Fungus commonly known as sac fungi or ascomycetes, constitute the largest taxonomic group within the Eumycota. These fungi form meiotic spores called ascospores, which are enclosed in a special sac-like structure called an ascus. This phylum includes morels, a few mushrooms and truffles, unicellular yeasts (e.g., of the genera "Saccharomyces", "Kluyveromyces", "Pichia", and "Candida"), and many filamentous fungi living as saprotrophs, parasites, and mutualistic symbionts (e.g. lichens). Prominent and important genera of filamentous ascomycetes include "Aspergillus", "Penicillium", "Fusarium", and "Claviceps". Many ascomycete species have only been observed undergoing asexual reproduction (called anamorphic species), but analysis of molecular data has often been
Parasites in fiction their parasitism and their swarming behaviour. Such films, she continues, depict the war of culture and nature as "an unending combat between humanity and insect-like extraterrestrial species that tend to parasitize human beings in order to reproduce." The range of accounts of fictional parasites and the media used to describe them have greatly increased since the nineteenth century, spanning among other things literary novels, science fiction novels and films, horror films, and video games. The table illustrates the variety of themes and approaches that have become possible. Kyle Munkittrick, on the "Discover" magazine website, writes that the great majority of