Characteristics

Distribution
Ubiquitous;
cosmopolitan.
Monotypic.

Where Found
Soil, good stuffs, hay, textiles. Grows on salted fish.

Mode of Dissemination
Dry spore.
Wind.

Growth Indoors
Wallemia grows on relatively dry surfaces; found on wood in crawl spaces. Common in mattress dust; may colonize human skin scales.
Aw=0.69-0.75

Industrial Uses
Not known.

Other Comments
Wallemia is a keratinophilic, osmophilic fungus (grows on highly concentrated solutions e.g. salt and sugar).

Potential Health Effects

Allergens
Known allergen.
Type I allergies (hay fever, asthma).

Potential Opportunist or Pathogen
Rare human abscess reported.

Potential Toxin Production
Walleminol, tryptophol and UCA 1064-beta.

Laboratory Notes

Growth/Culture Characteristics
Poor growth on general fungal media. Grows on specialized fungal media with high osmotic pressure. Forms very small tan elevated colonies on DG18 and MEA. While an occasional colony will appear on malt agar, Wallemia may be missed when this is the only media used.

Spore Trap Recognition
Very small cubical (initially) light brown spores formed in chains of four. Recognizable when young, fresh, and when still in chains.

Tape Lift Recognition
Distinctive and identifiable on tape lifts. Observation of sporulating structures may require 1000X magnification (oil immersion).