XVI International Botanical Congess

This study is based on Euglena ehrenbergii, E. ehrenbergii var. baculifera, and E. subehrenbergii collected from fresh water bodies in New Jersey. Current classifications of these species, based on light microscopy, conflict. Some of the features used in these classifications, such as presence and shape of paramylon, degree of metaboly, and shape of the posterior end, are transient in nature and make species distinctions unclear. Electron microscopy may reveal additional stable morphological characters that will aid in classification of the species into one or more taxa. Our preliminary ultrastructural investigations have revealed pyrenoids in chloroplasts and a unique pellicle structure. These features are not described in the original species diagnoses, but may be morphologically informative and useful for clarifying the position of these species.