摘要: Mt Kozjak is an elongated mountain ridge situated in central Dalmatia, just above the Riviera of Kaštela near Split. It was well surveyed a century ago by Hermann Stauder who recorded 38 butterfly species. Among these, Papilio alexanor was the most prominent discovery. During our surveys from 2007 to 2018, we recorded 82 butterfly species at 19 localities bringing the total of observed species to 87. We managed to confirm the presence of Papilio alexanor more than hundred years after the first observation in the area. The occurrence of some additional rare and interesting species like Carcharodus orientalis, Pyrgus sidae, Pyrgus serratulae, Parnassius mnemosyne, Euchloe ausonia, Cupido osiris, Polyommatus admetus and Hyponephele lycaon is discussed in more detail. The butterfly fauna of Mt Kozjak is very diverse given its geographic position, low habitat diversity and size. Abandonment of pasturing and subsequent overgrowing of calcareous grasslands is the most important factor causing long term butterfly decline on Mt Kozjak.