Ascobolus stercorarius
Krypt.-Fl. Schlesien 3.2(1–2): 56, 1893.
Common Name: none
Synonym: Ascobolus furfuraceus Pers.
For descriptions see Van Brummelen & 'California Mushrooms'.
Scattered to gregarious on cow dung; common, fruiting year-round when moisture is available, widely distributed.
Unknown. Who will test the edibility of a TINY fungus growing on cow dung?
Ascobolus stercorarius forms tiny, greenish yellow, cup- to cushion-shaped fruitbodies on cow dung. When the asci mature, they elongate and protrude above the hymenium surface, exposing their internal violet-brown spores, which causes the surface to look black-spotted. Although common, the species is usually overlooked, except by those few mushroom collectors who carefully study the surface of cow dung. If you put fresh cow dung in a container and keep it moist, you can watch the progression of the fruiting of many small and fascinating fungi.
Beug, M.W., Bessette, A.E. & Bessette, A.R. (2014). Ascomycete Fungi of North America. University of Texas Press: Austin, TX. 488 p.
Dennis, R. W. G. (1981). British Ascomycetes. J. Cramer: Vaduz, Liechtenstein. 585 p.
Desjardin, D.E., Wood, M.G. & Stevens, F.A. (2015). California Mushrooms: The Comprehensive Identification Guide. Timber Press: Portland, OR. 560 p.
Doveri, F. (2004). Fungi Fimicoli Italici. Associazione Micologica Bresadola: Trento, Italy. 1104 p.
Van Brummelen, J. (1967). A world monograph of the genera Ascobolus and Saccobolus (Ascomycetes, Pezizales). Rijksherbarium: Leiden, The Netherlands. 260 p. (PDF)