World Taxonomist Appreciation Day!

From Buzz Hoot Roar.

World Taxonomist Appreciation Day, March 19, was created in 2013 to make a point that the work of the world’s biological taxonomists was largely unappreciated, even though it underpins our fundamental understanding of the diversity of life (click for two portraits of Museum taxonomists from Victoria and Western Australia).

Why does this matter and what does it mean for the State Herbarium of South Australia?

In case you’re not even sure what taxonomy is and why it is a core part of the Herbarium’s role: taxonomy is the practice and science of classification (taxonomy really began as a science in the 18th century, with the Swedish botanist Carl Linnaeus, whose naming system is still used).

Linnaeus’ SPECIES PLANTARUM (1753) is the starting point of botanical nomenclature.

For biologists, taxonomy means the classification and naming of organisms in an ordered system that is intended to indicate natural relationships, and especially evolutionary relationships. This process uses a combination of the form, shape and structure of an organism (its morphology), and behavioural, genetic and biochemical observations. Taxonomic scientists follow rules that govern this process to ensure that their work is able to be adopted anywhere in the world.

Herbarium taxonomists also seek to meet high scientific standards and use an evidence base that can be built upon in the future. They work to develop identification keys which can be reliably used by others and come to the same conclusion (which means the identification of a unique organism).

The different kinds of animals, fungi, plants and microorganisms are referred to as ‘species’. A species is often defined as a potentially interbreeding group of organisms that can produce viable offspring. This may be because the two different species cannot interbreed and produce viable offspring or that they live so far apart they cannot either.

Caloplaca aggregata, a new species of lichen from Kangaroo Island, described in 2016. Photo: G. Kantvilas.

Taxonomists provide unique names for species that allow us to study them in more detail and ensure that we are all recognising the same thing. To describe a new species to science,  taxonomists first sort specimens into separate sets they believe represent potential species. Once the specimens are sorted the next job is to see whether or not they already have names. This may involve working through identification guides, reading descriptions written perhaps 200 years ago, and borrowing named specimens from museums or herbaria to compare with the sample. Such comparison may involve external characters, the need to dissect internal structures, or even molecular analysis of the DNA. If there is no match, the specimens may represent a new species, not previously given a name. The taxonomist then has to write a description, including ways in which the new species can be distinguished from others, and make up a name for it, in a Latin format. The name and the description must then be properly published so that other taxonomists can see what has been done, and be able to identify the species themselves. From finding the specimens to the name appearing in print can take many years!

Specimen boxes in the vaults of the State Herbarium of South Australia.

Comprehensive collections of identified specimens and their collection information, curated in perpetuity by museums (for animals) and herbaria (for plants, fungi and lichens), form the evidence for the identity and occurrence of each species. The ‘type specimen’ is particularly valuable as it represents the actual specimen used as the reference for a new species name.  Interestingly, most new species are not discovered in the field, but during the painstaking process of examining already collected material in herbaria and museums.

The type specimen of Spyridium parvifolium, from the Herbarium of the Royal Botanic Gardens Kew, London.

Global literature shows about 1.1 to 1.5 million described species, with estimates for the total number of species in the world ranging from 5 to 10 million. With all that taxonomic work to be done, it may come as a surprise to learn that taxonomists themselves are endangered (see also Wägele et al. 2011). In Australia, we know we are losing taxonomists at the rate of two to three per year, and the workforce is definitely ageing (as a local example, the average age of the State Herbarium’s taxonomists is 60 years and most of them are volunteers). Worldwide, we are unarguably well shy of the effort needed to catalogue Earth. It has been estimated that to discover and describe all species would take 300,000 taxonomists some 1,200 years, at a cost of more than $350bn. And this is a conservative estimate.

We are deep in a taxonomic crisis. Our own species created the planet’s sixth major extinction event (see also Hance 2015) and we are lacking the expertise to understand what we are rapidly losing. Taxonomic work is the foundation for understanding how to save what we can and make plans for the future. Any fix to the taxonomic crisis requires a recognition of the essential nature of the work of taxonomists, the value of the herbarium and museum collections and those who use them to explain our world.

Do we need to describe everything? With extinction running at 100–1,000 times what is called the ‘natural rate’, you could argue that we are fighting a losing battle and should cut our losses. But if we are to direct our limited resources into conserving the most important parts of our biological diversity, how do we know which species and systems are the most important? Taxonomy is the first big step in that process.

Solanum osteocarpum from Central Australia, newly described in 2016.

In Australia, we have an immense job ahead of us documenting life on our 7,000,000+ square kilometre continent, where more than three-quarters of the native plants and animals are found nowhere else on Earth. In just over 200 years, we have described about a quarter of the estimated half a million or so species. Are there new sources of food, medicine or building materials out there? Of course. Which species can we afford to lose if life as we know it, and pertinently human life, is to continue? What relatives of crop plants will help us survive climate change? How many and which plants do we need to produce oxygen for us to breathe?

Taxonomy is critical for almost everything we do in biology, and as a community, we need to support taxonomy and its practitioners – if not to make our life better, then because our life depends on it.

Contributed by Peter Canty, Manager, State Herbarium

A new blog for taxonomists

noto|biotica is a recently established blog that provides a community platform for the Australasian taxonomy and systematics community. Registered members can use the web-site to “update […] colleagues […] on projects, news, views, triumphs and disasters, the highs and lows of life as a taxonomist or biosystematist in Australasia, and considered insights on life in all its glory”.

So have a look, register if you are an active botanist, mycologist, phycologist, zoologist or palaeontologist, and maybe write a contribution or two.  We are looking forward to read more…

Herbarium visitor

During the next two weeks, Philipp Hühn from the University of Mainz, Germany, is visiting the State Herbarium of South Australia. He is interested in Camphorosmoideae, a subfamily of Chenopodiaceae (treated as Amaranthaceae in the APG system, but accepted as a separate family in Australia). Genera of Camphorosmoideae are distributed mainly in Australia (12 genera, c. 150 species), the most well-known are Enchylaena R.Br., Maireana Moq. and Sclerolaena R.Br. Philipp will be examining specimens for his thesis, supervised by Gudrun Kadereit, and sampling our Herbarium for molecular analyses of the group. Quite a task with over 18,000 specimens in the collection! — Welcome Philip.

Flora treatments for Chenopodiaceae are available online for South Australia (new 5th edition, 17mb pdf), New South Wales (PlantNET), Victoria (VicFlora) and Australia (1984, 24mb pdf). In Tasmania, the family is treated as Amaranthaceae (390kb pdf).

Maireana campanulata. Photo: Seed Conservation Centre, Botanic Gardens & State Herbarium.

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).