Alsophila japonensis (Warren)

(Figs 17, 18)

Alsophila japonensis: Beljaev & Mironov 2019: 252 (Sakhalin).

Material examined. S Kholmsk: 1 ♂, 19.X.2016, 5 ♂, 16, 23, 24.X.2017, 1 ♂, 21.X.2018, 2 ♂, 13, 24.X.2021; Kholmsk, downtown area: 2 ♂, 18.X.2018, 1 ♀, 30.X.2020, 1 ♀, 24.X.2022.

Distribution. Russia (S RFE: SW Sakhalin; S Khabarovskii Krai, Primorskii Krai), Japan (Hokkaido, Honshu, Shikoku, Kyushu, Tsushima, Yakushima), South Korea, China (NE, Central: Jiangsu (iNaturalist 2022b)).

Remarks. The finding of A. japonensis in Sakhalin significantly expands its distribution range to the northeast. The collected specimens belong to the nominative Japanese subspecies A. japonensi japonensis, which differs from a continental subspecies A. japonensis murinaria Beljaev in the wing pattern of forewing by a more prominent projection outward from the postmedial line along the veins M1 and M2.

The larvae are polyphagous on deciduous trees. In Sakhalin the moths fly in the second half of October. Since the first finding in Kholmsk in 1916, an increase in the number of the species has been observed.