High Brown Fritillary (Argynnis adippe)
Species

Male. Taken at Arnside Knott, Lancs, on July 3rd 2016.
(1/3200th sec at f13. Approx 1.7x lifesize.)

Male underside. Taken at Gait Barrows NNR, Lancs, on July 31st 2014.
(1/400th sec at f11. Approx 1.7x lifesize.)

© David Hastings

Description

Wing span: 55 - 69 mm
 
This butterfly is easily mistaken for a Dark Green Fritillary and the two often fly together, making a positive identification difficult. The two species are most easily distinguished by their undersides; the High Brown Fritillary has a row of brown spots between the outer margin and the silver spangles, which are missing in the Dark Green Fritillary.
 
In the UK this butterfly is confined to the Morecambe Bay area of north-west England, North Devon, South Devon (including Dartmoor), Exmoor in South Somerset, and a few sites in Wales. It is widespread and common in most of Europe.
 
The High Brown Fritillary requires open coppiced woodland. It soon disappears if a site become too overgrown. It can also be found on limestone pavement, where violets grow in the grykes.
 
In England, adults emerge in the second half of June on southern sites, peaking in early July, but may not appear until early July further north, peaking a little later in mid-July. There is a single generation each year. The ovum is the over-wintering stage.
 
The primary larval foodplants are Common Dog-violet (Viola riviniana) and Hairy Violet (Viola hirta). Adults feed primarily on Thistles (Cirsium spp. and Carduus spp.). Betony (Stachys officinalis), Bramble (Rubus fruticosus), Knapweeds (Centaurea spp.) and Thyme (Thymus polytrichus) are also used.
 
Both sexes are powerful flyers. Males will patrol wide areas of habitat when looking for a mate, and will investigate any brown object that might be a virgin female.
 
This species is listed as Critically endangered in the latest Red List of British Butterflies (PDF).
 

Sightings

03-Jul-2016:Arnside Knott, Cumbria(5)
31-Jul-2014:Gait Barrows NNR, Lancashire(3)
30-Jul-2014:Arnside Knott, Cumbria(2)