Abstract
Gyrosigma prolongatum var. closterioi d es is raised to specific status as G. closterioides (Grunow) G. Reid stat. nov. The ultra-structure of G. closterioides, G. fasciola (Ehrenb. ) J. W. Griff. & Henfr., G. prolongatum (WSm. ) J. WGriff. & Henfr. and G. macrum (W. Sm. ) J. W. Griff. & Henfr. is investigated using light and electron microscopy.
