XVI International Botanical Congess

Historically, the chrysophytes started as a loose cluster of mainly flagellate species, the first ones described more than 200 years ago, but it was not until 1914 that Pascher accommodated the golden-brown flagellates together with their presumed nonmotile and colorless relatives in the new algal class Chrysophyceae. The class grew and changed during the next decades, leading to the monumental classification system of Bourrelly (1957/1968/1981), followed by Starmach (1985), that represented the culmination of the great era of light microscopy. Even as these works were being published, an enormous revolution was occurring and being continued until now as new data were provided by electron microscopy, pigment analysis and molecular gene sequence comparisons, showing that the Chrysophyceae sensu lato is an unnatural assemblage, containing a wide range of mutually unrelated taxa.