Orthosia opima (Hubner, 1809)

Description: Wingspan 34-40 mm. Forewings are greyish brown with a central band which is broader towards the costa. Crosslines are poorly defined. The subterminal line is straight and dark and edged with white. Hindwings are greyish brown with a small lunule.

Key Identification Features:

• Grey forewings with central band
• Straight subterminal line
• Greyish brown hindwings with small discal lunule

Sets:

Flight Period: Not known in N. Ireland. Skinner gives mid-April to mid-May as the normal flight period in Britain.

Status: Unknown as there are no recent records of this heathland species. Baynes describes it as being widely distributed but uncommon. There are old records from Antrim, Tyrone, Down and Armagh. This species has been targeted in recent fieldwork at some of its former haunts and at other potentially suitable areas around the Lough Neagh basin without any success.

Ecology: A spring species associated mainly with heaths, dunes, fens, and bogs. Adults are attracted to light and will also visit willow Salix spp. catkins and Blackthorn Prunus spinosa blossom. The larvae feed during May and June on willow Salix spp., birch Betula spp. and Ragwort Senecio jacobaea. It overwinters as a pupa.

World Distribution: Northern Europe from southern Norway to northern France.

Bradley & Fletcher number: 2184 Agassiz number: 73.248

Additional information:

UK Moths account

Caterpillar: