New records of Mallomonas and Synura species (Phylum Ochrophyta) from the Mooi River, South Africa.

• Four Mallomonas and one Synura species were found in the Mooi River, South Africa. • Cell morphology, dimensions and photographs of each species are presented. • The taxonomy, ecology and geographical distribution of each species are discussed. • Two Mallomonas species are reported for the first time in Africa. • Three Mallomonas and one Synura species are reported for the first time in South. • Africa Four species of the genus Mallomonas (M. alpina, M. annulata, M. caudata , and M. cratis), a unicellular silica-scaled chrysophyte, and one species of Synura (S. curtispina), a colonial silica-scaled chrysophyte, were found in the Mooi River, North West Province, South Africa. Entire Mallomonas cells, having intact scales and bristles, were photographed with the scanning electron microscope, enabling accurate species identification. Cells of Synura curtispina, with distinct scales on the surface, was also found. Short descriptions and dimensions of each species are given, and their known geographical distribution and ecological preferences are discussed. Two species (M. annulata and M. cratis) represent first distribution records for Africa, and four species represent first records for South Africa. Only one species (M. alpina) was previously recorded in South Africa. [ABSTRACT FROM AUTHOR]