Botanic Gardens Trust, Sydney, Australia

What - not another name change?

Kangaroo grass
Themeda triandra Forssk. [Synonym = Themeda australis (R.Br.) Stapf] at NSW Herbarium

Botanists frequently hear the plea of the horticulturist. Please can you stop changing the names!

One recent change here at the herbarium was for kangaroo grass, a species distributed Australia-wide. Themeda is its genus name and the species which was known as Themeda australis is now to be called Themeda triandra. The two names have been synonymous for a number of years with NSW trailing the name change. The change has been taken up by all other major Australian Herbaria. On staff we have Dr Richard Jobson who is the botanist curating and studying the grasses.

So why have we changed the name?

The reason for this name change is that despite high levels of morphological variability within South African and Australian populations, there is an absence of any strong characters differentiating taxa between these trans-continental populations. In addition, the decision is also based on the results of a recent unpublished study that found little genetic variation between Australian and South African populations (Taylor CL & Barker NP (unpublished) Genetic diversity of Themeda triandra Forssk populations in South Africa with comparisons to Australian populations). One aspect of past studies was looking at chromosome morphology. However any differences observed with these cytological studies are no longer supported with the recent genetic work.

Dr Richard Jobson has just received a grant through ABRS - Australian Biological Research Study to study the genus Themeda, as below:

Phylogeny, Phylogeography, and species limits within the genus Themeda Forssk. (Poaceae).

Themeda is a genus of 18 species with five present in Australia. Two of these are introduced, and three are native and distributed across all Australian states, PNG, Malesia and New Zealand. This project aims to examine relationships among the Australasian species incorporating this data with the 15 other species distributed in the Old World Tropics. The project will also address taxonomic issues at the infraspecifc level, examining potential hybridisation zones between cytological forms, and morphological and phylogeographic patterns within complexes of native species. The study will produce an account for inclusion in the Flora of Australia.

Themeda triandra has a particularly wide distribution in the world and in Australia, it is found in all states and territories, and overseas it is found in Africa, Asia and the Pacific. It commonly grows in grassland and open woodland communities.

Themeda triandra was first described and named in 1775 by Pehr Forsskål, a Finnish botanist and pupil of Linnaeus. It was published 5 years after Banks and Solander had collected kangaroo grass from the east coast of Australia.

The PlantNET website is now up-to-date with this name change and can be viewed here.


 

Themeda triandra

Themeda triandra at PlantBank