territory of the park. Lakes and streams also diversify the conditions creating wetland habitats for hygrophyte species. Non-vascular plants constitute the least researched part of Pirin's flora. The least studied of them are the algae with 165 species, including two endemics. The largest concentration of algae species is found in Popovo and Kremenski lake groups. The Bryophytes, including mosses, are represented by 329 known species. The number of lichen species is 367, or 52% of Bulgaria's total diversity. Of them 209 species are found in the coniferous forests and 156 — on calcareous terrain. The vascular plants in Pirin National Park include 1315 species of 94 families and 484 genera, or approximately 1/3 of Bulgaria's flora. The flora has largely preserved its indigenous character. The number of vascular plant species is expected to grow in case of future detailed research, especially at lower elevations. The species are divided almost equally to representatives of the sub-Mediterranean and Circumboreal floristic regions. The number of species included in the Red Book of Bulgaria is 114. There are 18 species endemic to the park and another 17 are restricted only to Bulgaria, which makes a total of 35 Bulgarian endemic species. The park is also home to 86 Balkan endemic species. The endemic species restricted to the park are: Pirin poppy (Papaver degenii), Pirin meadow-grass (Poa pirinica), Urumov oksitropis (Oxytropis urumovii), Kozhuharov oksitropis (Oxytropis kozuharovii), Banderishka lady's mantle (Alchemilla bandericensis), Pirin lady's mantle (Alchemilla pirinica), Kelererova asineuma (Asyneuma kellerianum), Pirin sandwort (Arenaria pirinica), Pirin sedge (Carex pirinensis), Pirin fleabane (Erigeron vichrensis), David mullein (Verbascum davidoffii), lesser Pirin fescue (Festuca pirinica), Pirin hogweed (Heracleum angustisectum), Yavorkova rattle (Rhinanthus javorkae), Pirin thyme (Thymus perinicus), Daphne domini, Daphne velenovskyi. Fauna The vertebrate fauna of Pirin National Park consists of 229 species. The number of mammal species is 45. The distribution of the mammalian species by order is as follows: Insectivora – 5, Chiroptera – 16, Lagomorpha – 3, Rodentia – 7, Carnivora – 9 and Artiodactyla – 4. The European snow vole is a relict species. Among the species of highest conservation value are brown bear, gray wolf, wildcat, European pine marten, wild boar, red deer, roe deer and Balkan chamois. The small mammals, especially rodents and bats, are not fully studied in the whole territory of the park. The total number of bird species is 159. Of them 91, or 57%, are passerine. Three species are