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

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

Remarkable are the loosely arranged mesophyllous cells, the epidermis interrupted by the presence of stomata, and the endodermis cells with parenchymatous sheath value (Fig. 5A, B). The pinnulae appear, in cross section, to consist a single layer of regularly arranged epidermal glandular cells, covered by a thin cuticle (Fig. 6). The continuity of the lower epidermis smaller cells is broken by the presence of stomata. The mesophyll is undifferentiated into palisade and spongy tissue. Noticed by early authors for Aspleniaceae species (POIRAULT 1893, OGURA 1938), the mesophyll consists of a number of branched and lobed cells, arranged into a number of rows, forming a system of intercellular spaces. The poorly developed vascular system of the midrib is represented by a hadrocentric vascular bundle. The vascular bundle is surrounded by a bundle sheath (Fig. 6). Fig. 5. Cross section of the subtcrminal rachis (6.5 cm from the petiole base). A: portion with spongy tissue (200); B: the vascular bundle (x290). (Ep = epidermis, IS = intercellular space, Ms = mesophyll, Ph = phloem, S = stoma, ST = spongy tissue, VB = vascular bundle, X = xylem (orig.)). VB S Fig. 6. Cross section of pinnulae (x200). (GC = glandular cells, IS = intercellular space, LE = lower epidermis, Ms = mesophyll, S = stoma, VB = vascular bundle (orig.)).