The Ascomycota, originally the Ascomycetae, or Ascomycetes, is a division of the fungi whose members are generally referred to as the Sac Fungi and which produces spores in a particular kind of microscopic sporangium known as an ascus.
They are fungi that create tiny spores inside distinct, elongated cells or sacs called "asci," which are what give the group its name. "Spore shooters" are ascomycetes.
The Ascomycota's primary mode of propagation, asexual reproduction, is what drives these fungi's quick dispersal into new environments.