B. Papp szerk.: Studia Botanica Hungarica 38. 2007 (Budapest, 2007)

Bercu, Rodica: On the anatomy of the endangered plant species Asplenium lepidum (Aspleniaceae)

Studia bot. bung. 38, pp. 125-131, 2007 ON THE ANATOMY OF THE ENDANGERED PLANT SPECIES ASPLENIUMLEPIDUM (ASPLENIACEAE) R. BERCU Department of Botany, Faculty of Natural and Agriculture Sciences "Ovidius" University, Mamaia Str. 124, RO-900590, Constanza, Romania; rodicabercu@yahoo.com Studies of the endangered fern species Asplenium lepidum revealed new data and features on the anatomical structure of the adventitious root, the rhizome and the leaf (petiole, rachis and pinnulae). The structures of the petiole and rachis were analysed on serial cross sections, beginning from the base up to the rachis tip, with special attention to the changes and organisation in the vascular system. With six figures. Key words: adventitious root, anatomy, Asplenium lepidum, petiole, rachis INTRODUCTION Asplenium lepidum C. Presl, known as spleenwort, is a small fern with tufted leaves 5 to 10 cm in length. It has a long green petiole, brown at the very base and the blade possesses many glandular hairs, broadest at base. The pinnulae cutting is deep but variable. This little fern, in natural habitats, used to grow on limestone overhangs and cliffs and in the side of the caves, often in dry situations, even below 1,000 m in altitude. The spleenworts develop in spring and fructify in summer, the leaves drying in winter. Asplenium lepidum is a rare and endangered fern species in the native flora of Transylvania (Romania). It occurs in the region of Cris - Cheile Turzii at the broad alcove, and in the Ford Cave - Crisului Ford nature reserve. Previously it was also found at Suncuius (Beius), Banat (Baile Herculane zone) - Columbaci Cave and Gorj region (Polovraci) in the Oltetului Gorges (SAVULESCU 1952). Generally, fern structures, especially those concerning the changes and variation in the vascular system and organisation of the vegetative organs, are little known, especially in the case of Asplenium lepidum C. Presl.