Pycnidium

A pycnidium (plural pycnidia) is an asexual fruiting body produced by mitosporic fungi, for instance in the order Sphaeropsidales (Deuteromycota, Coelomycetes) or order Pleosporales (Ascomycota, Dothideomycetes). It is often spherical or inversely pearshaped (obpyriform) and its internal cavity is lined with conidiophores. When ripe, an opening generally appears at the top, through which the pycnidiospores escape.