Erasmia pulchella is a species of moth in the burnet moth family Zygaenidae and in the subfamily Chalcosiinae. It was described by Frederick William Hope in 1840. It is found throughout Southeast Asia, with its range stretching from northern India, Myanmar, Laos, Thailand, Vietnam, China, Taiwan, and Japan. It is the type species of the genus Erasmia.

The moth's larvae feed on Helicia cochinchinensis, and they build up toxic cyanide compounds within its body. As a deterrent, the moths are brightly colored to serve as aposematic coloration. Additionally, under threat, the adult moths can exude toxins in the form of a foam that is typically exuded from the neck. The chemical compounds linamarin and lotaustralin have been isolated from the moth as specific noxious chemicals. Various subspecies exude the toxins through various locations. There are six known subspecies of Erasmia pulchella.

The moth is known as サツマニシキ, Satsuma-nishiki in Japanese, the name refers to the resemblance of the moth's wings to nishiki cloth, a type of dyed silk cloth with interwoven gold thread. The Chinese name for the moth is 山龍眼螢斑蛾, Shān lóngyǎn yíng bān é, "Mountain longan moth" and 雙星錦斑蛾, Shuāngxīng jǐn bān é, "Double star firefly moth". The former refers to its diet of Helicia cochinchinensis and the latter refers to its wing patterns.

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