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East Midlands Branch Butterfly Conservation

Brown Argus Aricia agestis


The Brown Argus was traditionally associated with calcareous grasslands, and the loss of this habitat to agricultural improvement in southern and central England led to the butterfly's rapid decline until the 1990s when it began a dramatic expansion of its range, particularly in the north and east. It has colonised roadside verges, disused railway lines and rough land created by set-aside. It is also found in coastal dunes and heathland.


The Brown Argus is brown with prominent orange spots on the upper wings which extend to the wing tips on females. It can be confused with a number of other butterflies: it resembles the female Common Blue, but is noticeably smaller and lacks all traces of blue near the base of the wings. The undersides differ in that the The Brown Argus has almost vertical twin spots on the top edge of the hindwing, and has no cell spot on the forewing. It can also be confused with female Chalkhill Blue and Adonis Blue, but they are both much larger. It has a characteristic silvery appearance in flight.

Flight times

Throughout most of its range it is double brooded, flying from early May to the end of June and mid-July to mid-September, but in Derbyshire it is usually single brooded and on the wing during June and July.

Food plants

Eggs are laid singly on the under-surface leaves of Common Rock-rose on calcareous soils, elsewhere it favours Common Stork's-bill and various crane's-bills.

Brown Argus - © Simon Jenkins cut out picture of brown argus butterfly

Distribution Maps for the East Midlands Region

Brown Argos distribution map 2010
2010 Summary
No of tetrads 88
First sighting 01/05/2010
Last sighting 11/10/2010
Brown Argos distribution map 2011
2011 Summary
No of tetrads 87
First sighting 22/04/2011
Last sighting 04/10/2011
Brown Argos distribution map 2012
2012 Summary
No of tetrads 48
First sighting 21/05/2012
Last sighting 21/09/2012
Brown Argos distribution map 2013
2013 Summary
No of tetrads 72
First sighting 25/05/2013
Last sighting 17/10/2013
Brown Argos distribution map 2014
2014 Summary
No of tetrads 123
First sighting 14/05/2014
Last sighting 01/10/2014
Brown Argos distribution map 2015
2015 Summary
No of tetrads 109
First sighting 04/05/2015
Last sighting 29/09/2015
Brown Argos distribution map 2005-09

Combined records for the five year period 2005-09

Brown Argos distribution map 2010-14

Combined records for the five year period 2010-14

Comparison of years 2005-09 & 2010-14

No Data


Photo Gallery

Brown Argos

Brown Argus © Simon Jenkins

Brown Argos

Brown Argus © Simon Jenkins

Brown Argos

Brown Argus © Simon Jenkins

Brown Argos

Brown Argus © Simon Jenkins

Brown Argus Brown Argus Brown Argus Brown Argus
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