Synergus formosanus Schwéger & Melika, 2015

Synergus formosanus Schwéger & Melika in Schwéger et al. (2015a) . Zootaxa 3999 (4): 469. Type material: PHMBL (holotype), paratypes in PHMBL, USNM and NCHU according to Schwéger et al. (2015a).

Material examined (7♂ & 12♀). Newly reared material deposited in UB with the following data: KOR 7: Dae- jeon, Chungnam National University campus, Ex. asexual galls of Trichagalma serratae, Q. variabilis, (15.iv.2018) 16–31.v.2018, Roca-Cusachs leg.: 3♀; KOR: 15, Jeju Island, Donbaekdonsan (South Korea), Ex. asexual galls of Trichagalma serratae, Q. variabilis, (24.v.2018) 01–16.vi.2018, Roca-Cusachs leg.: 1♂; KOR: 28 & 39, Incheon, Jung-gu, Muui-dong, Mt. 151–1 (South Korea), Ex. asexual galls of Trichagalma formosana, Q. acutissima, (18. v.2019) vi.2019, H. J. Shim leg.: 6♂ & 5♀; KOR: 30, Daejeon, Chungnam National University campus, Ex. asexual galls of Plagiotrochus kunugiphagus, Q. acutissima, (18.ix.2019), Roca-Cusachs leg.: 4♀.

Distribution. Taiwan (Nantou county) (Schwéger et al. 2015a). First record of this species for South Korea (this paper).

Biology. Reared from galls of Trichagalma formosana Melika & Tang, 2010 on Quercus variabilis (Schwéger et al. 2015a) . The new material included in this paper was reared from asexual galls of Trichagalma serratae on Q. variabilis, and from asexual galls of T. formosana and Plagiotrochus kunugiphagus on Q. acutissima .