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New Oxalis species named after SU botanist
Author: Wiida Fourie-Basson
Published: 08/11/2016

A botanist from Stellenbosch University, Prof. Léanne Dreyer, has been honoured for her significant contributions to the study of the genus Oxalis by having a newly described species named after her.

Oxalis dreyerae is one of ten new Oxalis species recently discovered in the arid Richtersveld – an area that was previously assumed to be relatively poor in diversity.

B_Leanne Dreyer_Oxalis 003 (2).jpg

Better known as sorrel or 'surinkies' in Afrikaans, these plants are native to South America and South Africa, with about 500 different species in the genus. The genus was first described by Swedish botanist Carl Linnaeus in 1753, but the last major work on the genus in South Africa was done 70 years ago, in 1944.

Prof. Dreyer was part of the field trip to the Richtersveld in 2011 and again 2012 to look for new Oxalis species: "We got wind that the area received good winter rains. So we packed up and for two weeks surveyed the area as far and wide as possible."

It was during the second trip that Prof. Dreyer had to return home after a break-in at her home in Stellenbosch. Her colleagues, Dr Francois Roets and Dr Kenneth Oberlander, then made use of the opportunity to name a new species after her after they collected it in her absence.

O. dreyerae is described as a striking species with large funnel-shaped white flowers. It typically grows in rock crevices between granite boulders on the south-facing slopes of the Richtersveld Conservancy.

Prof. Dreyer says the Richtersveld probably harbours many more secrets and surprises in terms of its flora: "Oxalis plants are difficult to find. The bulbs are underneath the ground and the plant only flowers after sufficient rain. The Richtersveld is also not the easiest of terrains to explore. This has led to the assumption that the region does not harbour many Oxalis species."

During the two field trips they literally went off the beaten track to look for these small plants: "Our trips have revealed a wealth of Oxalis species, including at least ten undescribed species. Nine of the ten new species are endemic to the Richtersveld, and seven of them are extremely scarce".

"This means the levels of endemism for Oxalis in the Richtersveld are higher than the relatively well-explored Namaqualand," she adds.

On the photo above, Prof. Léanne Dreyer with a plate of the newly-found Oxalis species named after her, O. dreyerae. The plate was presented to her as a surprise by fellow researchers Dr Kenneth Oberlander and Dr Francois Roets in honour of her significant contributions to the study of the genus Oxalis

Contact details:

Prof. Léanne Dreyer

Department of Botany and Zoology, Stellenbosch University

Tel: 021 808 3070