Myllaena japonica Sharp, 1888

Liu, Tian-Tian, Nozaki, Tsubasa, Yamamoto, Shûhei & Maruyama, Munetoshi, 2022, Synopsis of the Japanese species of Aleocharinae (Coleoptera: Staphylinidae), with review of the type specimens II. Genus Myllaena Erichson of tribe Myllaenini with redescription of four Japanese species, Zootaxa 5091 (2), pp. 373-382 : 374-375

Myllaena japonica Sharp, 1888

[Japanese name: Migiwa-hanekakushi]

(Figs. 1, 5–8, 18)

Myllaena japonica Sharp, 1888: 377 (original description; type locality: Japan, “Miyanoshita” [Hakone-machi, Kanagawa-ken, eastern Honshû]); Bernhauer & Scheerpeltz 1926: 507 (catalogue); Li 1992: 55 (record from China); Paśnik 2001: 189 (record from North Korea); Smetana 2004: 465 (catalogue); Schülke & Smetana 2015: 678 (catalogue).

Type material. Lectotype, here designated, ♂, “Type [RRL]// Myllaena japonica Type/D.S./Miyanoshita/ May 1880 Lewis // Miyanoshita // Japan./ G. Lewis. //Sharp Coll./1905 – 313.// Lectotype / Myllaena /japonica/ Sharp, 1874/des. Maruyama, 2011[RPC]” (considerably broken, probably by DS; abdominal segments VIII – X and aedeagus were dissected and mounted by MM) ( BMNH).

Non-type specimens examined. [ Japan]: Honshû: 6 ♂, 4 ♀, 61 unsexed, Amagi-tôge, Kawazu-chô, Shizuokaken, 16 III 1996, M. Maruyama ( KUM) ; 1 ♂, 1 ♀, 8 unsexed, same locality, 14 III 1996, M. Maruyama ( KUM) ; 2 ♂, 17 unsexed, same locality, 14–16 III 1996, S. Naomi ( KUM) .

Distribution. China (Heilongjiang, Jilin)?; North Korea?; Japan (Honshû: Kanagawa, Shizuoka; Kyûshû: Nagasaki?). See, Comments below.

Redescription. Body (Figs. 1, 5) large, robust, about 2.2–3.0 mm, widest at elytra. Color darker brown, but mouthparts, basal segments of antennae, and legs reddish brown, similarly colored, a little paler than body color.

Head subtriangular, more or less produced anteriorly, wider than length, shorter than pronotum and elytra; eyes large, almost as long as temporal length; antenna reddish brown, longer than total length from head to pronotum; antennal segments all longer than width; segment I shortest, about half shorter than II, almost 0.6 times shorter than III; XI almost as long as II, and about 2 times longer than I.

Pronotum shorter than elytra and wider than head, semicircular, trapezoid, and wider than length, and widest at base; posterior-lateral angle acute, slightly protrude posteriorly; basal width about 1.8 times wider than narrowest width.

Elytra wider than length; hind wings fully developed.

Median lobe of aedeagus (Figs. 6 – 7) rather simplified; flagellum long; basal sclerites separated; apical sclerites separated, semicircular. Spermatheca (Fig. 8) about 17 times coiled at base.

Measurements of lectotype. BL, ≈ 3.0; PL, 0.59; PW, 0.83; HTL, 0.48.

Measurements of specimens from Shizuoka. BL, 2.2–3.0; FBL, 1.4–1.5; HL, 0.30–0.45; HW, 0.48–0.55; PL, 0.55–0.61; PW, 0.85–0.90; EL, 0.68–0.80; EW, 0.93–0.95; HTL, 0.48–0.55; AL, 1.15–1.25; AS-I, 0.07–0.09; AS-II, 0.14–0.15; AS-III, 0.12–0.13; AS-XI, 0.17–0.2.

Comments. This species was recorded from China and North Korea ( Li 1992; Paśnik 2001). However, these records are doubtful because they are not based on observation of the genitalia of M. japonica , that is essential for species-level identification for this group. Re-examination of the voucher specimens is needed.

This was originally described from Nagasaki and Miyanoshita(possibly in Kanagawa).The syntype are composed of two females from Nagasaki and one male from Miyanoshita , and the latter is designated as lectotype because the specimens from Nagasaki belong to a different species (see, Comments of the next species). A distribution map of the examined specimens of this species in Japan is illustrated in Fig. 18 . In Shizuoka, this species was collected in leaf litter near a wet cliff along the old road of Amagi-tôge .

Figures

FIGURES 18 Locality map of examined specimens of Myllaena spp. from Japan: white triangle, M. japonica Sharp, 1888; black triangle, M. lewisi Cameron, 1933; white inverted triangle, M. rufotestacea Cameron, 1933; black inverted triangle, M. torrentum Cameron, 1933.