Q: Roridula species

• R. gorgonias
• R. gorgonias
• R. dentata

A: There are only two species, and they are not known to hybridize. Both plants are woody shrublets that produce long, narrow leaves covered with resinous droplets. The plants are green to yellow-red in color. Differences between the two plants are given below.

Roridula dentata L.
The larger of the two species. It grows to be up to 2 meters tall, and its leaves are up to 5 cm long and about 3 mm wide. The leaves have lateral teeth. The flowers are on long pedicels, with petals about 12 mm long. Plants range from the mountains in the Cape Fold mountains of the Tulbagh, Ceres, and Clanwilliam districts, in altitudes of 900-1200 meters. It reportedly occurs at fynbos sites that are more arid than those that support Roridula gorgonias.

Roridula gorgonias Planch.
A shrublet that grows up to about 40 cm tall, with nondentate leaves that are up to 12 cm long. The flowers have petals about 15 mm long, and are on short pedicels. Plants live in marshes, seeps, or sphagnous wetlands. These habitats are more wet, and are more coastally distributed, than Roridula dentata sites. Specifically, they are found in the Somerset West, Stellenbosch, Caledon, and Swellendam districts at 100-900 m elevation.

Page citations: Carlquist, S. 1976; McPherson, S. 2008; Obermeyer, A.A. 1970.