Sphingulus mus Staudinger, 1887, in Romanoff (ed.), Mém. Lépid. 3: 156. Type locality: [Russia, Primorskiy Kray,] Suifun [Suifen river].
Synonym. Sphingulus mus taishanis Mell, 1937, Dt. ent. Z., Berl. 1937: 8. Type locality: China, Shantung [Shandong], Taishan [Tai Shan], 1550m.
Wingspan: 57--60mm. Forewing upperside with only the two most distal lines indicated, the post-discal line by double dots at the veins. Body very uniform in colour.
In the male genitalia, uncus about three times as long as basally broad, narrowed towards apex, which is truncate-sinuate with projecting angles; covered dorsally with long hair-scales. Gnathos with a rounded mesial lobe that is about as long as broad; the sides slightly incurved. Valve with inner surface covered with long, weak hair-scales. Harpe reaching beyond apex of valve, the ventro-distal process gradually narrowed, somewhat curved inward distally, not sharply pointed; a dorsal process present near the base is also obtuse. Aedeagus with a patch of spines internally, visible externally as brown dots; hook pointed. In the female genitalia, ostial plate strongly sclerotised; the lobe anterior to the ostial cavity sinuate.
In the Russian Far East, a lowland species of deciduous woodland dominated by Quercus mongolica (Izerskiy, 1999b).
China: v (Shanxi); 10-13.v (Beijing); 8-30.vi (Nei Mongol; Beijing); vii (Beijing; Heilongjiang); 28.vi-11.vii (Hubei); 4.viii (Shandong). Russia: vi (Khabarovsk); vi (Primorskiy Kray); 19.vi-viii (Primorskiy Kray); 16.vii (Primorskiy Kray); 17.vii (Amurskaya).
In northern China, Yang (1978) states that S. mus has only one generation per year during May and June; however, captures from northeastern China and the Russian Far East indicate a partial second brood during July and August in some years.
Park et al. (1999) give June-July as the flight period in Korea.
Larval hostplants. In Amurskaya, Russia, recorded from Syringa reticulata subsp. amurensis (Streltzov, Osipov & Malikova, 2003). Reared on Fraxinus in captivity (Izerskiy, 1999b). Recorded from Syringa oblata around Beijing, China (Tuozhan Fang, pers. comm. 2018).
China: Nei Mongol (Zalantun/Butha Qi; Hulunbuir Region, Sanhaodian); Heilongjiang (Harbin; Lalin); Liaoning (Changhai, Dachangshan Island); Beijing (Fangshan; Baihua Shan; Badaling National Forest Park); Shandong (Tai Shan, 1550m); Shanxi (Taiyue Shan); Shaanxi; Henan; Zhejiang; Hubei (Shennongjia; Zigui, 300m); Hunan.
Known already from northeastern China, the records from the Taiyue Shan, Shanxi and Hubei (AAUH, SIES, IZAS) represent a considerable southwestward extension of the known range of S. mus.
North Korea: North Hamgyong Prov. (Charyung; Gyungsung).
South Korea: Kyonggi Prov. (Gwangleung); Kangwon Prov. (Gwangduk-san; Seolak-san; Woljeong Temple; Jeombong-san); South Kyongsang Prov. (Hamyang).
Russia: Amurskaya (Kundur); Yevreyskaya (Obluch'e; Bastak); Khabarovskiy Kray (Khabarovsk); Primorskiy Kray (Kaymanovka; Primorskiy; Barabash; Khasan; Jankowski Peninsula; Suifen River; Vladivostok; Ussuriysk; Gribnoye; Novovladimirovka; Anuchino; Primor'e; near Kalinovka; near Lazarevka; near Zanadvorovka).
Southeastern Russian Far East and the Korean Peninsula south into eastern China.
Holarctic; eastern Palaearctic region. Pleistocene refuge: Monocentric -- Manchurian refuge.