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Taxonomic fungal category. The term "coelomycetes" refers to asexual fungi that form conidia in a cavity (pycnidia) or a mat-like cushion of hyphae (acervuli; stromata). Example: Phoma.



Recovered from a wide range of ecological niches. Approx. 700 genera.

Where Found

Saprophytic or parasitic on higher plants, other fungi, lichens, vertebrates.

Mode of Dissemination

Conidial masses may be dry or slimy.
Spread by insects, water splash, wind.

Growth Indoors

Yes, on many substrates, including ceiling tile, linoleum. May have little effect on the indoor air because in many genera the spores are not readily disseminated by air currents.

Industrial Uses

Not known.

Other Comments

These fungi are sometimes referred to as "pycnidial formers."

Potential Health Effects


Type I allergies (hay fever, asthma).
Crossreactivity is suspected between Phoma and Alternaria.

Potential Opportunist or Pathogen

Dependent on genus and species, but the vast majority do not cause disease.

Potential Toxin Production

Not known.

Laboratory Notes

Growth/Culture Characterisics

Spores are formed in pycnidia or acervuli (asexual fruiting bodies). Spores often formed in sticky masses or exuded in mucoid droplets.

Spore Trap Recognition

Most are not easily recognizable on spore trap slides. A few (e.g. Pestalotia, Pestalotiopsis) are very distinctive.

Tape Lift Recognition

Identifiable on tape lifts if the fungus present is one of the distinctive coelomycetes or if the spores and entire fruiting body are present. Pycnidia, however, do not always lift well on tape sampling; masses of very small spores found within a mat of fungal mycelia is often indicative of the presence of a coelomycete.