Lasinus okinawanus, Bekchiev, Rostislav, Hlavac, Peter & Nomura, Shuhei, 2013

Bekchiev, Rostislav, Hlavac, Peter & Nomura, Shuhei, 2013, A taxonomic revision of Tyrini of the Oriental region. V. Revision of the genus Lasinus Sharp, 1874 (Coleoptera, Staphylinidae, Pselaphinae), ZooKeys 340, pp. 21-42 : 39-40

Lasinus okinawanus sp. n. Fig. 19, 29

Type material.

(4 ♂♂, 4 ♀♀). HOLOTYPE, ♂, labelled as follows: (p) [Japan, Ryukyus, Okinawa Is., Okinawajima, Mt. Oppadake, Nakijin-son, 26.VI.1998, S. Nomura leg.], red label (p) HOLOTYPE Lasinus okinawanus sp. n., Bekchiev, Hlaváč & Nomura det., 2013 (NSMT). PARATYPES: (2 ♂♂, 3 ♀♀) same data as holotype; (1 ♂, 1 ♀) Japan, Ryukyus, Okinawa Pref., Nago-shi, Mt. Nagodake., 2.IX.2006, S. Nomura leg. (NSMT, PCPH, NMNH).

Description.

Body unicoloured, light reddish-brown, maxillary palpi yellow, length 3.0-3.2 mm.

Head elongate, about 1.03 longer than wide, and as long as pronotum; median sulcus visible on rostrum, on vertex reaching level of vertexal foveae. Genae with weak protuberance, covered with erected, dense golden setae.

Antennae long about 1.94 mm (Fig. 19); scapes 1.16 times longer than wide, 1.40 times as long as pedicels; pedicels as long as wide and as long as antennomeres III; antennomeres IV 1.25 times shorter than III; antennomeres V 1.20 times longer than wide; antennomeres VI 1.60 times longer than wide; antennomeres VII as long as wide; antennomeres VIII about 1.40 times longer and distinctly wider than VII; antennomeres IX as long as wide and about same length as terminal antennomeres, in male with large, shallow, in apical half highly inclined discoidal plate, in female unmodified; antennomeres X quadrate; terminal antennomeres 1.60 times as long as X and about 1.37 times longer than wide.

Pronotum about as wide as long, wrinkly, with weak lateral swellings before lateral foveae; lateral and median setose foveae well-defined; median longitudinal sulcus present.

Legs long and slender; protrochanters with large apical spine; profemora with longer spine in middle of its length; mesotrochanters at apex with one (male) or three (female) spines; mesofemora with minuscule spine at basal third.

Abdomen slightly wider than elytra, first visible abdominal tergite (IV) finely punctate with sparse, short golden setae; carinae short, distance between them 0.39 of maximal tergal width. Aedeagus (Fig. 29) 0.60 mm long; median lobe weakly narrowed apically, with long and narrow apical lobe; endophallus with two spines and two lamellas; ventral spine very large, short, curved downwards in middle, acute rightward at apex; dorsal spine very strong, acute at apex; dorsal lamella small finely dentate on apical part; ventral lamella large; parameres long and slender, different in length, left one overlapping apical lobe, right one shorter,.

Differential diagnosis.

Lasinus okinawanus is most closely related to Lasinus spinosus by the antennomeres IX with a shallow cavity, and the lack of an apical nail-shaped protuberance. It differs from latter by antennomeres IX having highly inclined shallow discoidal plate in apical half, and by the shape of the aedeagus.

Etymology.

The specific name is associated with the name of the type locality, Okinawa Island, where the type specimens were found.

Distribution.

Japan (Okinawajima Island).