Tricholoma Pessundatum is a type of mushroom that belongs to the Genus Tricholoma family. It is commonly known as the "mustard tricholoma", owing to its yellowish-mustard coloration. Other synonyms for this mushroom include Agaricus Pessundatus, Tricholoma Terreum, and Agaricus Terreus. It is typically found in coniferous forests during the fall season. The mushroom's cap often grows up to 15 cm in diameter, while its stem can grow to up to 10 cm in length. Though it is consumed in some parts of the world, it can be toxic when not prepared correctly. Synonyms like "yellow tricholoma" and "mustard umbrella" are often used to avoid confusion and highlight its distinctive coloration.