The endemics are species, whose geographic distribution is limited to a specific region (geographic area, country, etc.). In a European context, the endemism is a significant feature of the Bulgarian flora, as it ranks fourth on the continent when it comes to percentage of floristic endemics – around 9 – 10% of the seed plants. The floristic endemism of Strandja Mountain is much less expressed compared to the national average. The Bulgarian and Balkan floristic endemics in the Nature Park number 55 species.
Strandja Mountain is home for the following endemics – the Strandja Veronica turrilliana and the Strandja Anthemis jordanovii. The Bulgarian endemics are represented by six species and three subspecies – Pyrus bulgarica, Oenanthe millefolia, Galium bulgaricum, Veronica krumovii and others. The Balkan endemics are 39 species and 5 subspecies.
Taking into account the specifics of the geographical location, the geological past and the climate, with a certain degree of conditionality we can view some of the most emblematic for the mountain floristic elements with euxeinos origin as “South Black Sea” endemics. Examples of such euxeinos endemic species, whose distribution is limited along the south coast of the Black Sea between Strandja, the Pontic Mountains and Caucasus, are the Rhododendron ponticum, the Daphne pontica, the Ilex colchica and others.