[1] The key diagnostic character of S. prophyllus is its well-developed, firm, shiny spikelet prophylls with relatively long mucros compared to other species in the Schoenus cuspidatus group.

[1] Furthermore, the spikelets of S. prophyllus do not have the conspicuous reddish-purple streaking patterns adjacent to the glume margins that are found in S. bolusii and S.

It appears that part of this problem is caused by the tendency of the southern African Schoenus to form hybrids with each other.

[1] Other genera in tribe Schoeneae include Lepidosperma, Oreobolus, Costularia, Tetraria and Gahnia.

[1] Southern African Schoenus were once classified as Tetraria; however, based on molecular and morphological differences, the two groups are evolutionary distinct.