Ophiocordyceps


Ophiocordyceps is a genus of fungi within the family Ophiocordycipitaceae. The widespread genus, first described scientifically by British mycologist Tom Petch in 1931, contains about 140 species that grow on insects. Anamorphic genera that correspond with Ophiocordyceps species are Hirsutella, Hymenostilbe, Isaria, Paraisaria, and Syngliocladium.
One species complex, Ophiocordyceps unilateralis, is known for its parasitism on ants, in which it alters the behavior of the ants in such a way as to propagate itself more effectively, killing the ant and then growing its fruiting bodies from the ant's head and releasing its spores.
To accomplish this, infected ants are stripped of their instinctive fear of heights, and leaving the relative safety of their nests, climb up the nearest plant—a syndrome known as "summit disease".
The ant clamps its jaws around the plant in a "death grip" and following, mycelia grow from the ant's feet and stitch them to the surface of the plant. The spores released from the ant carcass fall to the ground and infect other ants that come in contact with the spores so that this cycle continues. Areas with high densities of ants that have this fungus growing out of them are known as graveyards.
A 48-million-year-old fossil of an ant in the death-grip of Ophiocordyceps unilateralis was discovered in Germany.

Non-insect hosts

One not-yet-named fungus that falls into Ophiocordyceps infects juvenile edible crabs. Infection is fatal once the fungus becomes established in the hemocoel.

Species

Reference:
A relatively broad phylogeny of the genus was published in 2024 as part of the effort to distinguish more species from inside the O. sinensis complex.

In popular culture

Simply referred to as "cordyceps", an unspecified species in this genus is the cause of a worldwide pandemic and the zombie-like "infected" in the 2013 video game The [Last of Us (video game)|The Last of Us], its 2020 sequel, and the 2023 television adaptation.
In the 2014 novel The Girl with All the Gifts and its 2016 The Girl with All the [Gifts (film)|film adaptation], a mutation of Ophiocordyceps unilateralis is responsible for an infection that causes the collapse of civilization.
In the 2022 comic-book series Poison Ivy written by G. Willow Wilson, the titular character makes use of a fictitious species belonging to this genus.
The Pokémon Paras and Parasect are based on insects parasitized by Ophiocordyceps.