Description: Wingspan 34-38mm. Adults have pale brown forewings with two dark median lines; the edges are scalloped or ragged and often freckled with a hook-like tip at the apex. At rest the adult closely resembles a dead birch leaf. Early May until the beginning of September. Stated to be double-brooded in Ireland (Skinner 1984), though the current data does not indicate this clearly. Adults are most frequently encountered in May and early June and again during August.

Irish Distribution: Widespread and frequently encountered especially in southern and western counties.

Ecology: A distinctive species that has a preference for damper habitats, especially where birches flourish. It occurs on heaths, bogs and fens, particularly those in the Lough Neagh basin where it is commonly encountered. Adults come frequently to light and are occasionally found during the day resting among the leaves of its foodplant. The larvae feed on birch and spend the winter months in the pupal stage protected in a cocoon.

Key Identification Features:

• Hooked tip to forewing
• Scalloped edges to forewing
• White hindwing
• Rests with wings folded over back, resembling a dead leaf

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

iNaturalist: Falcaria lacertinaria at iNaturalist World Species Observations database.