Myllaena torrentum Cameron, 1933

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 : 375-379

Myllaena torrentum Cameron, 1933

[Japanese name: Ô-migiwa-hanekakushi]

(Figs. 2, 10–11, 18)

Myllaena torrentum Cameron, 1933: 172 (original description; type locality: Japan, “KOBE: Cascade Valley” [Kôbe-shi, Hyôgo-ken, western Honshû]); Smetana 2004: 465 (catalogue); Schülke & Smetana 2015: 679 (catalogue).

Type material. Holotype?, ♂, “ Type [RRL]// JAPAN / Kobe / Cascade /20.XII.27// M. torrentum / TYPE Cam.// Cameron /Bequest./B. M. 1955–147.” (abdominal segments VII–X and aedeagus were dissected and mounted by MM).

Distribution. Japan (Honshû: Hyôgo).

Redescription. Male. Body (Fig. 2) large, robust, about 2.8 mm, widest at elytra. Color brown, but mouthparts, basal segments of antennae, and legs reddish brown; pronotum and elytra similarly colored, paler than head.

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

Pronotum almost as long as longest of elytra, and wider than head, trapezoid and wider than length, widest width about 1.7 times wider than narrowest width.

Elytra wider than length; hindwings fully developed.

Median lobe of aedeagus (Figs. 10 – 11) with base of apical lobe slightly dentate in lateral view; flagellum long, thick; basal sclerites contiguous; apical sclerites connected to form crescent shape.

Female unknown.

Measurements of lectotype. BL, ≈ 2.8; PL, 0.52; PW, 0.75; HTL, 0.28.

Comments. This species was originally described from “ Cascade Valley ” of Kôbe-shi. Only a single specimen with RRL was found in BMNH and this may represent holotype though the number of the examined specimens was not specified in the original description. A distribution map of the examined specimens of this species in Japan is illustrated in Fig. 18 .

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.