The discovery of a new poisonous mushroom in the Iberian Peninsula
Gabriel Moreno, a professor and mushroom expert from the University of Alcalá, joined colleagues from French institutions and researchers at the University of Seville. Together they identified a deadly mushroom that belongs to the Amanita family, a species associated with severe poisoning. This new find is related to Amanita phalloides, commonly called the widow’s amanita by locals due to its dangerous nature.
The breakthrough came from studying the timing of poisonings. Amanita phalloides is widely recognized as one of the most lethal mushrooms for humans and typically fruits in autumn in holm oak, cork oak, oak, and pine forests. Yet poisonings occur annually, and without prompt hospital treatment the outcomes can be fatal. Even with care, liver damage or transplant may be required. For years, scientists have also faced spring poisonings from white fungi that puzzled experts.
A similar venomous species known as the spring amanita prompted researchers to conduct a decade of collaborative work across multiple institutes. The team sought to determine whether the spring gifts of mushrooms included a second toxin producer and how it related to known species.
According to the lead researcher, a hitherto unidentified mushroom was described. It closely resembles the edible mushroom often prized in western Andalusia and is widely confused with it. The discovery helped clarify the cases of poisoning reported by local doctors, particularly in Huelva and southern Extremadura, as well as across Portugal in Ribatejo and Alentejo. This new toadstool is highly similar to the well known fly agaric but proves to be a distinct species that emerges in spring. The new mushroom and its seasonal cousin share a Mediterranean climate and habit of growing in holm oak and cork oak groves on the Iberian Peninsula.
Further analysis showed that the two morphologically similar mushrooms coexist in spring. One is the familiar fly agaric and the other is the newly identified widow’s amanita. The discovery highlights that both thrive in the same landscapes, yet they are separate species with distinct toxic profiles. The team’s work indicates that the new species possesses active compounds comparable to alpha and beta amanitins, the same toxins found in autumn Amanita phalloides. These substances attack the liver and can trigger late onset symptoms six to eight hours after ingestion, including severe vomiting followed by abdominal pain and rapid liver failure if untreated.
The only reliable way to distinguish poisonous from edible mushrooms remains expert guidance. Attending mycological society conferences and consulting specialists can prevent misidentification, as many edible species have toxic relatives that look similar. Practical advice from field experts emphasizes examining the mushroom carefully, noting features like the volva, and avoiding any consumption when the species is uncertain.
In this field, ongoing research and collaboration help clarify risks and improve public awareness. The study underscores the importance of cautious foraging and professional verification before consumption. The findings contribute to a broader understanding of mushroom toxicity and the ways in which closely related species can determine health outcomes for foragers and communities alike. The work is documented with scientific evidence and is attributed to the involved researchers and institutions. Citation: biology article with DOI 10.3390/biology11050770.
Environmental authorities and research teams continue to study springtime Amanita manifestations to protect foragers and inform medical guidelines. The evolving knowledge in this area supports safer practices and more accurate public health messaging across the Iberian Peninsula and beyond.