Agrisius soror sp. n.

(Figs 4–6, 29, 30, 40, 48)

Type material. Holotype (Figs 4, 29): male, “Nord-Vietnam, Mt. Fan-si-pan, Cha-pa, 2400m N (22.15′N 103.46′E) 8.–29. V. 1993, leg. Sinajev [recte: Sinyaev] & Simonov” / “Genitalpräparat Heterocera Nr. 35.766 Museum Witt München” (MWM / ZSM).

Paratypes: NORTH VIETNAM: 37 specimens of both sexes with the same data as in the holotype; 163 specimens of both sexes, Mt. Fan-si-pan, Cha pa, 1700 m NN (22°15′N, 103°46′E), VI.1994, Sinyaev & local collector leg., gen. prep. No.: ZSM Arct. 2021-218 (female); 132 specimens of both sexes, the same locality as previous but 8–29. V.1993, Sinyaev & Simonov leg.; 48 specimens of both sexes, the same locality and collectors as previous but 5–29. V.1993; 4 specimens, 2350 m, Mt. Fan-si-pan (North), Cha-pa, primary cloud forest, 22°15′N, 103°45′E, 28–30.X.1994, Sinyaev & local collector leg.; 720 specimens of both sexes, 1600–1800 m, Mt. Fansi-pan (West), Cha-pa (= Sapa), sec. forest / agricult., 22°20′N, 103°40′E, 10. VI.–6.VII.1994, Sinyaev & local collector, gen. prep. No.: MWM 35.770 (male); 13 specimens of both sexes, the same locality as previous but V.1995, local collectors leg., ex coll. Schintlmeister; 81 specimens of both sexes, the same locality as previous but 30. VI.–12.VII.94, Brechlin / Schintlmeister leg., gen. prep. Nos.: MWM 33.785, MWM 33.786, MWM 35.767 (males), MWM 35.771 (female); 1 male, the same locality as previous but III.1995, V. Sinyaev leg.; 2 males, the same locality as previous but IX.1994, secondary forest, leg. Mong; 1 male, Mt. Fan-si-pan, N side, Cha-pa (= Sapa), 1600 m, 22°17′N, 103°44′E, primary forest, 28.X.–3.XI.1994, Sinyaev & local collectors leg., ex coll. A. Schintlmeister; 50 specimens of both sexes, Tam Dao, (secondary forest), 60 km NW Hanoi, 950 m, 21°34′N, 105°20′E, IV.1995, V. Sinyaev leg. (all in MWM / ZSM);

Diagnosis. The forewing length is 19.0–21.0 mm in both sexes. The new species is externally similar to A. guttivitta but is distinguished by the almost blackish fore- and hindwing cilia whereas the cilia of A. guttivitta are white with blackish spots opposite the veins. Additionally, compared to A. guttivitta, A. soror has a somewhat larger discal spot and spots of the postmedial line, and a somewhat more intense greyish-brown distal suffusion on the veins of both wings. The male genital capsule of A. soror is similar to A. guttivitta but differs in the basally thinner branches of the uncus, the longer dorsal process of the sacculus and the somewhat slenderer ventral process of the sacculus. The phalli of the two species are very similar but the distal diverticulum of the vesica of A. soror is somewhat longer than in A. guttivitta. In the female genitalia of new species, the postvaginal plate is less concave posteriorly than in A. guttivitta. The antrums of the two species are similarly gelatinous, but that of A. soror is longer and anteriorly broader (in proportion to the ovipositor width) than in its congener, with somewhat broader postero-lateral processes, and bearing three heavily sclerotised plates with crests posteriorly and a weakly sclerotised plate laterally, whereas the antrum of A. guttivitta bears only two heavily sclerotised plates with thorns laterally. Additionally, the posterior (the narrowest) section of the ductus bursae of A. soror is markedly shorter than in A. guttivitta.

Distribution. Known only from North Vietnam (Lào Cai Province).

Etymology. In Latin, ‘soror’ means ‘a sister’. The specific epithet refers to the new species’ close affinity to A. guttivitta.