Andricus hakonensis (Ashmead, 1904)

Callirhytis hakonensis Ashmead, 1904: 81, ǒ.

Andricus attractus Kovalev, 1965: 33, ǒ [syn. in Wachi & Abe (2010: 323)].

Andricus symbioticus Kovalev, 1965: 34, ǒ [syn. in Wachi & Abe (2010: 323)].

Andricus hakonensis (Ashmead) Wachi & Abe (2010: 323), ♂ ♀ & ǒ.

Distribution. China (Liaoning Province) (Pujade-Villar et al. 2019a: 41), Japan (Hokkaido, Honshu, Kyushu, Shikoku) (Ashmead 1904: 81; Monzen 1929: 355, Monzen 1931: 193; Shinji 1944: 48 and photo 75; Sakagami 1952: 74; Abe 1988a: 41–42, 1992a: 166; Katsuda & Yukawa 2004: 114; Wachi & Abe 2010: 325), Korea (Yukawa & Masuda 1996: 130, Pujade-Villar et al. 2020a: 1209), and the Russian Far East (Kovalev 1965: 34–35; Wachi & Abe 2010: 325).

Remarks. The sexual generation was described by Wachi & Abe (2010) and the two generations in the lifecycle were linked by Yukawa & Masuda (1996).

Biology. The sexual generation induces integral leaf and petiole galls, while the asexual generation induces detachable twig galls—in both cases on hosts in Quercus section oaks: Q. aliena, Q. dentata, Q. mongolica Fisch. ex Ledeb. and Q. serrata (= Q. glandulifera Blume) (Table 1; Wachi & Abe 2010; Pujade-Villar et al. 2020a).