A relatively large and diverse class of algae in the chlorophyll a–c phyletic line (Chromophycota). In protozoological classification, these organisms constitute an order, Chrysomonadida, of the class Phytomastigophora. Some workers align Chrysophyceae (golden or golden-brown algae) with Bacillariophyceae (diatoms) and Xanthophyceae (yellow-green algae) in the division Chrysophyta.