61.006 Satyrium w-album (White-letter Hairstreak)
ws: 26-36mm; late Jun – early Aug; elms (Ulmus spp); local in England and Wales.
ID: ‘W’ shaped white cross-line on hindwing underside is also seen in S.pruni (Black Hairstreak), though the ‘W’ shape is less complete in the latter. S.w-album has subterminal orange band extending from the apex and fading out halfway towards the tornus; within this band the first three interneural spaces contain a black terminal spot or crescent. In S.pruni the orange band extends to the dorsum; all the interneural spaces have a black terminal crescent and there is an additional row of black spots at the proximal margin of the orange band.
Page published 17/07/2014 (§1-4)