The genus Callitriche in northeastern Italy:: First systematic contribution

The aim of this paper is a better understanding of the distribution and taxonomy of the species of the genus Callitriche L. in northeastern Italy. In our country, only a few studies dealing with this topic have been carried out. The taxa have been collected in the neighborhood of Padua and Treviso (Veneto Region) and studied from karyological, micromorphological (LM and SEM), macromorphological, and statistical points of view. The specimens are situated in the Herbarium of Padua University (PAD). Knowledge about the distribution area of C obtusangula has been widened; the presence in Italy of C. platycarpa has been confirmed and a hybrid collected. On the basis of karyological and morphological data and their statistical analysis, the hybrid could be a cross between C. obtusangula and C. stagnalis.