Aphantopus hyperanthus · tamsusis satyras

EN · ringlet
DE · Schornsteinfeger
LT · tamsusis satyras
LV · parastais samtenis
PL · przestrojnik trawnik

• en.wikipedia.org/wiki/Ringlet
  
• pyrgus.de/Aphantopus_hyperantus_en.html

This butterfly is unmistakable when seen at rest - the rings on the hindwings giving this butterfly its common name.
The caterpillars feed on many grasses.