.30 mm, HW 0.24 mm; tempora in dorsal view over twice as long as eyes, behind eyes strongly and evenly convergent posterad, posterior margin of vertex strongly rounded, strongly bulging posterodorsad. Frons with indistinct transverse groove between supraantennal tubercles, lacking lateral impressions. Frons and vertex with unremarkable, fine punctures, glossy; setae sparse and suberect, tempora with dense but short thick bristles. Antennae short and compact, with compact and broad trimerous club, AnL 0.40 mm, scape and pedicel each elongate, antennomeres 3‒10 each transverse (3‒8 weakly, 9 and 10 strongly so), 11 slightly shorter than 9 and 10 combined, about as long as broad.

Pronotum almost round, broadest indistinctly behind middle; PL 0.30 mm, PW 0.28 mm. Base with one pair of tiny antebasal pits connected by faint transverse impression, and with indistinct sublateral carinae. Punctures and setae on disc similar to those on frons and vertex; sides of pronotum with dense thick bristles.

Elytra together oval, broadest slightly in front of middle; EL 0.60 mm, EW 0.43 mm, EI 1.41; humeral calli small but clearly marked and mesally demarcated by short elongate impressions; elytral apices separately rounded. Punctures distinct but very shallow, superficial and diffuse, unremarkable; setae sparse and only slightly longer than those on pronotal disc, only slightly suberect.

Legs slender, protibiae unmodified, weakly and evenly curved.

Aedeagus ( Figs 49–53 ) moderately elongate, bottle-shaped, weakly sclerotized, AeL 0.25 mm; median lobe in ventral view broadest in subapical region, in lateral view median lobe weakly curved, dorsal apical plate in ventral view elongate subtrapezoidal with truncate median portion; endophallus in subapical region with conspicuous symmetrical pair of elongate sclerites strongly curved distomesad ( Fig. 52 ). Parameres broad and short, not reaching apex of median lobe, each with 5 apical and subapical setae of various lengths, parameral base with small collar.

Female. Unknown.

Distribution. Japan, central Ryūkyū: Okinawa-jima Is. ( Fig. 110 ).

Etymology. The epithet uchinaanchu (noun in apposition) is borrowed from Uchinaaguchi, the language of Okinawa, and means an inhabitant of Okinawa-jima.

Remarks. This species is unique in having a pair of elongate, curved endophallic sclerites and the head in males indistinctly modified, with only a trace of shallow transverse groove between supraantennal tubercles.

Figures

FIGURE 110. Distribution of Euconnus rectitibia sp. n., E. kirin sp. n., E. yaimanus sp. n., and E. uchinaanchu sp. n.

FIGURES 48‒53. Euconnus uchinaanchu sp. n., male. Dorsal habitus (48); aedeagus in ventral (49, 51) and lateral (50, 53) views; endophallic sclerites in ventral view (52).