Stenoma alligans is a moth of the Depressariidae family. It is found in the Amazon region. The wingspan is about 20 mm. The forewings are ochreous-brown, slightly crimson-tinged and with the extreme costal edge orange. There is a very slender dark brown dorsal streak from one-fourth to near the tornus. The plical and second discal stigmata are very small and fuscous. The terminal edge is slenderly suffused with ferruginous-brown. The hindwings are rather light greyish-fulvous with the dorsal half grey.