Non-Sporulating

These are organisms that have not sporulated under the culture conditions provided. Most never sporulate in culture (sterile mycelia). Some represent non-sporulating colonies of common fungi (e.g., Cladosporium, Alternaria, even Aspergillus).

Characteristics

Distribution

Ubiquitous.

Where Found

See "Other Comments."

Mode of Dissemination

See "Other Comments."

Growth Indoors

Growth on a variety of substrates. Identification is not possible without sporulation.

Industrial Uses

Not applicable.

Other Comments

Potentially, all fungi are capable of producing a non-sporulating state.

Potential Health Effects

Allergens

See "Other comments."

Potential Opportunist or Pathogen

Not applicable.

Potential Toxin Production

Not applicable.

Laboratory Notes

Growth/Culture Characteristics

Many fungi do not adapt well to routine mycologic media and growth conditions and therefore, may not sporulate. Specialized media, light-dark cycles, UV light, and low or high temperatures may be required to stimulate sporulation. Unless distinctive spore types are formed, identification may not be possible. Frequently non-sporulating colonies are produced by basidiomycetes (mushrooms) which usually do not produce fruiting structures on lab media. They may produce clamp connections and/or arthroconidia within their mycelia.

Spore Trap Recognition

Hyphal fragments are not routinely counted or reported. If numbers are excessive a comment indicating high numbers of hyphal fragments will appear on the report.

Tape Lift Recognition

Non-sporulating mycelia may appear as colorless or pigmented (brown), septate (with cross-walls) or non-septate. Further identification requires sporulation.