New research has shown that the world’s deadliest mushroom, the “death cap,” has found a new way to reproduce.
The lethal mushroom has been spreading across Canada and the United States. Formally called Amanita phalloides, it is extremely toxic to humans. The species originated in Europe but has quickly been finding a new home all across North America.
A. phalloides is one of the most poisonous of all known mushrooms. It is estimated that as little as half a mushroom contains enough toxin to kill an adult human. It has been involved in the majority of human deaths from mushroom poisoning,
The mushroom is thought to be responsible for the deaths of Roman Emperor Claudius in AD 54 and Holy Roman Emperor Charles VI in 1740. The principal toxic constituent is α-Amanitin, which causes liver and kidney failure.
CTV News Canada is reporting that according to a study published by Cold Spring Harbor Laboratory in bioRxiv, a preprint publication, death caps are reproducing alone.

Maxim Shashkov, CC SA 4.0.
The study led by researchers at the University of Wisconsin-Madison on A. phalloides in the US has found the mushroom can produce spores using the chromosomes of a single individual, according to Science Alert.
The discovery is based on the genomes of 86 mushrooms, collected in California since 1993 and parts of Europe since 1978. Among some of the mushroom samples from California, it was found that death caps appear to have been able to reproduce both sexually and asexually for at least 17 years, and possibly as long as 30 years.
“The diverse reproductive strategies of invasive death caps are likely facilitating its rapid spread, revealing a profound similarity between plant, animal, and fungal invasions,” the researchers write in their new paper.
The death cap mushroom – over recent decades – has been incredibly successful at invading new habitats in other parts of Europe, as well as North America and Australia. Asexual reproduction could be a big reason why.
There are about 100 sightings of death caps in British Columbia on Vancouver Island and across the lower mainland, the B.C. Centre for Disease Control (CDC) website states. The mushrooms look similar to the Asian straw mushroom and other varieties and grow within urban areas
