The taxonomy of problematic Mallomonas species (Synurophyceae). II. Mallomonas costata and M. galeiformis

Whole cells of Mallomonas costata and Mallomonas galeiformis with complete scale and bristle complements present few problems for their identification by TEM. Individual scales however, such as those usually encountered in paleolimnology, have often been difficult to identify in isolation. Both species occur in collections from Ontario, Canada, but M. galeiformis is apparently more acidophilic than M. costata . Several differences in structure of scales from both species are described which, if used as criteria for distinguishing between the two species, should facilitate identification of individual scales.