Iryna Yatsiuk, mycologist
Department of Mycology and Plant Resistance,
V.N. Karazin Kharkiv National University, Ukraine
This year in May me and my husband Yehor Yatsiuk, ornithologist, spent a week in Dürrenstein Wilderness Area. While Yehor was involved in the Owl research project, I’m a mycologist and therefore was focused on fungi. Though for harvesting mushrooms (for food) autumn is the most appropriate season, for mycologist spring is a very nice time to discover interesting species and ecological groups.
One of such spring groups is nivicolous myxomycetes. To be exact, myxomycetes (or slime moulds) are not true fungi, being rather related to animals. They are protists, amoebae, which can aggregate and, on one stage of their living cycle, form fungi-like fruitbodies from millimetres to dozens of centimetres in size. That is why they are traditionally studied by mycologists. As amoebae, myxomycetes live in plant debris, where they feed on bacteria or other microorganisms. When the amoebae population grows and the feeding resources deplete, amoebae aggregate (crawl together) and form a huge amoeboid mass (plasmodium). Plasmodium looks like coloured slime and gives name to the whole group - slime moulds. After that, myxomycetes fructify, forming ball-like, hair-like or lollipop-like fruitbodies on dead or living wood, grass or even on the walls of buildings.
Feeding on bacteria, and being itself a food for e.g. beetles and slugs, myxomycetes provide the flow of nutrients through the ecosystems and are essential part of forest food webs.
Usually myxomycetes can be found in warm seasons of the year, especially after rains. But one group of slime moulds, more than 80 species, generally referred to as “nivicolous” or “snowbank” myxomycetes, chose specific ecological strategy. They develop their plasmodia and fruitbodies in late spring near the border of melting snow. This habitat provides special conditions. One the one hand, temperature under the melting snow is quite low (nivicolous myxomycetes are very well adapted for it), but on the other hand snow layer protects from rapid changes of temperatures. Besides that, high moisture and big amount of plant debris makes this habitat suitable for these organisms. Nivicolous species of myxomycetes are most frequently found in the mountains, particularly in the alpine belt, so the Dürrenstein Wilderness Area is a perfect place to expect high biodiversity of this amazing group.
In total, during our short stay,18 species of myxomycetes were recorded, among them 14 are nivicolous. Most of them belonged to the genus Lamproderma, whose fruitbodies shine with various shades of blue, bronze and violet.
Besides that, very abundant were bright-yellow Physarum alpestre and pure white Diderma alpinum. Their fruitbodies are covered with lime crust, which is composed of calcium carbonate.
Apart from myxomycetes, in the Wilderness area we identified 9 species of true fungi. Among them there are 4 different species of false morels (genus Gyromitra). One of discovered species, Gyromitra geogenia, has almost non-visible stipe, and in general looks like a brownish plate lying on the ground. It is the alpine species, and also is known to grow near the melting snow.
Well-preserved forests of Wilderness area, including primeval ones, provide the high biodiversity of fungi and fungi-like protists, and undoubtedly there are many more species to be discovered!