A mass development of benthic Sarcinochrysidales (Chrysophyceae s.l.), especially of Chrysoreinhardia giraudii comb. nov. (basionym: Tetraspora giraudii) and Nematochrysopsis marina comb. nov. (basionym: Tribonema marinum), is reported from the Corsican coast. Morphology, habitat and seasonal development of these taxa as well as of the less regularly observed Chrysonephos lewisii and of some Chrysophyceae s.l. associated with Chrysoreinhardia giraudii sheaths are presented.