Anadasmus vacans is a moth of the Depressariidae family. It is found in French Guiana. The wingspan is 38-40 mm. The forewings are light greyish-ochreous, usually with irregularly scattered black specks. The plical and second discal stigmata are minute and blackish, sometimes with a curved subterminal series of minute blackish dots. There is a terminal series of minute blackish dots. The hindwings are dark grey, with the apex more or less tinged with pale ochreous.