Leucocoprinus is a genus of fungi in the family Agaricaceae. Its best-known member is the distinctive yellow mushroom Leucocoprinus birnbaumii, which is found in plant pots and greenhouses worldwide. The type species is Leucocoprinus cepistipes. The genus has a widespread distribution and contains over 80 recognised species, however many of these species are very scarcely recorded and little known with only a small number of Leucocoprinus species which are commonly observed. The majority of the species in this genus are exclusive to tropical environments however numerous species have become a common sight in plant pots and greenhouses resulting in them becoming well known worldwide. It is likely that some of the observations for these common species are misidentified with observations for L. birnbaumii in particular often being conflated with other species simply because it is better known or more frequently suggested by image recognition algorithms. Taxonomy The genus was created in 1888 by the French mycologist Narcisse Théophile Patouillard. Due to the superficially similar features which many Leucocoprinus, Leucoagaricus and Lepiota species have these genera and the species within them have been subject to a great deal of reclassification over the years. One example of this is Leucoagaricus leucothites which has numerous synonyms formerly belonging to all three genera. These genera along with Cystolepiota, Chlorophyllum and Macrolepiota are often referred to as Lepiotoid mushrooms. Typical macroscopic characteristics include white spore prints, the presence of a stem ring formed from the partial veil and gills which are free from the stem. There are always exceptions to these details however. Flaky or woolly scales on the cap or stem of these mushrooms and a distinctly coloured central disc are common features amongst many species but are likewise observed in many other genera. Reliable identification of Lepiotoid mushrooms at the species level can be notoriously difficult. Many species can only reliably be distinguished by microscopic details and chemical reagent tests. Species The most commonly known and recorded species are ones which occur in plant pots, these include: Leucocoprinus birnbaumii Leucocoprinus brebissonii Leucocoprinus cepistipes Leucocoprinus cretaceus Leucocoprinus flavescens Leucocoprinus fragilissimus Leucocoprinus heinemannii Leucocoprinus ianthinus Leucocoprinus straminellus Leucocoprinus tricolor These species have been documented growing in plant pots and greenhouses and so may have a worldwide distribution in captivity with introduction into the wild being possible where temperatures are suitable for these tropical species. Many of the most known species were originally described from greenhouses