An ascus is the sexual spore-bearing cell produced in ascomycete fungi. Each ascus usually contains eight ascospores, produced by meiosis followed, in most species, by a mitotic cell division. However
Asci of Morchella elata, Phase contrast image
There are eight ascospores in each ascus of Sordaria fimicola.
Asci of Hypomyces chrysospermus (they are unitunicate-inoperculate). DIC image.
The Ascomycota are a phylum in the kingdom Fungi that, together with the Basidiomycota, form the subkingdom Dikarya. Members of Ascomycota are commonly known as the sac fungi or ascomycetes. It is the
A member of the genus Ophiocordyceps which is parasitic on arthropods. Note the elongated stromata. Species unknown, perhaps Ophiocordyceps caloceroides.
The "candlesnuff fungus" in its asexual state, Xylaria hypoxylon
The ascocarp of a morel contains numerous apothecia.