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Parasect, a Pokémon controlled by the tochukaso on its back
Tochukaso (Japanese: 冬虫夏草 tōchūkasō) is a rare species of parasitic mushroom that grows on Paras and Parasect.
Paras removing its tochukaso
Tochukaso spores are attached to Paras Eggs, causing hatched Paras to be doused in them when they hatch. As the Paras grows, so does the tochukaso. The tochukaso orders its host to suck nutrients from tree roots and trunks, then absorbs most of the nutrition itself. When the Paras evolves into Parasect, the tochukaso takes complete control of the host and does all the thinking.
Tochukaso prefer damp, dark places, so Parasect are typically found in those locations due to it being controlled entirely by the fungus. The fungus scatters its toxic spores from the mushroom cap, and uses the host to help distribute these spores.
In Clefairy and the Moon Stone, the lighting Team Rocket hung up in Mt. Moon confused the Paras, causing them to remove their tochukaso and plant them in the ground, as the fungus dislikes bright light.
Tochukaso spores can be used to make a herbal medicine which can be used to extend life; this medicine is commonly made in China.
In The Problem with Paras, Cassandra is tried to evolve her Paras into Parasect in order to harvest its spores to produce a miracle potion; a miracle potion restores a Pokémon attack power, defenses, concentration and determination, and make it smarter. Eventually her Paras evolves, and her and her grandmother set up a business to produce and sell miracle potions.
Tochukaso is a fungus in the real world that is an endoparasitoid that replaces the host tissue and can affect the behavior of its insect host. In Parasect, the tochukaso has caused neoteny. The fungus is often used in traditional Chinese medicine, specifically as an aphrodisiac and for treatment for ailments such as fatigue and cancer.
- As Paras and Parasect are often found in the wild holding them, and due to their visual similarity, TinyMushrooms and Big Mushrooms may be tochukaso.