Chalybion japonicum (Gribodo, 1882) (Fig. 14)

Material examined: VIETNAM: Hoa Binh: 2 ♀♀, 2 ♂♂, Yen Thuy, 30.iii - 10.iv.2003, Malaise trap, Long Dang Khuat; 1 ♂ , Da Phuc, Yen Thuy, 20-30.iv.2003, Malaise trap, Long Dang Khuat; 1 ♀ , Tan Son, Mai Chau, 10- 15.iv.2010, Malaise trap, Long Dang Khuat; 3 ♀♀, 10 ♂♂ , Tan Vinh, Luong Son, 2.v.2017, Phong Huy Pham . Son La: 2 ♀♀, 2 ♂♂, Chieng Bom, Thuan Chau (Copia Natural Reserve), 15.v.2017, 1010m, Phong Huy Pham; 1 ♀, 2 ♂♂ , Son La ciy, 10-20.v.2017; 2 ♀♀, Son La city, 1-10.viii.2017, Malaise trap, Long Dang Khuat .

Distribution: Vietnam: Tonkin (= northern Vietnam), Ha Giang, Hanoi (Hensen 1988), Hoa Binh, Son La. Elsewhere: China, Japan, Korea, Taiwan, Russian Far East, Thailand, Laos.

Remarks: Hensen (1988) recorded this species for Tonkin (= northern Vietnam), but he did not show the distribution at province level. Hoa Binh and Son La are provinces belonging to north Vietnam. In the present study, C. japonicum is, hence, not newly recorded for northwest Vietnam.