On the presence of Iolana iolas (Ochsenheimer, 1816) in Slovenia
Rudi VEROVNIK1 & Mojmir LASAN2
1 University of Ljubljana, Dept. of Biology, Biotechnical Faculty, Večna pot 111, SI-1000 Ljubljana, Slovenia
2 Glavarjeva ulica 47, SI-1000 Ljubljana, Slovenia
Iolana iolas is one of the largest European lycaenids limited to the southern part of the continent with locally distributed populations extending from south Spain to southern Alps and Balkan Peninsula (Tolman & Lewington 1997). It is a monophagous species, whose distribution is limited by the availability of its larval foodplant Coluthea arborescens L. In the neighbouring regions of Slovenia, this butterfly species is known from NE Italy (Reichel 1992), SW Hungary (Varga Z., pers. com.) and Croatian coastal region south of Rijeka (Jakšić 1988).
For Slovenia, it was mentioned for the first time in the national Red List of Butterflies and Moths (Macrolepidoptera) (Carnelutti 1992), but the author doubted the validity of the information about its presence on Mt. Nanos. The species has been afterwards intensively searched for on the southern slopes of Mt. Nanos in the nineties, but without any success. In the year 2000, a female ex larvae was received by Lasan from Italian collector Bruno Castella, who had collected larvae of Iolana iolas on the slopes of Mt. Nanos in 1990. In 2002, the species was finally confirmed by the authors independently at two separate localities. The currently available information on the distribution of this rare lycaenid in Slovenia is:
-      2.7. 1991 ex larvae – Mt. Nanos, Yugoslavia; Castella B.
-      1.6.2002 – on a road bend NW of Kubed, southern slopes of Mt. Krasca, altitude: 210 m, coordinates: x: 411970, y: 42911; Verovnik, R.
-      13.6.2002 – E of the road to Mt. Nanos, on its southern slopes, altitude: 550 m, coordinates: x: 422927, y: 72443; Lasan M.
An ovippositing female was observed near Kubed on a road verge where few larval foodplants were present. In thirty minutes two males were observed flying restlessly up and
NATURA SLOVENIAE 5(1): 43-44
ZOTKS Gibanje znanost mladini, Ljubljana, 2003
44                                     Rudi VEROVNIK & Mojmir LASAN: On the presence of Iolana iolas .../ SHORT COMMUNICATION
down the nearby bushy slope. On Mt. Nanos only males were found flying near the bushes of Coluthea arborescens. As the foodplant is more widespread in the Primorje region (Jogan & Bačič 2001), we expect to find further localities of Iolana iolas in this part of Slovenia. At most sites only few bushes of the foodplant are avaliable, which is the reason why we consider Iolana iolas a rare and threatened species in Slovenia. As suitable habitats are few and far apart, even limited collecting could cause an extinction of a local population. We thus urge all lepidopterists not to collect adults or larvae and to document the presence of this rare species in Slovenia only by photographing.
Literature
Carnelutti, J. (1992): Rdeči seznam ogroženih metuljev (Macrolepidoptera) v Sloveniji, Varstvo narave, 17: 61-104
Jakšić, P. (1988): Provisional distribution maps of the butterflies of Yugoslavia. Acta entomologica Jugoslavica - editiones separatae I, 214 pp.
Jogan, N., T. Bačič, B. Frajman, I. Leskovar, D. Naglič, A. Podobnik, B. Rozman, S. Strgulc-Krajšek, B. Trčak/N. Jogan (ured.), 2001. Gradivo za atlas flore Slovenije [Materials for the atlas of flora of Slovenia]. Miklavž na Dravskem polju, Center za kartografijo favne in flore, 443 pp.
Reichel, E. R. (1992): Verbreitungsatlas der Tierwelt Österreich. Band 1, Lepidoptera Diurna -Tagfalter, Forschung für Umweltinfromatik, Linz, 106 pp.
Tolman, T. in Lewington, R. (1997): Collins field guide of Butterflies of Britain and Europe, HarperCollins pub., London, 104 pl. 320 pp.