Apatura metis (Freyer, 1829) – Freyer’s purple emperor
The Freyer’s purple emperor is strictly protected in Serbia and marked as vulnerable (VU) in preliminary national Red List of Butterflies. It is also listed in European Habitats directive (in Annexes II and IV) and in Bern convention, which puts higher conservation priority for this species in Europe and the neighbouring region.
One part of the field studis during the Rufford project „Endangered Serbian Butterflies – working together“ is planned for the target species, among which is this purple emperor. The data that we have for the distribution of this butterfly are very scarce, and one of our aims was to fill this data gap and get more realistic distribution of the Freyer’s purple emperor in Serbia.
Freyer’s purple emperor is lowland species and all the records from Serbia are below 100 m of altitude. There are two generations, the first in June and the second starting from July untill the end of August. Individuals of the second generation are notably smaller. The first habitat description and the apearence of the larval stages (of European populations) for this purple emperor is given by Lorković and Silađen in 1982. The authors noted very high similarity of this taxa with relative species of Apatura ilia, especially with form A. i. clytie.
During the reasearch in 2018 we visited Danube, Sava and Tisa rivers. Known habitats of the Freyer’s purple emperor are located in specian nature reserve “Gornje Podunavlje” (Apatin-Sonta), reserve „Karađorđevo“ and on the banks of Danube river near Bačka Palanka, Plavna and Bačko Novo Selo (take a look on the map on Biologer). Despide detailed search during this ans several previous years, no butterflies were recorded near Sava river and in special nature reserve „Zasavica“, although there are literature data about this species presence. The findings close to Tisa river are “doubthful”, but some preserved specimens exist in the insect collections of our associates. We plan to check this records soon in order to check the validity of the records. Currently there are no recently confirmed records on the Freyer’s purple emperor in Serbia out of the province of Vojvodina, although looking at the Bulgarian populations of this species one can conclude that species can also be expected in the eastern parts of the country.
In the Danube region Apatura metis could be found in thin flooded stripes reachin the river bent. The first generation is mostly recorded closer to the bent, since the water level is high in this period and the river shore in not easily approachable. The butterflies of the second generation are usually found basking at the very shore of the Danube, on the sandy soil, rocks or in the vicinity of the host plant – white willow (Salix alba). The butterflies could also be observed on the wet roads leading through the floodplains of the Danubian forests. Freyer’s purple emperor is usually spending most of the time high in the tree branches and this is a reason why females are not so easy to observe. Collecting data about this species is also hard due to high water level of our largest rivers, torning our fiest studies into some sort of a chalange.
One is certain. We still don’t know the biology and ecology of this species and further research will help to get clear picture on the Freyer’s purple emperor distribution in Serbia and on the Balkan.
You can see some more details about this interesting species in Biologer database: https://biologer.org/en/groups/9/species/348
Text: Ivan Tot