@article{Kocic_Horvatic_Jelaska_2014, title={Distribution and morphological variations of invasive macrophytes Elodea nuttallii (Planch.) H. St. John and Elodea canadensis Michx in Croatia}, volume={73}, url={https://www.abc.botanic.hr/index.php/abc/article/view/1008}, abstractNote={<p><span>The invasive species <em>Elodea nuttallii</em> was recorded for the first time in the Croatian flora in 2006, in the drainage channels of Kopacki rit (Baranja). After its establishment, <em>E. nuttallii</em> begins to spread to the eastern and northern part of the drainage channel network from 2006–2009. High water levels are responsible for the linear spreading direction of <em>E. nuttallii</em>, <em>E. nuttallii</em> and <em>E. canadensis</em> show a wide range of morphological variation, which is characteristic of successful invaders. To show morphological variations of two <em>Elodea</em> species, the most important characters indicated in the literature were measured on 24 fresh collected samples from the seven sites in Croatia. In spite of some overlap in leaf length and width between the two <em>Elodea</em> species, the differences of all morphological traits except internode length are statistically significant. In <em>E. nuttallii</em> leaf width, length and internode length show a higher morphological variability as a result of the higher adaptive strategy to environmental parameters. The most reliable morphological characters distinguishing <em>E. nuttallii</em> and <em>E. canadensis</em> are leaf width 0.5 mm below the tip and the angle at the apex. <em>E. nuttallii</em> can be expected to spread to other areas of Croatia.</span></p>}, number={2}, journal={Acta Botanica Croatica}, author={Kocic, Aleksandra and Horvatic, Janja and Jelaska, Sven D}, year={2014}, month={Oct.} }