- Knowltonia capensis
- Knowltonia capensis (L.) Huth
- Knowltonia moorei
- Knowltonia moorei (Espinosa) Christenh. & Byng
- Knowltonia sp.
- Knowltonia transivaalensis
- Knowltonia transivaalensis Szyszyl.
- Knowltonia transvaalensis
- Knowltonia transvaalensis Szyszyl.
- Knowltonia transvaalensis Szyszyl. var. transvaalensis
- Knowltonia vesicatoria
- Knowltonia vesicatoria (L.f.) Sims subsp. grossa H.Rasm.
- Knowltonia vesicatoria (L.f.) Sims subsp. vesicatoria