Plateros gerstmeieri Kazantsev, sp.n.

Figs 192–194.

MATERIAL: Holotype, ♂, N Vietnam, Ninh Binh pr., Cuc Phuong N.P., lake Mac, 20°15´30´´N, 105°42´29´´E, 160 m, LFF, 6.V.2017, R. Gerstmeier leg. (NME).

DESCRIPTION. Male. Light to dark brown; pronotum light brown with testaceous margins (Fig. 192).

Vertex with broad shallow round impression behind antennal prominence and a pair of small approximate round pits at its bottom. Eyes large, interocular distance ca. 1.3 times shorter than eye diameter. Labrum small, transverse, concave anteriorly. Palps slender; ultimate palpomeres longer than wide, narrow and almost parallel-sided, obliquely convex and flattened at apex. Antennal sockets separated by minute lamina. Antennae relatively long, attaining to elytral three fifths, antennomeres 3–10 rather broad, strongly dentate; antennomere 3 ca. 2.4 times longer than antennomere 2 and ca. 1.1 times shorter than antennomere 4; antennomeres 3–11 with moderately long sub-erect pubescence (Fig. 192).

Pronotum transverse, ca. 1.3 times wider than long, with noticeably concave sides and almost as wide at anterior angles as basally, slightly bisinuate basally and semi-circularly produced anteriorly, with short acute posterior and rounded blunt anterior angles. Scutellum transverse, parallel-sided, truncate at apex (Fig. 192).

Elytra long, ca. 3.1 times longer than wide at humeri, almost parallel-sided; with four almost equally developed primary costae, not much stouter than secondary ones; interstices with even rows of small subquadrate cells; pubescence dense, short and decumbent, almost obscuring reticulation (Fig. 192).

Legs slender; femoris and tibiae relatively broad, subequal in length (Fig. 192).

Aedeagus asymmetrical, with narrow phallobase and absent sutures of phallobasal lateral plates; median lobe narrow, bent in distal half, constricted before and conspicuously widened at apex (Figs 193–194).

Female. Unknown.

Length: 4.7 mm. Width (humerally): 1.2 mm.

ETYMOLOGY. The new species is named after Dr. Roland Gerstmeier (Munich) who collected the type specimen.

DIAGNOSIS. Plateros gerstmeieri sp.n. may be separated from P. planatus Waterhouse, 1879, of similar coloration pattern and antennal structure, by the somewhat widening anteriorly pronotum with vestiges a median cell almost reaching anterior margin and noticeable transverse costae (Fig. 192), as well as by the constricted before and conspicuously widened at apex median lobe of the aedeagus (Figs 193–194).

DISTRIBUTION. Northern Vietnam, Cuc Phuong National Park.