Taxonomic position of Pinus ceciliae (Pinaceae) endemic for Balearic Islands as revealed on needle characteristics

Abstract

The Cecilian pine (Pinus ceciliae) is endemic to Balearic islands (Spain). It is a small taxon, sometimes treated as synonym of Aleppo pine (P. halepensis), to which is closely related, differing mainly with dense crown shape and upright branches. The other characteristics, which differ between P. ceciliae and P. halepensis concern the cone scale and needle length only. We examined biometrically needles of Cecilian pine from Mallorca (5 tress) and Menorca (9 trees) islands, and compared them to Aleppo pine populations represented by 30 trees from each island. Each tree was represented by 5 needles, and they were studied with respect to 17 morphological and anatomical characteristics. We detected that needles of the Cecilian pine were smaller, but only when compared to the Aleppo pine from the same island. In general, this difference was also observed in the number of resin canals, number of stomata and stomatal rows. Interestingly, the proportions of the needle dimensions pattern were similar in both taxa. In conclusion we stated the results support the taxonomic rank of Cecilian pine as a variety, Pinus halepensis var. ceciliae (Llorens & L.Llorens) L.Llorens, Fl. Països Catalans, 1: 197 (1984).