Purpureocillium atlanticum: a fungus from a Brazilian spider burrow

A small structure above a burrow entrance

Purpureocillium atlanticum was described from a fungus associated with a trapdoor spider. White mycelium covered the host, while a spore-bearing structure that developed purple colouring grew towards the burrow opening. What could be seen above the ground was therefore only part of a system involving the fungus, the animal and its shelter.

The IMA Fungus description appeared in 2025. The name is attributed to J.P.M. Araújo, K. Martins-Cunha, A. Antonelli and E.R. Drechsler-Santos. The material was compared with the broadly interpreted P. atypicola complex, which includes fungi found on spiders in different regions of the world.

A preserved specimen anchors the name

Holotype FLOR 73173 was collected on 22 November 2022 at Alto da Figueira reserve near Nova Friburgo, Rio de Janeiro state. It is held in the herbarium of the Universidade Federal de Santa Catarina. The Species Fungorum record links the name to its publication and specimen. Collection therefore preceded formal description by several years.

The authors compared the spore-bearing structures, conidium-producing cells and conidia themselves, alongside molecular data and host ecology. The epithet atlanticum refers to the Atlantic Forest. It does not describe a connection with seawater.

Genetic work can begin during fieldwork

The study used portable nanopore sequencing to accelerate the production of genetic data without moving every stage to a distant laboratory. The researchers also examined sequences associated with the sample. Such reads require interpretation: detecting another organism's DNA does not by itself establish a lasting symbiosis or demonstrate that organism's role in infection.

Portable sequencing does not replace the foundations of taxonomy. A preserved specimen, comparisons with described relatives and an explicit diagnosis are still needed. Obtaining sequence data more quickly does not mean that every detected lineage automatically receives a new species name.

Where the “zombie fungus” story stops

The collection documents parasitism of a spider, but it is not an experiment demonstrating manipulation of the spider's behaviour. Results from fungi associated with ants should not be transferred to every fungus infecting an arthropod. Nor does this paper assess a risk to people.

The authors identify major gaps in distributional knowledge and propose Data Deficient. Here that is presented as their assessment within the paper, not as confirmation of a separate published IUCN Red List entry. One documented locality justifies further surveys and attention to habitat context. By itself, however, it establishes neither the complete geographical range nor a quantified probability of extinction.