Actinotia polyodon, the purple cloud, is a moth of the family Noctuidae.

It is found in much of the Palearctic realm, from Europe to Russia and Japan.

Forewing bone-colour suffused with olive brown along costa and inner margin and interrupted along termen; the reniform stigma also placed on an olive brown cloud: costa and space between veins 2 and 4 tinged with purplish pink; a black streak from base in submedian fold and a double one from inner margin near base; reniform stigma large, pale olive with linear centre and outline creamy white; veins towards margin dark, forming centre of wedgeshaped marks, 3, 4 and 7, 8 broadly edged with ground colour and cutting the dark fringe; outer line marked by dark dots on veins: hindwing bone-colour with broad brownish margin and blackish veins.

- Larva red-brown, dotted with black; a subdorsal row of oblique brown marks; dorsal and spiracular lines yellow; head brown.

The larvae feed on perforate St John's-wort (Hypericum perforatum) and liquorice milkvetch (Astragalus glycyphyllos).