Malaysian scientists discover hyperparasitic fungus in Borneo that attacks zombie fungi

A fungus that lives off another fungus has been named from the forests of Danum Valley in southern Sabah, adding a new twist to the already strange cordyceps world mushroom hunters know well. The species, Pleurocordyceps cornusynnemata, was collected on multiple field trips by the University of Malaysia Sabah’s Institute for Tropical Biology and Conservation and published in Phytotaxa in April 2026.

The new find does not attack an insect directly. Instead, it targets ants already infected by Ophiocordyceps, the so-called zombie fungus that takes over insect bodies. Jaya Seelan Sathiya Seelan, deputy director of the institute, described it as a specialized hyperparasite, meaning it parasitizes the primary pathogen itself. In practical terms, it feeds directly on the Ophiocordyceps tissue inside the host rather than manipulating the ant’s nervous system.

For mycologists, that places the species in a rare and layered corner of the fungal kingdom. The paper, titled Taxonomy and phylogeny of Pleurocordyceps (Polycephalomycetaceae, Hypocreales) associated with ants and cicadas from Malaysia, including a new species and new records, used morpho-molecular analyses to place the fungus within Pleurocordyceps. Researchers also identified it as the first known member of its genus with a distinctly horn-shaped structure, a detail that stands out even among the weird architecture cordyceps collectors and fungal nerds love to chase through tropical forests.

The same field trips also turned up a new spider-killing fungus, underscoring how much of Borneo’s insect-associated fungal life still sits outside the books. That is part of what makes the Danum Valley work matter to foragers and hobby mycologists alike: the wild mushroom landscape is not just about caps, stems, and edibility, but about a hidden web of parasites, hosts, and counter-parasites that shape the forest floor and canopy out of sight.

Seelan said the newly documented fungi may have potential in next-generation antimicrobial drug development and in biocontrol against agricultural pests. Even when a species will never show up in a basket, a find like Pleurocordyceps cornusynnemata expands the sense of how much is still undiscovered in tropical fungi, and how many more layers are working beneath the surface of a single dead ant.