Dark taxa are species known only from eDNA sequences. In the natural sciences, when a species is described, the name consists of two Latin words to describe the species and the genus. This allows for categorization of plants, animals, and fungi. Mycorrhizal fungi are collected (soil and root samples) in nature. Fungal eDNA (environmental DNA) is extracted from the samples and sequenced. The sequences are then put through a bioinformatic pipeline to match the sequence to a described species. Dark taxa are species which are only known from sequences.  

Approximately 155,000 of the 2–3 million fungal species on the planet have been formally described and named, with dark taxa representing the vast majority of species within the Fungal Kingdom.

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