Friday, December 2, 2016

SPEAKER’S REPORT: November 2016

Dr Tony Young was a fluent and entertaining speaker on the topic “The Rotten World Around Us”. He has had a varied career, in teaching and in the Navy, and has studied continually to gain a Masters degree and PhD in the field of Mycological Taxonomy. He says “Don’t take the Rotten World for granted – fungi form the foundation for the world’s ecosystems. Without them we would not survive.” There are an estimated 25,000 macrofungal species in Australia, with only 8,000 to 10,000 having been described and named, so it is likely that you could find an undescribed species in your fungal travels.
Tony illustrated his talk with brilliant photographs taken by himself and others, many of them being fungi which we are able to see in local areas such as Bunya Mountains National Park. Macro-fungi, those which have fruit bodies visible to the naked eye, can be roughly divided into four categories.
Saprophytes fungi which break down plant material. Some you will see sprouting from dead or living wood in forests. Examples include:
  • Filoboletus manipularis – delicate white stemmed fungi with tiny holes on the underside.
  • Cymatoderma lamellatum – a large leathery, fluted, funnel-shaped fungus with a smooth lower surface.
  • Cyptotrama aspratum – which has white gills and a yellow cap with tiny spikes.
  • Aseroe rubra – a stinkhorn fungus which grows in mulch and is shaped like a starfish. The foul-smelling brown slimy substance which contains spores is attractive to blow-flies, and to some dogs which can be poisoned by it.
  • Geastrum triplex – star-shaped with a spore sac in the centre, the spores being dispersed by raindrops falling on the sac.
  • Polyporus australiensis – a yellow curry-smelling bracket which contains a fabric dye.
  • Hebeloma aminophila – an agaric which grows on the remains of dead animals.
Parasites – fungi which parasitise plants, sometimes killing them. Some examples Tony gave:
  • Cyttaria septentrionalis – round orange-coloured fruit bodies seen on Antarctic Beech trees (Nothofagus moorei). These date back to Gondwana, can be seen in Lamington National Park in Spring, and are edible.
  • Armillaria luteobubalina – the fungus attacks the roots of trees, and can destroy whole orchards.
  • Phellinus species – the horse-shoe fungus, which forms woody growths on tree trunks, adding a layer each year.
  • Ganoderma applanatum – a large bracket fungus with a white pore surface, which is also a tree killer.
Symbionts – fungi which live in a mutually beneficial relationship on the roots of forest trees. The whole Myrtaceae family (Eucalypts and others) would die without them. The fungal hyphae wrap around the cells of the tree roots, enabling the fungus to give the tree nutrients and water and receive sugars in exchange. Examples include:
  • Amanita muscaria – the poisonous but beautiful red-capped mushroom with white spots, spreading north and having been seen in the Toowoomba area.
  • Ramaria species – soft-fleshed coral fungi of various colours. (Tony is a noted expert on coral fungi.)
Food – fungal fruit bodies are delicious not just to humans (truffles, morels and common field mushrooms), but also to other creatures.
  • Lactarius clarkeae which grow from the roots of Eucalypts are a food of the shiny black land mullet, the skink Egernia major.
  • Omphalotis nidiformis is a glow-in-the-dark soft agaric growing from dead wood, poisonous to humans but eaten by the Giant Panda snail, Hedleyella falconeri.
  • Hymenogaster species and other underground truffle-like fungi make up 90% of the food items eaten by Potoroos and Bettongs. Spores are dispersed in their droppings.
Conservation of fungi.
Fungi do not have a high profile, and Tony knows of only one place in Lane Cove National Park, NSW, which has been declared a Conservation area because of special fungi. An unpolluted gallery rainforest provides the perfect habitat for Hygrocybe species to flourish. He showed a photograph of at least 10 species in this genus which were collected in one afternoon. Hygrocybe lanecovensis, a startling red mushroom with cream gills and stem, was named after the area.
Although we think of fungi as requiring high rainfall, they also grow in deserts.
  • Podaxis pistillaris, or “Cannibal’s war club” grows in dry places.
  • Podaxis beringamensis can be seen growing from termite mounds and can be up to one metre tall. Tony showed a photograph of this large fungus taken at Maidenwell. The exact relationship of the fungus with the termites and perhaps their food storage has yet to be determined.
Micro-fungi require a microscope. Many are important in the field of medicine, such as Penicillin, Strepto-mycin and Tetracycline. Cyclosporin is a substance obtained from a micro-fungus discovered in a soil sample from Norway. It is used as an immuno-suppressant drug in organ transplants as it has very few side effects.
Fungal research is poorly funded for the following reasons:
  • Poor publicity
  • Taxonomic work is very painstaking and slow
  • Fungi are generally unknown and uninteresting to the average Australian.
Our thanks, Tony, for your interesting talk. We look forward to hearing from you again at some future date.
(Report by Glenda Walter)

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