There are mushrooms that parasitize algae and aquatic organisms –vertebrates or invertebrates– and others that hunt them. Hundreds of predatory species are known. For example, the fungus Zoophagus tentaculum , which feeds on rotifers, microscopic beings that live in water.
The edible Pleurotus ostreatus , also known as the oyster mushroom, immobilizes and kills small nematode worms using toxins , then grows their filaments or hyphae and feeds on them. Several species of the genus Arthrobotrys also hunt them, but in their case they produce spore sacks or conidiophores wrapped in contractile rings that they use as a trap. These mushrooms of the genus Pleurotus are among the most prized edible mushrooms collected from nature by human mycophagi. These grow on the trunks of dying and dead trees and break the wood. Wood contains a lot of cellulose and lignin, but little nitrogen, which is why these crafty fungi exude chemical decoys to attract their microscopic nematode prey.
Manufacturing these elements is a great expenditure of energy , so they do it only when they are really hungry and know that their prey is close. Since they do not have sensory organs, they locate food through chemical signals. When worms crawl into fungal hyphae (threadlike filaments that make up most of the fungus’ mass), the fungus releases toxins from the tips of tiny, matchstick-shaped glands that paralyze the worms. The fungus then sends digestive hyphae out of the victim’s mouth. They penetrate the entire body and slowly digest the helpless worm from the inside while it is still alive.
The fight for survival has led to the evolution of very creative strategies to obtain food, such as the case of fungi that adopt this carnivorous lifestyle. While fungi generally feed on decaying organic matter, sometimes, as we see, it is not enough.
Carnivorous fungi are believed to have evolved around 419 million years ago, around 130-180 million years after the appearance of nematodes on this planet. Since then, carnivorous mushrooms have devised various ways to trap their prey.
Although this type of fungus has existed throughout human history, it was not until the 1890s that botanist and mycologist Friedrich Wilhelm Zopf recorded the first observation of carnivorous mushrooms in action (that we know of, at least). He saw the fungus Arthrobotrys oligospora capture live nematodes and began cultivating the fungi with eels in a chamber. The fungi took just two hours to capture and kill the eel worm.
Thus, in nutrient-poor habitats, instead of absorbing nutrients from the soil, these fungi and carnivorous plants have developed various forms of decoys and weapons, some of which rival the most vicious and brutal devices seen in any medieval torture chamber. , to lure and kill its hapless victims.
Reference: Science
