Tetraserica thainguyensis sp. n. Figures 5, 53

Type material examined.

Holotype: ♂ "N. Vietnam: 40 km NE Thainguyen, 300 m, 8.V.1963, leg. O. Kabakov/ 1009 Asia Sericini spec." (ZIN).

Description.

Length of body: 7.6 mm; length of elytra: 7.1 mm; maximum width: 6.3 mm. Surface of labroclypeus and disc of frons glabrous. Smooth area anterior to eye twice as wide as long. Eyes moderately large, ratio of diameter/interocular width: 0.56. Ratio of length of metepisternum/metacoxa: 1/1.74. Metatibia short and wide, ratio width/length: 1/2.32; basal group of dorsal spines of metatibia at first third of metatibial length.

Aedeagus: Fig. 5 E–H . Habitus: Fig. 5I.

Female unknown.

Diagnosis.

Tetraserica thainguyensis sp. n. differs from the similar T. geiserae by having the left paramere very short and split into two lobes.

Etymology.

The new species is named with reference to its occurrence close to Thainguyen (adjective in the nominative singular).