Characteristics of heteroblasty in Hladnikia pastinacifolia (Apiaceae), a rare endemic from Slovenia

Hladnikia pastinacifolia, the most prominent endemic plant species in Slovenia, is rare and protected because it a stenoendemic paleoendemic restricted to area of Trnovski gozd (W Slovenia). However, this can be found various habitats. The disparity between non-specific habitat preference its rarity has not been sufficiently explained. Here we focus on functional morphological features that are indicative for ecology species: anatomical characteristics leaves. pastinacifolia exhibits heterophylly during ontogeny (heteroblasty). We aimed describe compare three H. leaf morphotypes among them relation Therefore, compared thickness lamina, spongy palisade parenchyma, upper lower epidermis number stomata epidermis. These measurements were further used calculate ratio index density stomata. determined heteroblasty belongs Apium-type. Results showed five-pinnate leaves distinct type, being thickest, with highest numbers abaxially. When habitats, from scree thickest according all tissue layers studied. indices calculated less useful distinction types