The order Entorrhizales is a small group of fungi within the phylum Basidiomycota, primarily known for their root-infecting lifestyles. Members of this order form obligate symbiotic or parasitic relationships with the roots of certain plants, especially in the families Cyperaceae and Juncaceae. They produce teliospores, a type of thick-walled resting spore, which play a key role in their life cycle and reproduction. Entorrhizales fungi are generally microscopic and soil-dwelling, and although they do not form the large fruiting bodies seen in many other basidiomycetes, they are important for studying fungal evolution and plant-fungal interactions. Their biology is still relatively poorly understood due to their cryptic nature and specialized habitat.