(Figs 12–13)
Gonioctena (Brachyphytodecta) flavipennis (partim): YANG et al. (2014): 374 (taxonomy, misidentification).
Gonioctena (Brachyphytodecta) medvedevi Cho & Borowiec, 2016a: 177 (original description).
Type locality. Vietnam, Vinh Phuc Province, Tam Dao.
Type material examined. HOLOTYPE: ♂, ‘ Vietnam, Prov.Vinh-phu (divided into Vinh Phuc and Phu Tho), Tam-dao, L. Medvedev @ Dang Dap // on Ormosia (Fab.) // HOLOTYPUS Gonioctena (Brachy.) medvedevi sp. n. Cho & Borowiec 2014’ (LMCM). PARATYPES: 1 ♂ 1 ♀, same data as holotype plus ‘PARATYPUS Gonioctena (Brachy.) medvedevi sp. n. Cho & Borowiec 2014’ (LMCM); 1 ♂, same data as preceding paratype (TLMF); 1 ♂, ‘ Vietnam, TamDao, 900 m, 4.VI.1987, L. Medvedev et al. // PARATYPUS Gonioctena (Brachy.) medvedevi sp. n. Cho & Borowiec 2014’ (LMCM).
Description. See CHO & BOROWIEC (2016a).
Differential diagnosis. Gonioctena (B.) medvedevi is very similar to G. (B.) longshengensis sp. nov. and G. (B.) mauroi in body shape, coloration and setose aedeagus. From these two species, G. (B.) medvedevi can be distinguished only by aedeagus moderately narrowed with apical process moderately widened to lateral tooth-like projections near apex (subparallelsided with apical process broad, widest in apical 1/3 and subequal to median lobe in width in G. (B.) longshengensis sp. nov. and subparallel-sided with apical process widest in middle and slightly narrower than median lobe in G. (B.) mauroi). Gonioctena (B.) kuatunensis sp. nov. differs in semicircular apex of aedeagus (triangular or subtriangular in other species).
Distribution. Vietnam: Vinh Phuc Province (Fig. 13).
Remarks. The male genitalia of Gonioctena (B.) flavipennis (Jacoby, 1888) illustrated by YANG et al. (2014) without any doubts refer to G. (B.) medvedevi. The correct drawings of male genitalia of G. (B.) flavipennis were provided by CHO & BOROWIEC (2016a).