Notes on the taxonomy and nomenclature of the algal classes Eustigmatophyceae and Tribophyceae (synonym Xanthophyceae)

The systematics of the Eustigmatophyceae are revised at the level of species, genus, family and order. All known species are included in the Eustigmatales, which is divided into four families: the Eustigmataceae Hibberd includes Eustigmatps Hibberd and Vischeria Pascher, each with three species; the Pseudocharaciopsidaceae includes only Pseudocharaciopsis Lee & Bold with two species; the Chlorobotryaceae includes only Chlorobotrys Bohlin with one species and the Monodopsidaceae includes Monodopsis Hibberd with one species and Nannochloropsis Hibberd with two species. Eustigmatophyta and Eustigmatophyceae are published as typified names for the division and the class, respectively, both based on Eustigmatos. Tribophyceae, based on Tribonema , is published as the typified name for the class previously called Xanthophyceae. Nannochloris coccoides Naumann is chosen as lectotype of the chlorophycean genus Nannochloris Naumann.