Morpho-anatomical observations on three Limonium species endemie to the Pelagic Islands.


The study of the morphological adaptations of plants to their environments confirms that anatomical structures evolve (Everi 1962; Fahn 1964, 1978) and change in plants that live in particular environmental conditions, such as an arid-windy climate (Stocker 1960). During our research on endemie plants in Sicily and the surrounding islands, we have performed anatomical studies on the endemic species of the genus Limonium (Colombo & Trapani 1991). This paper describes our observations on Limonium albidum (Guss.) Pignatti, Limonium intermedium (Guss.) Brullo and Limonium lopadusanum Brullo, which are restricted to the Pelagic Islands. Limonium albidum, endemic to Lampione, grows on rocks and cliffs; it is a chamaephyte 20-35 cm high, with non-pulvinate stems, and rugose-tuberculate scapes twinned, rarely only one. In each rosette oblanceolate-spatulate leaves, 28-50 x 5-12 mm, three-veined with a retuse apex and entire margin.; panicle branched in the upper part with straight, crowded fasciculate branches (2-6 per node). Spikes dense, 2-7 cm long with spikelets 6 to 8 flowered; inner bract 5 mm long; calyx 5.5 mm long. Limonium intermedium, endemic to Lampedusa in brackish areas near the port, is a pulvinate chamaephyte, 20-30 cm high, with sturdy, single scapes. Leaves oblanceolate, 20-40 x 4-9 mm, three-veined, progressively narrowed at the petiole, more or less revolute at the edge with a mucronate apex and undulate margino Panide ramose with fasciculate branches. Spikes, 3-10 cm, with spikelets 3-to-4 flowered . Inner bract 4.5-5 mm long; calyx 5-5.5 mm long. Limonium lopadusanum is found along the rocky coasts of Lampedusa and Linosa, in the areas nearest the sea. It is a pulvinate chamaephyte, 7-25 cm high, with single smooth or slightly rugose scapes. Leaves glaucous, obovate-spatulate, 5-20 x 4-10 mm, three-veined, with obtuse apex and entire margino.