Description: Wingspan 34-38mm. Adult males are generally a light greyish brown with a well-defined central band, which is normally dark brown. The wings appear long and narrow when at rest. The spider-like females are wingless and remain on the tree trunks. Mid-February to mid-April.

Irish Distribution: Widespread and fairly common, especially in the east, where it is known from many of the fens and bogs in the Lough Neagh basin. Its apparent scarcity in the west may be due to lack of recording during its early flight period.

Ecology: Recorded from a wide variety of habitats. Occasionally found at rest by day on tree trunks. Males are attracted to light in moderate numbers. The larvae feed from May to June on a wide variety of deciduous trees including oak Quercus spp., birch Betula spp. and Hawthorn Crataegus monogyna. It overwinters as a pupa.

Key Identification Features:

• Early flight period
• Females wingless
• Males rest with wings folded
• Forewings long with dark brown central band

Distribution Map from NBN: Alsophila aescularia at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Alsophila aescularia at iNaturalist World Species Observations database.