Euastrum didelta Ralfs

Euastrum cf. didelta Ralfs complex Scott & Prescott 1961, p. 1, pl., figs 5 –7. Fig. 6d Comments: We encountered a bewildering array of forms that correspond to many already-proposed varities and formae of this supposed taxon. Since we were unable to clearly discern the cellular ornamentation and that these forms may be confused with similar species like Euastrum ansatum Ehrenberg ex Ralfs, we could not confidently identify our material to the species level. However, the other varities of E. didelta that were successfully discerned are indicated below.