Lasinus yamamotoi, 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 : 33-35

Lasinus yamamotoi sp. n. Figs 14, 24

Type material.

(4 ♂♂, 1♀).HOLOTYPE, ♂, labelled as follows: (p) [Japan, Ehime, Nomura Dam, Nomura-cho, 27.V.1994, M. Sakai leg.] red label (p) HOLOTYPE Lasinus yamamotoi sp. n., Bekchiev, Hlaváč & Nomura det., 2013. (NSMT). PARATYPES: (2 ♂♂, 1♀); (1 ♂) same data with holotype; (1 ♀) same data with holotype but in 23.VII.1994; (1 ♂) Japan, Shikoku, Ehime Pref., Uchiko-chô, Shiromawari, 9.VII.1995, E. Yamamoto leg. (NSMT, PCPH, NMNH).

Description.

Body unicoloured, head, pronotum and abdomen reddish-brown, elytra slightly lighter, maxillary palpi yellow, length 2.85-2.95 mm.

Head elongate, 1.08 times longer than wide and as long as pronotum; median sulcus visible on rostrum, relatively shallow at level of vertexal foveae. Genae with weak protuberance, covered with erected, dense golden setae.

Antennae (Fig. 14) about 2.02 mm long; scapes long, about 2.85 times longer than pedicels; pedicels short, 1.42 times shorter than each of antennomeres III–IV; antennomeres V and VI of same length; antennomeres VII 1.22 times longer than wide; VIII longer than wide; XI longer than wide, simple, only slightly oblique on ventral side in male, in female unmodified; X slightly longer than wide; XI longer than wide.

Pronotum slightly longer than wide, surface evenly wrinkly, evenly rounded before lateral foveae; lateral foveae well-defined; median setose fovea small; median sulcus very thin.

Legs long and slender; protrochanters with long apical spine; profemora with short, strong spine in middle; mesotrochanters with one small (male) or two (female) spines; mesofemora with small spine at basal third.

First visible abdominal tergite (IV) very long, about four times longer than second visible tergite (V), with fine punctation in anterior part, disc glabrous, surrounded with short golden pubescence on sides; carinae short, distance between carinae 0.4 of maximal tergal width. Aedeagus (Fig. 24) 0.57 mm long; median lobe weakly narrowed apically, with large and relatively short apical lobe; endophallus with two spines and small lamella; ventral spine very big, forming large plate; dorsal spine big, curved, acute at apex; lamella small, finely dentate in apical part; parameres short and slender, reaching apical lobe, enlarged at apex.

Differential diagnosis.

Lasinus yamamotoi resembles Lasinus inexpectatus due to the unmodified antennal clubs in both sexes, but it can be distinguished from the latter by the proportion of the antennomeres VII and the shape of the aedeagus.

Etymology.

Patronimic, dedicated to Mr. Eiji Yamamoto (Japan).

Distribution.

Japan (Shikoku).