Using SEM, TEM and light microscopy, extant material of the genus Stellarima Hasle & Sims collected along the coast of Chile from 36-degrees42'S to 41-degrees49'S was studied. The only species found was S. stellaris (Roper) Hasle & Sims; this taxon had been previously described for chilean waters as Coscinodiscus stellaris Roper. A diagnosis of the species and comments about variability and constancy of morphological characters are given.