Plateros tamdaoensis Kazantsev, sp.n. Figs 38, 129–130. MATERIAL: Holotype, ♂, [N] Vietnam, Vinh-Phu prov., Tam Dao, Dang Dap, secondary mountain rainforest, 11–13.V.1975, L. Medvedev leg. (ICM); paratype, ♀, [N] Vietnam, mountains near Tam Dao, 900 m, 9.VI.1963, O. Kabakov leg. (ICM). DESCRIPTION. Male. Dark brown to black; pronotal margins and humeri narrowly testaceous (Fig. 38). Vertex with conspicuous broad round impression behind antennal prominence. Eyes relatively small, interocular distance ca. 1.1 times greater than eye diameter. Labrum small, transverse, almost truncate anteriorly. Palps slender; ultimate palpomeres narrow, almost parallel-sided in proximal two thirds, obliquely truncate and flattened at apex. Antennal sockets separated by minute lamina. Antennae attaining to elytral two thirds, antennomeres 3–10 flattened, feebly dentate; antennomere 3 ca. 2.6 times longer than antennomere 2 and ca. 1.4 times shorter than antennomere 4; antennomeres 3–11 with dense short sub-erect pubescence and much longer separate bristles (Fig. 38). Pronotum transverse, ca. 1.4 times wider than long, trapezoidal, moderately bisinuate basally and somewhat triangularly produced anteriorly, with minute acute, protruding laterally posterior and conspicuous blunt anterior angles; disk smooth. Scutellum subquadrate, parallel-sided, triangularly incised at apex (Fig. 38). Elytra relatively broad, ca. 3 times longer than wide at humeri, parallel-sided; with four almost equally developed primary costae, not significantly different from secondary ones; interstices with even rows of small roundish cells; pubescence relatively scarce, short and decumbent (Fig. 38). Legs relatively robust; femoris wide, femoris and tibiae subequal in length (Fig. 38). Aedeagus asymmetrical, relatively slender, with moderately narrow phallobase and obsolete phallobasal lateral plates; median lobe narrow, straight proximally, abruptly bent in distal third, with small tooth at distal bend (Figs 129–130). Female. Similar to male, but eyes somewhat smaller. Length: 6.0– 6.8 mm. Width (humerally): 1.6–1.9 mm. ETYMOLOGY. The new species is derived from the locality where the type series was collected. DIAGNOSIS. Plateros tamdaoensis sp.n. may be distinguished from the somewhat similar in the structure of the aedeagus P. chinensis by the longer antennae and mostly dark brown pronotum (Fig. 38), as well as by the slenderer median lobe of the aedeagus with longer proximal straight portion, shorter and more abruptly bent distal third and small tooth at distal bend (Figs 129–130). DISTRIBUTION. Northern Vietnam.

Published as part of Kazantsev, S. V., 2021, A review of Plateros Bourgeois, 1879 of Indochina (Coleoptera: Lycidae), pp. 47-73 in Russian Entomological Journal 30 (1) on pages 71-72, DOI: 10.15298/rusentj.30.1.07, http://zenodo.org/record/10978325