Female Clouded Yellow , but which ?

[Greenie]

Whilst doing the transect at High Elms LNR near Bromley this morning , the second butterfly recorded was what looked at a distance like a damaged White , but on getting closer it became obvious that it was a Clouded Yellow . Obviously a female , but which one ? I haven't come across such a specimen before , so would be grateful for any assistance .
The full transect produced 15 species , including a pristine 2nd. brood Dingy Skipper .

[Neil Hulme]

Hi Greenie,
That's a Clouded Yellow helice form.
BWs, Neil

[Greenie]

Neil ,
Thanks very much for the ID . That's a first for me .

[David M]

Nice work, Greenie. Good sighting.