It is also of a different form (f. gallicus) having different markings to a typical specimen.
From what I know it feeds on the roots of Bracken, which there is plenty of at Sherrardspark Wood, why this moth isn't at Thorndon Country Park (the biggest space of open Bracken in the County of Essex) is beyond me! perhaps it is, perhaps we have yet to find it, who knows!
Other species of note were Brindled White-spot and Lobster Moth.
Map-winged Swift f. gallicus

Lobster Moth
Musotima nitidalis
L-album Wainscot
Feathered Ranunculus
Agonopterix nervosa
Blossom Underwing
Beautiful Marbled
Lampronia fuscatella
Gravitarmata margarotana
Perittia obscurepunctella
Black-spotted Chestnut
Cydia pactolana