FUNGAL ECOLOGY
(sometimes with special regard to macromycetes)
Fungi and their environment • Life strategies and interactions of fungi • Ecological groups of
fungi, saprotrophs (terrestrial fungi, litter and plant debris, wood substrate, etc.) • Fungal
symbioses (ectomycorrhiza, endomycorrhiza, endophytism, lichenism, bacteria, animal relationships)
• Parasitism (parasites of animals and fungi, phytopathogenic fungi, types of parasitic relations)
• Fungi in various habitats (coniferous forests, broadleaf forests, birch stands and non-forest
habitats, fungal communities)
• Fungal dispersal and distribution • Threat and protection of fungi
(the study material has not been corrected by native speaker)
PF_72_100_grey_tr ubz_cz_black_transparent
MASARYK UNIVERSITY, FACULTY OF SCIENCE
DEPARTMENT OF BOTANY AND ZOOLOGY

PARASITISM, PATHOGENIC FUNGI
ZOOPATHOGENIC FUNGI
Fungal parasites of animals belong mainly to ascomycetes or imperfect fungi (however, two
basidiomycetes have also been found in humans – Schizophyllum commune isolated from the nails,
palate and respiratory tract, and mycelium of Coprinus cinereus in the heart membrane). They cause
either superficial dermatomycoses on the skin or mucous membranes (most of them) or systemic
mycoses affecting the internal organs. For successful attack of the host organism, it is usually
necessary to pass through the epidermis or chitin cuticle and inside the host body to cope with
response of the immune system, lack of oxygen, to buffer pH, ...
Recently, the number of cases of human mycoses in has been increasing – possible reasons are weaker
human immunity, too frequent antibiotic treatment (it suppresses all bacterial biota => easier
invasion of the fungal pathogen), or expansion of travel (transmission of fungi from other regions)
– but it is difficult to determine one factor, it is always an interplay of several factors.

Trichophyton_rubrum C:\Documents and
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Dermatomycoses are usually more
unpleasant than dangerous, but often
they go into a chronic stage.
Skin parasites are most often species
of the genera Microsporum, Tricho-
phyton, Epidermophyton (ascomycete anamorphs), usually different species
on different animals (however, it does
not exclude that „animal“ species can
be transmitted to humans).
They parasitise on keratin structures
– skin and its derivatives, nails, hair, etc., and animal hairs, feathers, horns; some fungi are
specialised only in this so-called „hard keratin“ (apparently they are eliminated by the presence
of antifungal factor in living tissues).
The mycelium grows along the dead cell layers and spreads by disintegration of the hyphae – by
formation of arthrospores (in this vegetative state the fungi are indeterminable, they can be
identi-fied by cultivation) => then they spread on skin fragments (in clothrooms, showers, etc.).
Trichophyton rubrum,
symptom in the beard and hyphae + conidia
C:\Documents and
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http://www.denstoredanske.dk/@api/deki/files/12561
Micro-sporum canis,
symptoms (infection from an infected cat) and macro-conidia

Under suitable conditions (for example, if the skin is wet for a long time; this typically occurs
in wet and moist conditions between the fingers, where the skin is both thin and sensitive),
certain species may switch to direct parasitism on living cells. Inflammatory reactions are caused
by immune response of the body to fungal metabolites.
If cracks appear in the skin => exposure of living cells, it is an ideal „gate“ for secondary
infections
– e.g. species of the genus Sporothrix, dimorphic fungi that penetrate small wounds and cause
sub-cuticular infections, but can change from hyphal to yeast-like form and be spread by the
lymphatic system further in the body => invasion of internal organs. Secondary infections are
usually a matter of facultative pathogens (these species are otherwise soil saprotrophs living on
plant remnants with teleomorphs in the genus Ophiostoma).
Sometimes it can be confused with a more serious disease – „tinea nigra“ caused by Hortaea
werneckii (anamorph of Capnodiales, Dothideo-mycetes) has a similar symptom as skin cancer.
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Sporothrix sp., top: hyphae with conidia, bottom: yeast form
http://www.doctorfungus.org/thefungi/Sporothrix.php
Symptom of
„tinea nigra“
Source: Hall & Perry 1998; also available at http://bibmed.ucla.edu.ve/edocs_bmucla
/MaterialDidactico/microbiologia
/software%20educativo/hongosnoderma.htm

Systemic mycoses are caused by both specialized and facultative (opportunistic) parasites.
The real specialized pathogens are anamorphs of fungi of the order Onygenales, causing skin and
lung diseases – Histoplasma, Blastomyces (teleomorphs in the genera Ajellomyces, Gymnoascus),
Coccidioides and Paracoccidioides.
The centers of their occurrence are in the American continents, but even after a short stay there
it is possible to become infected, just inhale spores (the risk of infection is a problem mainly
for people from areas where these fungi do not occur naturally, while „natives“ often have
developed natural immunity).
Primarily, these fungi attack the lungs (these are also the main „gateway“ to infect the body), but
in yeast form (they are also dimorphic fungi) they spread through the bloodstream to other organs.
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Histoplasma capsulatum, macroconidia and microconidia
http://mycology.adelaide.edu.au
/Fungal_Descriptions
/Dimorphic_Pathogens/Histoplasma/
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yeast_cells.gif
Paracoccidioides brasiliensis, budding yeast cells
http://mycology.adelaide.edu.au/Fungal_Descriptions/Dimorphic_Pathogens/Paracoccidioides/

Opportunistic mycoses are caused by many normally saprotrophic fungi when they attack weakened or
damaged tissues or organs.
Mucormycoses (species of the genera Mucor, Rhizopus, Absidia) or aspergilloses (species of the
genus Aspergillus, for example A. fumigatus) of the digestive tract, lungs or parts of the head may
be serious. Weakening of the organism is often a major cause – in 2021 there was a mass spread of
mucormycosis among covid patients in India.
Cryptococcus neoformans (anamorph of the basidiomycete Filobasidiella) attacks the skin and mucous
membranes, bones, lungs and nervous system; it often occurs in domestic animals (especially
ungulates), and pigeons can act as vectors in cities (spreading spores in their excrements => then
by wind).
15_filobasidiella_bazidiospory 15_cryptococcus_neoformans_bunky_v_mozkove_tkani
http://www.medmicro.wisc.edu/resources/imagelib/mycology/images/HE_c_neoformans_brain.html
Cryptococcus neoformans, cells in brain tissue
http://www.mycology.adelaide.edu.au/Fungal_Descriptions/Yeasts/Cryptococcus/C_neoformans.html
Filobasidiella neoformans, basidiospores

Saprotrophic yeast stage, parasitic filamentous form.
The most common infection is caused by the yeast Candida albicans, normally living on the surface
and inside the body (i.e. in both aerobic and anerobic conditions) – the saprotrophic stage is
yeast-like, spreads via blastospores.
If Candida has good conditions for multiplication (antibiotics, especially with a „wide range“,
14_candida_bile_skvrny_na_ledvinach 14_candida_ve_streve
Candida albicans on intestine walls and kidney surface (white spots).
http://www.candidablog.com
/what-are-male-yeast-infections.php
http://www.digitalapoptosis.com/archives/science/Candida.jpg
candida_kvasinka+vlaknita
fungi, elimination of competition for nutrients), it turns into a parasitic pseudomycelial form =>
when it enters the blood, it is spread throughout the body and often causes lingering diseases of
skin, lungs or digestive system.
can have a negative effect when they reduce the bacterial biota => free niche for

In general, mycoses of the internal organs break out more easily when the immune system is weakened
– due to a birth defect, another disease (the immediate cause of death in AIDS patients is often
candidiasis, to a lesser extent aspergillosis or mucormycosis) or medication, typically after
transplants (due to this reason the mycoses are a serious problem today, while not so much in the
past).
Fungicide compounds that deactivate the plasma membrane of fungal cells are tested against fungal
pathogens (polyenes produced by Streptomyces bind to ergosterol that is part of the membranes =>
they become permeable; synthetic azoles directly block the formation of sterols). In general, there
are a number of fungicides, but only a very limited number of them can be applied in medicine
(so as not to damage animal tissues); griseofulvin, for example, is used to treat mycoses. However,
the fungal infection is often not completely cured and returns repeatedly.

The spores of some fungi act as allergens (similar to dust, pollen, etc.) – asthma can be a
manifestation of such an allergy.
An example is aspergillosis (Aspergillus flavus, A. niger – common soil saprotrophs), which is
rather an allergic manifestation when inhaling a large number of spores => hyphae grow in organs
(especially the lungs), but aflatoxins are not produced here.
Aspergillus fumigatus belongs to the species involved at high temperatures in the process of
composting (see the chapter Saprotrophs) => allergenic action of spores in larger quantities is a
problem of people working with compost or silage.
Other common saprotrophs on plants are species of the genera Cladosporium (more in colder and
wetter areas) and Alternaria (even in warm arid areas) – their spores are released in large
quantities at harvest, which is a problem in agricultural regions.
Last but not least, we cannot forget the allergenic effect of a large number of spores in the
process of mushroom growing (in growing halls of button mushrooms, oyster mushrooms, etc.).
The general principle that outbreak of the disease is easier with weakened immunity applies
similarly to allergies, which even may not break out in a healthy person (a strong immune system
makes it easier to eliminate the fungus).

them a competitive advantage in its absence. On the other hand, they are not directly dependent on
the animal source of nutrients – they can thus affect the abundance of nematode populations, but
they are not limited by their deficiency.
From nematodes, which often form the most numerous and species-rich group of soil invertebrates in
soil, litter and rotting wood, they obtain nutrients in two ways:
The first is passive, the hypha sticks to the nematode => an appressorium is formed and then the
digestive hyphae. Adhesion is due to touch of the nematode, which stimulates the secretion of a
sticky drop containing lectins (surface proteins), which bind to the substances contained in the
cuticle. (These proteins may be specific, for example Arthrobotrys ellipsospora produces
mucopolysaccharide sensitive substances, while proteins of Arthrobotrys oligospora bind to
N-acetylgalactosamine when the nematode cuticle contains galactose. In addition to them, however,
non-specific adhesive substances are also formed, which bind to some carbohydrate chains – instead
of nematodes, for example yeasts can be caught and trapping sites blocked.)
http://helios.bto.ed.ac.uk/bto/microbes/chytrid.htm
Fungi infesting nematodes are only rarely typical parasites, such as Catenaria anguillulae
(Blastocladiomycota).
Source: George Barron, http://www.uoguelph.ca/~gbarron/2008/catenar0.htm
Most nematophagous fungi (especially imperfect) are in principle saprotrophs, which thus
„supplement their diet“ with a source of nitrogen; gain from animal tissue also gives
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zoospores enter the body orifices
hypha grows in the nematode body
the hyphal cells form sporangia and release zoospores

For example, species of the genera Arthrobotrys or Dactylaria form a mycelial loop (sometimes they
also produce substances that attract the prey) => when the nematode enters the loop, the fungal
cells „inflate“ and pinch the prey => then digestive hyphae absorb nutrients from its body. Another
way of „hunting“ is applied by some Pleurotaceae (anamorphs of Hohenbuehelia or Resupinatus
species), which do not form loops, but trap nematodes in wood by outgrowths with sticky matter =>
after gluing the nematode they excrete a substance that immobilises it => mycelium grows into the
body cavity. (Also some other fungi can spontaneously „feed“ on nematodes immobilised by the
excreted toxins or narcotics.)
/More about various types of trapping structures see in General mycology, chapter Vegetative
thallus of fungi, section Specialised cells and hyphal structures./
Trapping structures are in some cases produced spontaneously (we can also find them in pure
culture), while in other cases they are formed only if the prey is present (i.e. after chemical
induction).
The second way is active „hunting“ – the fungi behave as predators (referred to as „predatory
fungi“), applying various types of baits, snares, nets and trapping structures.
21_lovi_lasem constric
Drechslerella anchonia
http://www.masozravky.com/rody/drave_houby/arthroba.htm
Dactylaria brochopaga

Some species of fungi are completely „indiscriminate“ (in terms of prey, e.g. Zoophagus
pectosporus), while others specifically hunt, for example, members of a specific family of
nematodes (Monacrosporium ellipsosporum).
It should be added that the „hunter-prey“ relationship is not only one-way between fungi and
nematodes – many soil nematodes can suck hyphae and thus negatively affect, for example,
communities of ectomycorrhizal fungi.
Zoophagus
Source: Cooke & Whipps 1993;
taken from http://botany.natur.cuni.cz
/koukol/ekologiehub/EkoHub_6.ppt

Representatives of „water moulds" of the order Saprolegniales (Peronosporo-mycota) are important
parasites of aquatic animals, especially fish; Saprolegnia parasitica (photo on the left) is a
natural inhabitant of our waters, but increased occurrence in fish farms (in ponds or in aquariums)
is a serious problem.
Other species of this group parasitise invertebrates; Aphanomyces astaci (introduced from the USA
to Europe; photo on the right) destroys the local populations of crayfish.
Saprolegnia_fish_2
Photo: Andrzej Martin Kasiński, http://www.nurkomania.pl/fauna_raki.htm,
resp. http://www.nurkomania.pl/atlas/n285.jpg
Astacus
West 2006; taken from http://botany.natur.cuni.cz/koukol/ekologiehub/EkoHub_6.ppt

Currently the most dangerous fungus, spreading in the aquatic environment, is probably
Batracho-chytrium dendrobatidis (Chytridiomycota).
It is not known where it comes from (human transport has a great influence on its spread, warming
may have a certain effect too), but it is responsible for the global problem of the decline of
amphibians.
Source: Davidson et al. 2003; taken from
http://botany.natur.cuni.cz/koukol/ekologiehub/EkoHub_3.ppt
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http://tropicalis.berkeley.edu
/home/husbandry/disease.html

The most frequent are insect parasites (they are also probably best known for their use in
biological control, although bacteria or viruses are used more effectively – the success of fungal
infection is more dependent on environmental conditions that allow spores to germinate). They are
usually specialised in a certain stage of insect development – larvae and pupae are attacked mainly
by soil species, while parasites of imagines spread through the air.
Fungi of the genus Entomophthora infect the insects by mucous conidia => they germinate, forming
mycelium with apressorium => the hyphae penetrate the body (the skeleton is enzymatically
disrupted) => inside they break down into hyphal bodies (single- or multicellular fragments) =>
they are spread by hemolymph throughout the body => further division => conidiophores and conidia
are formed
C:\user\Houba\Škola-www\stazeno\ekolhub_parazit\23_Entomopthora_muscae.jpg
http://www.uoguelph.ca/~gbarron/MISCELLANEOUS/ento2.htm
from hyphae growing on the body surface => they are thrown away and can spread to other
individuals. Entomophthora muscae (see photo) parasitizes on flies, related species Entomophthora
grylli attacks locusts and can decimate entire populations in wet weather.
Entomophthorales (in addition to obligate parasites, recent subdivision Entomophthoromycotina of
the zygomycete lineage Zoopagomycota includes also saprotrophs) are mainly temperate fungi; some
species kill insects quickly (within a few days), others are „gentle“, the infested insect survives
and is a carrier that spreads the released spores.

Species of the genus Cordyceps sensu lato (order Hypocreales) commonly parasitize on larvae, pupae
and adults of various insects, especially in the tropics (but many species grow in our country, for
example Cordyceps militaris can be important in regulating populations of some parasitic insect
species). The affected body is grown through and „mummified“ => a pseudosclerotium is formed (often
in the soil, a persistent stage), from which stromata subsequently grow. Cordyceps species are
favourite food of some animals (e.g. deer eat them with mummified insects) and humans (a delicacy
in China or Australia).
26_Housenice_Strevlikova_s_kuklou 25_Housenice_Strevlikova
From left to right: Cordyceps militaris, two photos of C. entomorhiza growing from the pupa,
top right C. dipterigena on the fly, bottom C. lloydii on the ant of the genus Camponotus.
Photo (2x) Míla Dobešová, http://www.idsystem.cz
/mushrooms
/miladobesova.htm
Cordyceps_fly
Foto (2x) L. Gilbert, http://www.utexas.edu/courses
/zoo384l/sirena/species/fungi/
Cordyceps 25_cordyceps-militaris_maros-margetin
Photo Maroš Margetín, http://www.nahuby.sk
/obrazok_detail.php?
obrazok_id=135514

Do you want to be like Sam Pakonen?
C:\user\Houba\Škola-www\stazeno\ekolhub_parazit\28_cordyceps_sinensis_reklama.jpg
Let’s eat Ophiocordyceps sinensis!

Many entomopathogenic species (at least hundreds) belong to imperfect fungi (Beauveria,
Metarhizium; some are facultatively parasitic): the spores germinate on the body surface and the
fungus penetrates inwards (similarly to Entomophthora), spreading through hemolymph like yeast
cells (some producing toxins) => after death of the insect it goes back to the hyphal form and
grows through the body.
Larvae of dipterans are attacked by Coelomomyces (Blasto-
cladiales) – it is applied against mosquitoes in the tropics.
The same fungal species can be a symbiont for one organism and a pathogen for another – an example
is the yeast Rhodotorula glutinis, which probably lives symbiotically in the frog intestines => if
excrement with this yeast is released into the water (likely even release of its metabolites is
sufficient), it has decimating effect on the larvae of female mosquitoes (higher mortality, some do
not pupate, hatched imaga are smaller – why it affects only females remains a question).
C:\user\Houba\Škola-www\stazeno\ekolhub_parazit\24_coelomomyces_hyfova_teliska_v_hemolymfe.jpg
Left: Beauveria bassiana growing out between body segments of Pantorhytes plutus.
Right: Coelomomyces sp., hyphal bodies in hemolymph of Dicrotendipes californicus.
C:\user\Houba\Škola-www\stazeno\ekolhub_vyuziti\52_beauveria_bassiana_on_pantorhytes_plutus.jpg
http://www.dropdata.org/cocoa/cocoa_biological.htm
Photo J. Robert Harkrider, http://empidid.com/NatEm/coelomom.html

Perhaps parasites and perhaps also commensals are also fungi formerly classified in the class
Trichomycetes (orders Harpellales and Asellariales, zygomycetes now also belonging to
Zoopagomycota, subdivision Kickxellomycotina), growing in the intestines of arthropods. It is also
a matter of concept – whether a parasite is, in principle, any organism that removes nutrients from
its host, or whether it is commensalism if the host is not visibly damaged; in the case of
Trichomycetes, it has not been proven to what extent these fungi diminish the nutrition of their
host.
plate by Alex Weir
Apparently commensals (not very harmful to their hosts, at most a slight parasitism is supposed)
are Laboulbeniales, which form very specific associations (one species of this fungal group grows
only on a very limited range of related insect species). They grow on the surface of the insect
body and their haustoria penetrate surface cells of the cuticle, from where they probably take all
the nutrients – we can regard it as obligatory commensalism.
http://classes.plantpath.wsu.edu/plp521/

PARASITES OF PROTOZOA, ALGAE AND FUNGI
Many fungi parasitise on protozoa and other single-celled organisms. Species of the order
Zoopagales (Zoopagomycota) attack amoebae:
a hypha or sticky conidia sticks to the cell (the reaction of
the cell is a "dead beetle", it stops moving) => the fungus
grows inside and creates digestive hyphae in the cell.
Similarly, species of the genus Zoophagus (also Zoopagales)
attach to the rotifers.
On the other hand, we also encounter cases where fungi are
victims – predatory rhizopods of the group Vampyrellidae (divis. Cercozoa) suck the content of
hyphae (Leptomyxa reticulata) or hyphae and spores (Arachnula).
20_zoophagus_hyfa_vrostla_do_virnika Amoeb_spores
Slime mould plasmodia secrete chitinases, they can „consume“ mycelium, conidia and decompose
fruitbodies of macroscopic fungi.
Leptomyxa Arachnula
taken from http://botany.natur.cuni.cz/koukol/ekologiehub/EkoHub_6.ppt
Source:
Cooke & Whipps 1993
http://starcentral.mbl.edu/microscope
/portal.php?pagetitle=assetfactsheet
&imageid=69
Arachnula sp.
Leptomyxa reticulata
http://www.masozravky.com/rody
/drave_houby
/zoophagi.htm
Hyphal peg of Zoophagus insidans growing into the rotifer body.

Parasites of algae are mainly from the division Chytridiomycota – they are usually
difficult-to-identify organisms, mostly with eucarpic monocentric thalli and uniform zoospores.
They play an important role in the regulation of phytoplankton populations, in freshwater lakes
they can be at some stages the richest component of aquatic biocenosis.
Species of the genus Rhizophydium parasitise on diatoms, euglenids, green algae (but also on
nematodes or pollen grains), Polyphagus (both Chytridiales) also on euglenids.
C:\user\Houba\Škola-www\stazeno\ekolhub_parazit\30_rhizophydium_sporangia_na_rozsivce.jpg
Left: sporangia of Rhizophydium sp. on diatom frustule.
Right: Polyphagus euglenae – zoospore, rhizomycelium connecting infected cells, course of the
sexual process and formation of zoosporangia.
http://protist.i.hosei.ac.jp/pdb/images/Eumycota
/Rhizophydium/index.html
C:\user\Houba\Škola-www\stazeno\ekolhub_parazit\30_polyphagus_euglenae.jpg

Mycoparasitism is proving to be common in nature (up to 3,000 species para-sitising on other fungi
have been reported). There is always contact between the mycelia of the parasitic and the host
fungus based on the recognition of the host mycelium by surface lectin reactions, followed by
adherence or penetration of the host cell and biotrophic or necrotrophic nutrition. (Types of
parasitism see later.)
Biotrophic parasites usually attach their hyphae close
to the infested ones, penetrate the cell wall (they have
only chitinolytic enzymes, but not enzymes that would
kill the cell) and create haustoria inside the cell.
Most biotrophic mycoparasites belong to zygomycetes:
– Spinellus (order Mucorales) parasitise fruitbodies of
various basidiomycetes;
– many species of the order Dimargaritales parasitise
biotrophically on Mucorales (they are difficult to grow
          in culture and do not sporulate if they do not have a host),          applying positive
chemotropism to the host hyphae;
          – Piptocephalis (order Zoopagales) grows on coprophilic           saprotrophs; although
these fungi are found on faeces,          they are not coprophilous species but their parasites.
85_spinellus_fusiger Piptocephalis
Piptocephalis sp.
http://www.mycolog.com/CHAP3b.htm
Spinellus fusiger

Necrotrophic parasites can be found, for example, among yeasts. Pichia guilliermondii
(Saccharomycetales) is a necrotrophic parasite of hyphomycetes.
Once more Piptocephalis ... Source: Cooke & Whipps 1993; taken from
http://botany.natur.cuni.cz/koukol/ekologiehub/EkoHub_6.ppt
Piptocephalis2
Another group where biotrophic mycoparasites occur are Blastocladio-mycota – Catenaria allomycis
grows endo-biotically in fungal cells of the genus Allomyces (of the same division).
Among the biotrophic fungi we can find also hyperparasites (i.e. parasites of parasites), e.g.
Phoma glomerata invades powdery mildews; in contrast, the yeast Tilletiopsis has enzymes that kill
the mildews.

of the host hypha, different parasites have different specificities), hyphae of the parasite begin
to wrap around it. Trichoderma species are used in biocontrol of phytopathogenic fungi.
Important necrotrophic parasites are also among oomycetes: Pythium oligandrum attacks
endomycorrhizal fungi of the genus Glomus, zygomycetes or hyphomycetes (the „attack“ is quite
rapid, the host hypha is killed within tens of minutes and Pythium continues to grow).
Pythium C:\Documents and
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Famous necro-trophic parasites are species of the genus Trichoderma,
which penetrate the host hypha => toxins kill the cells => their contents are then decomposed. It
is preceded by thigmotropic reaction of the mycelium – upon contact with potential hypha host (it
appears to be a reaction to exudates
Trichoderma viride
Source: Cooke & Whipps 1993
taken from http://botany.natur.cuni.cz/koukol/ekologiehub/EkoHub_6.ppt
Photo Stanislav Jirásek, http://www.grzyby.pl/gatunki/Trichoderma_viride.htm

Macromycetes also have their parasites, such as Pseudoboletus parasiticus on Scleroderma,
Asterophora species on Russulaceae, Tremella species on stereoid fungi or Elaphocordyceps
ophioglossoides (Hypocreales) on Elaphomyces. In some cases (Asterophora) the fruitbodies of the
parasitic fungi are found on dead fruitbodies of the host fungi – it is then difficult to
distinguish whether they are saprotrophs or parasites (whether they have already parasitised in the
form of mycelium during the host life).
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Settings\Hrouda\Dokumenty\S_Vyuka\stazeno\ekolhub_parazit\88_xerocomus_parasiticus.jpg C:\Documents
and Settings\Hrouda\Dokumenty\S_Vyuka\stazeno\ekolhub_parazit\89_nyctalis_parasitica.jpg
C:\Documents and
Settings\Hrouda\Dokumenty\S_Vyuka\stazeno\ekolhub_parazit\91_cordyceps_ophioglossoides.jpg

Another case is the relationship between lignicolous fungi (it concerns only a few species, for
example Trametes gibbosa versus Bjerkandera spp. or Lenzites betulina versus Coriolus spp.) – the
„attacker“ looks like a „parasite“, but its main aim is to occupy the substrate which is already
occupied by the „host“ fungus.
However, species that are probably not parasites also grow on the fruit-bodies of other fungi –
examples can be found in Herpotrichiellaceae (Chaetothyriales): Capronia porothelia growing on
Laxitextum bicolor is said to be a parasite, but is it really harmful to its „host“?
http://houby.humlak.cz/big_htlm/laxitextum_bicolor_1.htm
Laxitextum_bicolor
http://myco-cheype.chez-alice.fr/classification/ascomycetes/Ascomycetes.htm
Capronia_porothelia
Laxitextum bicolor
Capronia porothelia —