Geometridae

70.203 Orange Underwing Archiearis parthenias (Linnaeus, 1761)

Local

Similar species: The male Light Orange Underwing Archiearis notha has slightly feathered antennae rather than serrated. The female Light Orange Underwing is much greyer than the male, whereas the female Orange Underwing is similar to the male.

Forewing: 16 to 19mm

Habitats: Open woodland and larger stands of birch on heathland.

Habits: The moth normally flies around the tree tops in sunshine, then rests during periods of cloud. As the afternoon passes it gradually flies lower. Then in the late afternoon it can be found drinking on muddy paths.

Foodplant: The nocturnal larva feeds at first on the catkins then later the leaves of Silver Birch, Downy Birch and occasionally Rowan. It rests between spun leaves during the day. It pupates in a cocoon spun into the surface of soft bark or rotten wood.