A very local and rare species in Bulgaria and indeed in Europe. Recent Bulgarian records are from the karst area south of the Western Stara Planina. Records are from quite a wide area and it also occurs over the border into Serbia (where most of these photos were taken). It was formerly recorded from the Bourgas area near the Black Sea coast (for more details see e.g. Zdravko Kolev's website at: http://www.butterfliesofbulgaria.com/muscri.html).
This species is very similar in appearance to its co-gener the Tessellated Skipper (Muschampia tessellum) (which occurs very locally in the Eastern Stara Planina), with which it could easily be confused. The Spinose Skipper is similar in size to a larger than average Pyrgus species., but theTessellated Skipper is usually appreciably larger, which is a helpful distinguishing feature once one is familiar with the two species. Another distinguising feature is illustrated in the comparison picture shown above.
It is thought that the larvae feed on cinquefoils, but this appears to be unconfirmed.
Sparsely vegetated rocky karst limestone hills.
Recorded in 6 (0.3%) of the 1900 10km squares of Bulgaria.
Last recorded in June 2019
Recorded date range (Adult): 08 June to 13 June