06 • 12 • 2019
Mushrooms that Grow on Other Mushrooms
The joy and passion of mushroom picking is no stranger to the people of Latvia. Certain mushrooms are searched for, photographed and brought to the table, but mushrooms also play an important role in the nutrient cycle. The world of mushrooms includes many parasites, organisms that live in or on other living organisms and feed on their host substances. Hosts of parasitic fungi tend to be plants, animals and humans, as well as other mushrooms.
Mold mushrooms - a collection of microscopic fungi
Mycophilia (mycota - fungi + philos - love) turns out to be a common occurrence among mushrooms. It is often seen in the warm seasons of the year on the fruiting body of a basidiomycota (cap mushroom, polypore, fuzz-ball), which is overgrown with one of the oldest living organisms on our planet - the mold (Zygomycota).
Such a finding is by no means unique, as it is difficult to imagine a surface that would not be suitable for the growth of any mold. Mold mushrooms are not picky - they can inhabit almost any surface. Why would hat mushrooms be an exception?! The key requirements for mold growth and development are sufficient moisture and oxygen levels, food - carbonaceous substances - and an adequate temperature. If climatic conditions change and are no longer pleasant, the mold can “preserve itself” to await the return of more suitable conditions, for example, in the first autumn frost, it does not die but hibernates to wait for some warmer days instead.
It should be borne in mind that molds tend to be different, since they are caused by several species of microscopic fungi at the same time, so they are a combination of different species of microscopic fungi.
Hypha - the visible part of mold
Mold develops from microscopic spores that spread through the air. When the spores settle on a suitable substrate with the appropriate temperature and the required humidity, they begin to develop and, by forming a fungus or mycelium, eradicate fine filaments, called hyphas. Thickly twisted braids of these hyphae are the visible layer of the mold.
Mold is caused by a combination of different species of microscopic fungi, therefore the shape of the interwoven hyphae also varies.
The parasitic web mold (Syzygites megalocarpus) gradually becomes fluffy like cotton wool, creating and weaving its very long hypha-filaments in a chaotic web. This fluffy creature tends to inhabit the fruiting bodies of various species of agaric mushrooms and boleti. It is most often to be found on mushrooms that are starting to rot.
Parasitic fungi can be easily observed
There are also light (top white, brownish at the base) parasite fungus (Tilachidium brachiatum), a few millimetres long, which quite often and always in dense groups grows on the fruiting bodies of other mushrooms, first choosing the low-growth agaric mushrooms that are more or less decomposed.
The bolete eater (Hypomyces chrysospermus) grows on beloti; it is a parasite that specializes in the use of various boleti as their habitat. This parasitic fungus undergoes several distinct stages as it develops. At first, it looks like a small, whitish, velvety powder-molded patch on a boletus, but soon it spreads almost over the entire host's fruiting body, visually making it look like it were covered with white icing sugar. This is followed by a change of the white colour of the parasite into golden yellow and distortion of the shape of the fruiting body of the boletus. The last stage, in which the parasitic fungus turns red-brown is rarely to be seen, as the host fungus is then usually rotted and dissolved.
The green gillgobbler (Hypomyces viridis) is related to the bolete eater. It grows on a variety of agaric mushrooms, mainly on russulas, milk caps. The fruiting bodies of the mushrooms inhabited by the green gillgobbler become green on the outside, change their shape, lose their elasticity, and before decomposition, they turn into completely unrecognizable solid formations.
Toothed jelly grows on wood-degrading mushrooms
The toothed jelly is a peculiar parasite - a jelly-type, irregularly shaped fungus that can be found in our forests throughout the year, even in winter. Although they appear to grow on wood, they are, in fact, real parasites that live on other fungi, namely, wood-destroying fungi.
Toothed jellies are most often to be spotted in spring and autumn because their fruiting bodies swell mainly in cool and humid conditions. In contrast, when the humidity drops significantly, the fruiting bodies of these mushrooms dry and flatten very quickly. Dried fungus films may remain viable for a long time, waiting for favourable weather conditions. When rain is expected, they swell and regain their former jelly-like consistency, to some extent their original form.
The fruiting body of the yellow jelly fungus (Tremella mesenterica), as suggested by its name, is yellow. The brightness of the colour, however, largely depends on the wetness of the fungus: the less fluid the fruiting bodies contain, the brighter they become in colour and vice versa; therefore, in very rainy summers, the yellow jelly fungus can become more translucent. These fungi occur in Latvia throughout the year, but are most often to be observed in early spring, late autumn, and warm winters, when their fruiting bodies are sufficiently swollen in moisture. The yellow jelly fungus lives on decaying wood that has not lost its bark yet: on fallen trees, on branches of standing trees, as well as on branches lying on the ground. Relatively often, they can be seen on thin oak trees, less often on branches of other deciduous trees. Yellow jelly fungi parasitize on Peniophora mycelium. Peniophora is quite common in Latvia, but hardly noticeable.
It is possible that some Latvian mushroom watchers may be able to spot the golden ear (Tremella aurantia), which is similar to the yellow jelly fungus. Compared to the yellow jelly fungus, the body of the golden ear has a more pronounced shape of crease and a matt surface, and it can reach larger sizes. The golden ear parasitizes on the fruiting bodies of the hairy curtain crust, which is usually seen on stumps, fallen trees and other bulky pieces of wood.
Mushrooms - parasites
There is also a relatively large population of brain-like tremella encephala mushroom in Latvia, and this mushroom is usually to be seen on dead coniferous wood. Common places for lodging of this fungus are small fallen trees and branches in felling areas. It is most often to be observed in cold and wet periods of the year - early spring and late autumn. The mushroom parasitizes on wood-destroying stereum.
A common fungus is the brown coloured tremella foliacea, which can be seen on both decayed and weakened deciduous and coniferous wood, both on thin trunks, branches and stumps of standing trees. It is most often parasitic on wood-destroying stereum, less frequently on other fungi of the genus Stereum. The shape of the fruiting body of the tremella folicea, when sufficiently moist, is usually reminiscent of a crocheted, plump, thin leaf tuft, ranging in colour from yellowish (young) to dark brown (mature). As the tremella folicea dries, its fruiting bodies grow black, flatten, wrinkle and harden.
