The species Circinotrichum olivaceum (Speg.) Piroz shown setae erect, circinate, unbranched, verrucose, conidiophores micronematous, flexuous, subhyaline to pale brown, smooth, conidiogenous cells polyblastic, discrete, percurrent, obc1avate to lageniform, colourless and conidia forming a whitish layer at the base of setae, cylindrical to fusiform, straight or slightly curved, aseptate, hyaline, smooth (Pironzynski, 1962; Ellis, 1971).
The species Circinotrichum olivaceum is considered of subspontaneous distribution, not endemic, being found mainly in humid forest leaf litter, this species as well as the others in the group of conidial fungi, are considered important in the decomposition of the leaves. Thus, the environmental impact reduces the vegetation and consequently the production of organic matter, which can lead to a dastic reduction of this species.
Distribution: subtropical and tropical regions
Currently the genus comprises 21 species. The species Circinotrichum olivaceum is commun in the tropic and leaf litter in the floor forest (Pirozynski 1962, Sutton 1980, Mercado-Sierra 1984, Grandi; Silva 2006), there is also record in aquatic environment, in Australia (Hyde 1997).
Population Trend: Uncertain
This species is collected associated with leaf litter.
There is no reports of this species in the deserts and Antarctica in the world. In Brazil, there are no records in the cerrado, rupestrian fields, ecosystems associated with the Atlantic rainforest such as tableland, sandbanks and mangroves.