Thermally dimorphic fungus

Dimorphic (two forms) fungi are fungi that can reproduce as either a mycelial or a yeast-like state. Generally the mycelial saprophytic form grows at 25c, and the yeast-like pathogenic form at 37c. Dimorphism is extremely important in the identification of mycoses, as it makes rapid identification of many pathogenic organisms possible. Some diseases caused by dimorphic fungi are
 * sporotrichosis
 * blastomycosis
 * histoplasmosis
 * coccidioidomycosis
 * paracoccidioidomycosis

http://microbiology.mtsinai.on.ca/mig/difungi/index.shtml

http://pathmicro.med.sc.edu/mycology/mycology-6.htm

http://www.gsbs.utmb.edu/microbook/intomyco.htm