Butterflies (Lepidoptera: Rhopalocera) of the Croatian islands: an update on published records and new surveys of Pasman and Ugljan

摘要

Since the publication of the first overview of the butterfly fauna of the Croatian islands in this journal in 2008, additional historical records and recent articles on the butterfly fauna of Hvar, Mljet, Lastqvo and Krk have added further information. The 20-year survey of Krk by Habeler has increased the species recorded to 104, which makes it the most butterfly-rich island in the Mediterranean. A summary of these new records is given.Fieldwork was carried out from 2008 to 2010 on islands not previously surveyed, particularly Pasman and Ugljan, where six visits at different times of the flight season yielded 50 species for the former and 43 for the latter. The butterfly fauna of thesetwo islands is surprisingly diverse, including some rare habitat-specialists like Gegenes pumilio, Iolana iolas, Pseudophilotes vicrama and Pieris ergane. When compared to that of the previously surveyed island of Dugi otok, which lies further offshore,surprisingly, some butterflies that occur commonly on the mainland are present on Dugi otok (e.g. Hipparchia fagi, Gonepteryx rhamni) but absent from Pasman and Ugljan. The scarcity of Hipparchia semele is attributed to abandonment of grazing. The survey work showed that butterfly distribution was concentrated at just a few localities on each island, underlining the importance of identifying and conserving such localities on all the Croatian islands. Records are also included from the two smaller islands Vir and Silba.The information gathered shows that the islands host an important part of Croatia's butterfly diversity (60% of the species) and merit focused nature conservation efforts and better understanding of butterfly distributions through further surveys, especially of some large islands such as Cres/Losinj in the north, and Hvar and Korcula further south.