Okáč Proterebia afra (Lepidoptera: Nymphalidae) je druhem asijských stepí s reliktním rozšířením na Balkáně: v chorvatské Dalmácii a řeckém pohoří Askion. Je tam hojný, ale čelí hrozbě zarůstání biotopů. Druh žil od pozdních třetihor v horách severního Íránu a na Zakavkazsku, odkud se rozšířil do zbytku svého areálu. V ruských a kazašských stepích žije již minimálně po několik dob ledových i meziledových.

Citovaná literatura:

BARTOŇOVÁ, Alena, et al. Isolated Asian steppe element in the Balkans: habitats of Proterebia afra (Lepidoptera: Nymphalidae: Satyrinae) and associated butterfly communities. Journal of Insect Conservation, 2017, 21.3: 559-571. BARTOŇOVÁ, Alena, et al. Range dynamics of Palaearctic steppe species under glacial cycles: the phylogeography of Proterebia afra (Lepidoptera: Nymphalidae: Satyrinae). Biological Journal of the Linnean Society, 2018, 125.4: 867-884. KLEČKOVÁ, Irena; KONVIČKA, Martin; KLEČKA, Jan. Thermoregulation and microhabitat use in mountain butterflies of the genus Erebia: importance of fine-scale habitat heterogeneity. Journal of Thermal Biology, 2014, 41: 50-58. PEÑA, Carlos; NYLIN, Sören; WAHLBERG, Niklas. The radiation of Satyrini butterflies (Nymphalidae: Satyrinae): a challenge for phylogenetic methods. Zoological Journal of the Linnean Society, 2011, 161.1: 64-87. THOMAS, J. A., et al. Intraspecific variation in habitat availability among ectothermic animals near their climatic limits and their centres of range. Functional Ecology, 1999, 13: 55-64. ZINENKO, Oleksandr, et al. Mitochondrial phylogeny shows multiple independent ecological transitions and northern dispersion despite of Pleistocene glaciations in meadow and steppe vipers (Vipera ursinii and Vipera renardi). Molecular phylogenetics and evolution, 2015, 84: 85-100. Použitá a doporučená literatura: ÁLVAREZ-LAO, Diego J.; GARCÍA, Nuria. Geographical distribution of Pleistocene cold-adapted large mammal faunas in the Iberian Peninsula. Quaternary International, 2011, 233.2: 159-170. HEWITT, Godfrey M. Post‐glacial re‐colonization of European biota. Biological journal of the Linnean Society, 1999, 68.1‐2: 87-112. KAHLKE, Ralf-Dietrich. The origin of Eurasian mammoth faunas (Mammuthus–Coelodonta faunal complex). Quaternary Science Reviews, 2014, 96: 32-49. KUDRNA, Otakar; PENNERSTORFER, Josef; LUX, Kristian. Distribution atlas of European butterflies and skippers. Schwanfeld: Wissenschaftlicher Verlag PEKS e.K., 2015.
de LATTIN, Gustaf. Grundriss der Zoogeographie. Stuttgart: Gustav Fischer verlag, 1967. PEÑA, Carlos; WAHLBERG, Niklas. Prehistorical climate change increased diversification of a group of butterflies. Biology Letters, 2008, 4.3: 274-278. SCHMITT, Thomas. Molecular biogeography of Europe: Pleistocene cycles and postglacial trends. Frontiers in zoology, 2007, 4.1: 11. WILLIS, Katherine J.; McELWAIN, Jennifer C. The evolution of plants. Oxford University Press, 2002.

Proterebia afra (Lepidoptera: Nymphalidae) occupies the Eurasian Steppe, with a relict distribution in the Balkans: the Croatian Dalma­tia and the Greek Askion mountain range, where it is abundant but might suffer from forest encroachment. Since the late Ter­tiary period, it has been present in Nor­thern Iran and Transcaucasia, from where it expanded. Furthermore, it inhabited the Russian and Kazakh Steppe for at least several glacial and interglacial periods.