Endemic to the Balkan Peninsula. Apart from Bulgaria this mountain butterfly is only found in north-western Greece, Macedonia, and in the Dinaric Alps in Montenegro and Bosnia-Herzegovina.
In Bulgaria it is found above about 1100m to about 2200m (Kolev) (montane and sub-alpine zones) very locally in the Rila Mountains, but also on Vitosha Mountain, just south of Sofia, and in the Osogovska Planina on Bulgaria’s western border with Macedonia.
Among other differences it has deeper orange uppersides than its common congener the Clouded Yellow (Colias crocea), nevertheless females can sometimes be hard to distinguish. It flies in June and July in areas where its bushy hostplant, Chamaecytisus absinthioides is abundant.
Although it is classed as of "Least Concern" on the European Red List of Butterflies (van Swaay et al. 2010), Kolev considers it to be "Vulnerable" (Butterflies of Bulgaria website) because of its very limited and localised global distribution.
This is one of four species protected by law in Bulgaria.
This species occurs in the montane and subalpine zones on open mountain slopes and gullies where its hostplant is abundant.
Recorded in 2 (0.1%) of the 1900 10km squares of Bulgaria.
Last recorded in July 2014
Recorded date range (Adult): 08 July to 19 July