XVI International Botanical Congess

Relationships among taxa in the genus Euglena have been disputed byphycologists almost since the establishment of the genus by Ehrenberg. The genus originally included photosynthetic and osmotrophic taxa. Subsequently, the genus Astasia and Khawkinea were erected to accommodate the colorless euglena-like taxa. However, differences in the proposed sub-groupings within the genus Euglena still exist depending on the morphological characters emphasized. To assess the congruence of morphological characters with molecular data, we have analyzed the SSU rDNA sequence of several euglenoids. Analyses have shown that A. longa and K. quartana may be more accurately placed within the genus Euglena. The distribution of shared morphological characters (i.e. pellicle type, chloroplast shape, pyrenoid type, paramylon structure) agrees with the major clades found on the SSU rDNA tree.