71.018 Pheosia gnoma (Lesser Swallow Prominent)
fw: 20-26mm (W&T), ws: 46-58mm (MBGBI9); bivoltine Apr-Jun, Jul-Aug; silver/downy birch (Betula pendula/pubescens); common throughout GB
Pheosia gnoma (Lesser Swallow Prominent) §1 male
ID: very similar to P.tremula (Swallow Prominent). These two can be distinguished by a narrow white wedge that extends along the dorsum from the tornus. In P.gnoma this wedge is distinct and short, extending less than halfway to wing-base; in P.tremula it is less distinct and longer, extending at least halfway to wing base. In the hindwing both species show a dark brown tornal spot: in P.tremula this spot is small and intersected by a white marginal line; in P.gnoma it is diffuse and not intersected.
§1 Anglesey; 01/08/2007; male
§2 Eskdale, CUmbria; 20/08/2007; male
§3 Strumpshaw Fen, Norfolk; 14/05/2015
§4 Foulden Common, Norfolk; 11/04/2016; male; fw 21.6mm; to light
§5 Orlestone Forest, Kent; 16/08/2023; female; fw 23.5mm
All images © Chris Lewis
§2 Eskdale, CUmbria; 20/08/2007; male
§3 Strumpshaw Fen, Norfolk; 14/05/2015
§4 Foulden Common, Norfolk; 11/04/2016; male; fw 21.6mm; to light
§5 Orlestone Forest, Kent; 16/08/2023; female; fw 23.5mm
All images © Chris Lewis
Page published 19/12/2014 (§1-2) | §3 added 01/04/2015 | §4 added 15/02/2017 | §5 added 22/12/2023
