Author Archives: Michelle

Plant of the Month: Feb 2017

Native Pig-Face, Carpobrotus rossii

Park of the Month in Feb. 2017 was Hallett Cove Conservation Park

Carpobrotus rossii

Herbarium sheet – before the plant is dried, of Carpobrotus rossii. Photo: State Herbarium.

Among the amazing geological features of an ancient landscape a plant which might go unnoticed except when flowering is the native coastal species of Pig-Face, Carpobrotus rossii. In fact, Carpobrotus (Pig-Face) is a world-wide genus of succulent plants, with species native to South Africa, Australia, South America and California.

In South Australia there are four species of Carpobrotus and two species in a closely related genus Sarcozona. Carpobrotus modestus and C. rossii are native to South Australia as are the two Sarcozona, S. bicarinata and S. praecox.

In the coastal areas of Hallett Cove the native species, Carpobrotus rossii is an important member of the ecosystem forming dune protecting ground cover and fruits that animals eat.

Carpobrotus edulis backcross

Carpobrotus edulis flower type, this plant likely to be a hybrid backcross to C. edulis. Photo: C. Brodie.

However, South Australia also has a species of Carpobrotus that is an introduction from South Africa, Carpobrotus edulis, which is listed in the Global Invasive Species Database for 24 countries.

Honorary Research Associate Dr Hellmut Toelken from the State Herbarium of South Australia has been researching the taxonomy of this group and discovered that some pairs of species may form hybrids in South Australian locations. A partnership between the State Herbarium, The University of Adelaide and The Samphire Coast Icon project and Adelaide and Mount Lofty NRM applied molecular techniques to work out what was going on. The DNA analysis that this project conducted revealed that Dr Toelken was correct, and in fact there are many hybrids forming between the local native species and the introduced one. Hybrids are widespread in many areas, in fact where the two species come into close proximity.

A big problem is that while the yellow flowered C. edulis is relatively easy to identify, the hybrids in South Australia appear to be typically pink flowered plants.

Hallett Cove Conservation Park is well known for its geological and archaeological features, and is just outside of Adelaide.

From the parks webpage:

‘In the park ‘glacial pavements’ show evidence of a large glacier that covered the park and surrounding areas 280 million years ago when Australia was part of Gondwana. Over the past 600 million years the Park has undergone a number of changes from being beneath the sea and covered in an ice sheet to being a mountain range. Throughout the Park there is informative signage along the trail that help you understand the story of Hallett Cove Conservation Park.’

F1 C. rossii X C. edulis South Australia. Photo: C. Brodie.

More information is available on the Carpobrotus hybrid project:  Waycott, M. (2016). Hybridisation in native pigface, Carpobrotus rossii. (State Herbarium of South Australia, Adelaide). 8 pp. ISBN 978-1-922027-47-4

Plant of the Month: Jan. 2017

The Sea Nymph — Amphibolis antarctica a seagrass only found in the cooler ocean waters of Australia

The Park of the Month January 2017 was Encounter Marine Park

Sea-nymph, Amphibolis antarctica, South Australia in foreground. Photo: KJ van Dijk.

Our plant of the month for January, the ‘sea nymph’, Amphibolis antarctica, is an Australian endemic species of seagrass which typically occurs in cooler temperate oceanic waters. The earliest collections of Amphibolis antarctica are likely to have been made on the Baudin expedition which were then used by P. Labillardière in 1807 to describe the new species. Plants of the genus Amphibolis are characterised by having a cluster of leaves at the end of sinuous, wirey stems.

Amphibolis antarctica is often found growing attached to rocky or harder substrates, the rhizome and root mat helping them attach by growing into crevices and enabling plants to cling to locations where other seagrasses might become detached. For this reason, Amphibolis antarctica is associated with rocky reefs, limestone and granitic underwater reefs. Amphibolis plants create a significant 3 dimensional surface area for other plants and animals to use as their home and these epiphytes and epifauna are often very obvious elements of local communities.

There have been declines in areas of Amphibolis antarctica and its sister species Amphibolis griffithii closer to the Adelaide Metropolitan region historically, and some areas on Kangaroo Island. The declines have been shown to be due to poor water quality.

Amphibolis plants produce unusual seeds – they in fact form seedlings which remain attached to the mother plant for months after they are formed and then detach and float away to settle as seedlings. This allows them to travel long distances and gives the seedlings of the sea-nymph a better start in life. Research in partnership between the State Herbarium, the University of Adelaide and Murdoch University is studying how genetically diverse populations are and how far the seedlings might travel. A field guide is available that explains more information on Southern Temperate Seagrasses including the sea-nymph.

The Encounter Marine Park is covers 3,119 square kilometres of the Gulf St Vincent and Coorong Marine Bioregions and extends from southern metropolitan Adelaide waters around the Fleurieu Peninsula and past the Murray Mouth to the Coorong coast. A baseline report on the Encounter Marine Park published last year summarised our knowledge of the reserve.

This Encounter Marine Park region contains some very large areas of seagrass and supports numerous fisheries species and other species of conservation value such as the Leafy Sea Dragon. In fact, the density of leafy sea-dragons was surveyed by divers using photo-identification methods near West Island, with density estimated at 57 per hectare (see baseline report on EnviroData SA).

Plant of the Month: Jan. 2016

The State Herbarium has chosen Posidonia sinuosa Cambridge & J.Kuo. as the plant of the month for January, 2016 and it is found the Encounter Bay Marine Park.

Posidonia sinuosa is a species of seagrass that is endemic to southern Australia and does not occur further East than the SE of South Australia. It forms very dense, stable meadows, however this species of seagrass has been listed as Vulnerable to extinction on the IUCN Redlist due to its slow growth rates, infrequent recruitment and highly fragmented habitat across its range. Posidonia sinuosa plants have very long leaves and dense rhizome mats, and as a result the meadows form important habitat for many animals and marine algae which use the plants as a home base. This species of seagrass is typically found in the relatively protected areas of South Australian waters up to around 20 m in depth. Posidonia sinuosa forms floating fruits in summer and along with the fruits of other species of Posidonia, may be often found littered along the beaches at certain times of the year.

Posidonia_sinuosa_Yankalilla_(S_Bryars)

Posidonia sinuosa meadow in Yankalilla Bay. © photo by Simon Bryars

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Global Plants, Panamá 2014

¡Bienvenidos a Panamá! — Welcome to Panamá!

GPi2014This week, some 150 delegates from around the world converged on Panama City to discuss the Global Plants Initiative (GPI).

Global Plants started as a mechanism to faciliatate access to African type specimens for the African botanical community—the African Plant Initiative—this was then expanded to include the Latin American Plants Initiative to capture Central and South American type specimens. We now have the lofty goal of imaging all vascular plant type specimens.

Michelle Waycott (Chief Botanist) and Ainsley Calladine (GPI project manager) of AD are attending, along with a number of other Australian herbarium staff involved with the GPI project.

The current Chair of the GPI Steering Committee is Australian Prof David Cantrill, Chief Botanist and Director, National Herbarium of Victoria (MEL). In his opening presentation, David outlined the progress made since the last Global Plants meeting in January 2013. The partnership currently includes 330 herbaria from 74 countries contributing more than 2.1 million objects now archived and delivered by JSTOR—this represents an amazing coordinated effort. Continue reading