Exploitation of faecal resource units by coprophilous ascomycotina

Ability of Ascobolus viridulus, Chaetomium bostrychodes and Sordaria macrospora to produce biomass within, fruit upon, and cause degradation of rabbit faeces was followed using faecal resource units (copromes). On all three criteria, performance was in the order C. bostrychodes > S. macrospora > A. viridulus. This did not correlate with hyphal extension rates, which were in the order S. macrospora > C. bostrychodes > A. viridulus. Species mixtures produced generally higher degradation rates than those effected by single species.

In mixtures, fruiting of all species was depressed, especially that of A. viridulus. For single species, fruiting patterns appeared to be determined by the time at which sufficient resources could be allocated to reproduction rather than by hyphal extension rates.

These results are discussed in relation to current concepts of nutrient competition and resource distribution between coprophilous fungi.