Ypsolopha horridella (Treitschke, 1835)

(Figs 21, 72, 121)

Harpipteryx horridella Treitschke, 1835: 191; Duponchel, 1838: 292.

Theristis horridella (Treitschke): Stainton, 1854: 72; Herrich-Schäffer, 1855: 148; Frey, 1856: 75.

Cerostoma horridella (Treitschke): Heinemann, 1870: 125; Snellen, 1882: 547; Meyrick, 1895: 699.

Theristis falcella Stephens, 1834: 335 .

Harpipteryx falcella (Stephens): Wood, 1839: f. 1532.

Ypsolopha horridella (Treitschke): Coenen, 1995: 55; Agassiz, 1996: 93; Huisman et al., 2001: 178; Knill-Jones, 2002: 44; Baraniak & Vives, 2005: 324; Beltran, 2005: 442; Sohn et al, 2010: 32; Gershenson & Kozhevnikova, 2013: 104.

Type locality: Germany.

Adult (Fig. 21): Wing expanse 17.0−21.0 mm. Forewing with R4 and R5 separated (Fig. 72).

Material examined. 1 ♂, Mt. Xinglong, Yuzhong County (35°53′ N, 104°06′ E), Gansu Province, 2178 m, 20.viii.2007, coll. Feng Yang & Hanguang Gao; 4 ♂♂, Donglushanling, Horinger County (40°23′ N, 111°48′ E), Inner Mongolia Autonomous Region, 1400−1480 m, 12−13.viii.2007, coll. Houhun Li et al.; 5 ♂♂, Suyukou, Mt. Helan (38°30′ N, 106°06′ E), Ningxia Hui Autonomous Region, 2000 m, 2−17.viii.2006, coll. Feng Yang, Qi He et al.

Host plants. Rosaceae: Malus Mill., Ptunus spinosa Linn. (Agassiz 1996; Kozhevnikova 2005).

Distribution. China (Gansu, Inner Mongolia, Ningxia, Shanxi), Russia, Asia Minor, Europe.

Diagnosis. This species is similar to Y. yangi Ponomarenko et Sohn superficially, but differs in the forewing triangularly protruded at the apex (Fig. 21) and the separated R4 and R5 (Fig. 72); in Y. yangi, the forewing is rounded at the apex (Fig. 20), and R4 is stalked with R 5 in the forewing (Fig. 71). Ypsolopha horridella is related to Y. scabrella (Linnaeus) in the male genitalia, but differs in the saccus about 3/4 length of the socius and truncate at apex (Fig. 121), which is as long as the socius and sharp at apex in the latter species (Fig. 118).

Remarks. Caradja (1939) recorded this species from China based on the specimens collected in Mt. Mian, Shanxi Province. Sohn et al. (2010) assumed it a misidentification since it is not listed in Hua’s checklist (2005). We confirm its existence in China based on the previous literature and the specimens in our collection.