Nogunius aogashimanus sp. n.

(Figs 47–48, 73–76)

Type material. Holotype: JAPAN (Tokyo Pref.): ♂, two labels: “[Izu Is.] / Yasundogô / Aogashima / 24.V.1979 / J. Okuma ” [white, handwritten], “ NOGUNIUS / aogashimanus m. / HOLOTYPUS, P. JAŁOSZYŃSKI, 2020” [red, printed] (EUMJ). Paratype: 1 ♀, same data as for holotype (EUMJ).

Diagnosis. Eyes in male conspicuously large, in dorsal view as long as tempora; aedeagus in ventral view about three times as long as broad, with apical margin bearing a large median subtriangular projection.

Description. Body of male (Fig. 47) strongly convex, uniformly light brown, covered with setae distinctly lighter than cuticle; BL 0.83 mm.

Head (Fig. 48) broadest at eyes, HL 0.15 mm, HW 0.18 mm; tempora in dorsal view as long as eyes; vertex and frons confluent, together weakly convex; each eye large, strongly convex, bean-shaped, with distinct posteromedian emargination, composed of 27 facets, ommatidia are small in dorsal 1/3 of eye and becoming gradually larger toward median area, to decrease in diameter in ventral 1/3. Punctures on vertex fine, inconspicuous; setae short, sparse and suberect; tempora and posterior margin of vertex densely covered with thick bristles. Antennae slender, AnL 0.33 mm, antennomeres I and II each strongly elongate, III–VIII each about as long as broad or indistinctly transverse, IX distinctly larger than VIII, slightly transverse, X much larger than IX, strongly transverse, XI indistinctly narrower and slightly longer than X, about as long as broad.

Pronotum subconical with strongly rounded sides, broadest shortly in front of base; PL 0.23 mm, PW 0.20 mm. Anterior and posterior margins weakly convex, base with two pairs of small, distinct pits. Punctures on pronotal disc fine, inconspicuous; setae sparse, short, suberect; sides, especially posteriorly, with sparse, thick bristles.

Elytra together oval, broadest indistinctly in front of middle; EL 0.45 mm, EW 0.35 mm, EI 1.29; humeral calli weakly elevated, basal impressions large, deep, nearly circular; apices separately rounded. Punctures inconspicuous; setae slightly longer and denser than those on pronotum, suberect.

Legs moderately long and slender, unmodified.

Aedeagus (Figs 73–76) elongate, in ventral view about three times as long as broad; AeL 0.10 mm; median lobe in ventral view broadest in basal region, with nearly straight sides slightly narrowing toward truncate apex, apical margin at middle with large, subtriangular projection; parameres slender, each with one long apical and one long subapical seta.

Female similar to male, but with distinctly smaller, less convex eyes, each composed of 10 ommatidia; antennae slightly shorter in relation to body. BL 0.80 mm; HL 0.15 mm, HW 0.18 mm, AnL 0.28 mm; PL 0.23 mm, PW 0.20 mm; EL 0.43 mm, EW 0.33 mm, EI 1.31.

Distribution. Aogashima, the southernmost inhabited island of the Izu archipelago (Fig. 85).

Etymology. Named after Aogashima island.

Remarks. Nogunius aogashimanus is most similar to N. sokani; see remarks under the latter species.