Corollospora fuscais a marine ascomycete that based on light microscopy and scanning electron microscopy was previously described as possessing appendaged ascospores with fine longitudinal melanized striations and a ridged surface. Transmission and low voltage scanning electron microscope studies presented here do not support the existence of a ridged surface on the ascospore. Histochemical tests based on the reduction of silver nitrate were used at the electron microscope level to locate melanin in the longitudinal electron-dense deposits in the spore wall.Keywords: ascospores,Corollosporaspp., marine fungi, melanin, ultrastructure, wall structure.