Ultrastructure and systematics of two new freshwater red cryptomonads, Storeatula rhinosa, sp nov and Pyrenomonas ovalis, sp nov.

The ultrastructure and systematics of two red colored freshwater cryptomona ds, Storeatula rhinosa, sp. nov. and Pyrenomonas ovalis, sp. nov., are desc ribed for the first time. Storeatula, which had been described from marine waters only, has a single inner periplast sheet and a fibrous surface perip last component. Cells lack a furrow but possess a gullet, a bilobed chlorop last connected by a pyrenoid and a nucleomorph located in an indentation of the pyrenoid. This freshwater Storeatula possesses the same general featur es as the marine species, but it has a contractile vacuole and lacks the lo bed chloroplast of S. major. P. ovalis has the generic characteristics desc ribed for marine species of Rhodomonas. These characteristics include a sho rt furrow, a deep gullet, square inner periplast plates with beveled corner s, a slightly fibrillar surface periplast component, a single chloroplast w ith two lobes connected by a pyrenoidal bridge and a nucleomorph located in an indentation of the pyrenoid.