The survey is a floristic inventory of Coscinodiscophyceae and Fragilariophyceae diatoms from lotic systems of Litorânea watershed, east Paraná, Brazil. Diatoms were collected from periphytic and planktonic microhabitats on December 1998, February and July 2000. Nine rivers were sampled: Iporanga, Nhundiaquara, Nunes, Cachoeira, Salto, Cambará, Onça, Cabaraquara and Engenho. Twenty taxa were identified. Aulacoseira distans (Ehr.) Sim. var. distans was first recorded in the State. Asterionella formosa Hass. var. formosa and Cyclotella stelligera (Cl. & Grun.) V. Heurck var. stelligera occurred only at planktonic samples and Cyclotella pseudostelligera Hust. var. pseudostelligera e Fragilaria capucina var. vaucheriae (Kütz.) Lang.-Bert. were exclusively registered at periphytic ones.
Diatoms; taxonomy; phytoplancton; periphyton; lotic system
