Southern swallowtail
Southern swallowtail(Papilio alexanor, [1800]) is one of the most charismatic diurnal butterflies in Croatia. It is one of seven easily recognizable and large diurnal butterflies of the swallowtail family (Papilionidae) in Croatia, characterized by an imago wingspan of 55 to 70 mm and females that are usually larger than males. The imago is easily recognized as it takes the form of two almost vertical lines in the central section of the front part of the wing. The actual geographical distribution of the species in Croatia was unknown and unexplored for decades, and, until recent systematic multi-year research, it was considered extremely rare and known only from a few historical localities in Istria, Krk and Dalmatia. The southern swallowtail is rarely seen due to its remote and inaccessible habitats on steep rocky limestone slopes and south-facing cliffs. Today, it is known that the species is widespread in several localities in Dalmatia, south of Split, where its imago can be seen flying along the rocks and next to the woolly thistle (Cirsium eriophorum) and the bird vetch (Vicia cracca). Due to the highly fragmented Euro-Central Asian distribution area, caterpillar host plants differ in certain areas of Europe. This is probably due to the ecological needs of the caterpillar host plants, some of which are pioneer species that select eroded and poor soils. Research has shown that the swallowtail populations have a preference for one type of umbellifers, and, due to different flowering times, they can use up to three types. In Italy and France, the species' caterpillar feeds on the seeds and flowers of Ptychotis saxifraga, Hercules' all-heal (Opopanax chironium), Seseli montanum and honewort (Trinia glauca), in Greece it feeds on Hercules' all-heal (Opopanax chironium), species of the Pimpinella genus and species of the Ferulago genus, whereas in Croatia it only eats Hercules' all-heal (Opopanax chironium). The caterpillar is similar to the caterpillar of the southern swallowtail with a chartreuse ground color and transverse black and red stripes on its back. The southern swallowtail hibernates in the pupal stage. It creates one generation per year, and its imago appears between the beginning of April and the end of July. The southern swallowtail is endangered due to a lack of favorable O. chironium habitats in which it grows in abundance, as they are under great pressure of urbanization and serious fragmentation. The main threat to its survival is the destruction of favorable habitats along the edges of roads and slopes, potential illegal collecting, and the constant reduction of populations due to the local disappearance/extinction of the species in historically known locations. The species is protected by the Nature Protection Act in the category of strictly protected native wild taxa, so collecting adult speciemen of the species, as well as specimen in the caterpillar stage, is illegal. The species can be found in Appendix IV of the Directive on the conservation of natural habitats and of wild fauna and flora (Council Directive 92/43/EEC) and Appendix II of the Berne Convention, and it is considered extremely sensitive to climate change as a species of extremely high risk of categorization in the Climate Risk Atlas of European Butterflies.
Marsh fritillary Euphydryas aurinia
Marsh fritillary (Euphydryas aurinia) is one of the most recognizable species from the brush-footed butterflies family (Nymphalidae). It was named after the type of habitat in which it most often resides, namely wet meadows. Two ecological types of this species are known in Croatia - populations inhabiting the wet grasslands of the continental region and populations inhabiting the dry grasslands of the Alpine and Mediterranean regions of Croatia. In the continental region, its populations are usually isolated with fragmented suitable habitats. The destruction of such smaller wetlands and changes in the water regime represent the most pronounced threat to the continental region, which can lead to the local extinction of the species. In the Alpine and Mediterranean regions, the species' populations are more numerous and present on larger pastures and grasslands, where succession caused by the reduction of extensive grazing poses the main threat. Recent research has confirmed the presence of the species in almost all historically known areas and numerous new localities in all regions of Croatia, with numerous populations throughout the Dalmatian hinterland. The marsh fritillary lives in wet limestone open meadows with feeding plants from the genera of pincushions (Scabiosa), widow flowers (Knautia), knapweeds (Centaurea), honeysuckles (Lonicera), Plantago,Teucrium, as well as devil's-bit (Succisa pratensis). Host plants of its caterpillar include the great yellow gentian (Gentiana lutea), the common honeysuckle (Lonicera periclymenum), the dwarf pincushion flower (Scabiosa columbaria) etc. Females choose larger, more prominent host plants or smaller areas with lower vegetation where host plants grow in great abundance. Females lay up to 350 round yellow eggs in piles on the underside of leaves, and, at the end of July, caterpillars emerge from them. The species' caterpillars have a dark to black ground color and prominent bristles on the body. At the beginning of their development, the caterpillars do not feed individually, but rather colonially and in small silk webs. Starting from September, the marsh fritillary hibernates colonially in the fourth life stage of the caterpillar in winter hibernation webs, its silky shelter. At the end of March of the following year, after hibernation, caterpillars in their fourth life stage stop the "collective" feeding, and so in their fifth and sixth stages they feed individually. From the end of April to the beginning of May, the species lives in the pupal stage, and, in the first or second week of May, depending on the weather conditions, an adult butterfly in its reproductive development phase emerges from it. Marsh fritillaries create one generation per year, and their imago flies from April to July. In Croatia, the marsh fritillary can most often be seen in May and June. The species is threatened by the loss of habitats due to succession, meadow desiccation due to changes in the water regime, or intensification of agricultural production. Parasitoids of the Hymenoptera order also greatly affect the decrease in the number of the fritillary's population. Marsh fritillaries are protected by the Nature Protection Act in the category of strictly protected native wild taxa. The species can be found in Appendix II and IV of the Directive on the conservation of natural habitats and of wild fauna and flora (Council Directive 92/43/EEC), and its preservation is among the preservation goals of 26 areas within the Ecological Network of the Republic of Croatia.
Poplar admiral Limenitis populi
Poplar admiral Limenitis populi (Linnaeus, 1758) is a diurnal butterfly from the Nymphalidae family, characterized by wings of unforgettable beauty and amazing habitats. The species lives in light coniferous and mixed forests, where caterpillar host plants of Populus tremula and Populus nigra grow. Poplar admiral can be found in very limited habitats in Croatia, mainly in forest areas within the continental (Hrvatsko zagorje, Podravina and Slavonia) and mountain regions (Žumberak - Samobor Hills, Gorski kotar and a few areas in Lika, surrounding Lička Plješivica and Velebit). With an imago size of 70 to 80 mm, the poplar admiral is one of Croatia's largest diurnal butterflies. It is easily recognizable due to the dark brown color on the upper side of its wings, smaller white areas on its front wings, and specific white, reddish-brown and grayish-blue patterns on the underside of the wings. Female poplar admirals lay their round green eggs on the upper side of sunlit poplar leaves. Their caterpillars feed on leaves and build a hibernaculum. For the formation of the hibernaculum, they always use new leaves, not the leaves on which they had previously fed. Poplar admirals hibernate in the second caterpillar life stage, and in the spring they feed abundantly on leaves before they pupate, their pupas hanging from poplar leaves. The species creates one generation per year, with their imago flight taking place from June to August. Adult butterflies fly for a very short time, avoiding larger open areas, and females are attached to the tops of trees, which makes them harder to spot. Male poplar admirals sometimes descend to the ground in the morning, primarily to feed on feces and decaying organic matter. For the purpose of courtship, they look for specific landmarks in the landscape, such as taller trees that stand out in the forest canopy (canopy courtship). One of the main causes of endangerment of this species is the result of changes in forestry, i.e. its natural habitats - aspen forests, which do not belong to the group of "quality" forest stands. In Croatia, the species is listed as almost endangered.
Ph.D. Iva Mihoci, Museam Advisor
Croatia Natural History Museam
Ph.D. Martina Šašić Kljajo, Museum advisor
Croatian Natural History Museum
