Original paper

Two new planktic species of Eunotia (Bacillariophyceae) from freshwater waterbodies in North Carolina, U.S.A.

Siver, Peter A.; Hamilton, Paul B.; Morales, Eduardo A.

Abstract

Two new species of Eunotia, E. croatana sp. nov. and E. pseudofragilaria sp. nov., are described from freshwater lakes situated along the Atlantic Coastal Plain of North Carolina, U.S.A. Both taxa were found dominant in the plankton community and appear to be morphologically well adapted for an open water existence. The species are similar in being long and slender in form, only slightly asymmetrical about the apical axis, with significantly reduced raphe slits and a series of siliceous ridges along the valve margin. The taxa differ in valve morphology and overall dimensions. Eunotia croatana possesses a unique symmetry where in valve view one apex is bent upwards and the other downwards, resulting in a sigmoid shape in girdle view. Eunotia pseudofragilaria has narrow, lanceolate valves that are not sigmoid in girdle view. Eunotia croatana and E. pseudofragilaria are described from very acidic, poorly buffered, dilute lakes high in dissolved organic material.

Keywords

carolina bayscroatan national foresteunotianew speciesnorth carolinaplanktonpocosin national wildlife refuge