Isoetes toximontana (Isoetaceae), a new quillwort with green megaspores from the Northern Cape of South Africa

Isoetes toximontana is only the second quillwort reported from the Northern Cape region in South Africa. It occurs in shallow water on the Gifberg. Megaspores are uniformly tuberculate on the proximal surface; their distal surfaces may have occasional rugi along with bullae. They are olive green when dry. Microspores are brown and aculeate. Preliminary field studies suggest that an unexpected diversity of quillworts is found in this region.