Lepiota

Lepiota is a genus of gilled mushrooms in the family Agaricaceae. All Lepiota species are ground-dwelling saprotrophs with a preference for rich, calcareous soils. Basidiocarps (fruit bodies) are agaricoid with whitish spores, typically with scaly caps and a ring on the stipe. Around 400 species of Lepiota are currently recognized worldwide. Many species are poisonous, some lethally so. Agaricus section Lepiota was originally published in 1797 by South African-born mycologist Christian Hendrik Persoon. It was subsequently raised to the rank of genus by Samuel Frederick Gray. As originally conceived, the genus was a mix of agarics with rings on their stems, including species now placed in Armillaria, Cortinarius, and Pholiota. In 1822, however, the influential Swedish mycologist Elias Magnus Fries restricted Lepiota to white-spored, ringed agarics. Based on macro- and micromorphology, later authors gradually refined the generic concept of Lepiota. Some unrelated genera, such as Cystoderma (Fayod 1889) and Limacella (Earle 1909), were removed from the genus whilst several related genera, including Leucocoprinus (Patouillard 1888), Macrolepiota and Leucoagaricus (Singer 1948), Cystolepiota (Singer 1952), and Echinoderma (Bon 1991) were separated off. These segregated genera, together with Lepiota itself, are still often grouped together as Lepiota s.l. (sensu lato = "in the wide sense") or as the "lepiotoid" fungi. The secotioid species Amogaster viridiglebus, described in 1996 and initially placed in the order Boletales, was later determined to be a member of Lepiota, and officially transferred to the genus in 2013. Following some discussion over the type species, Lepiota has now been conserved under the International Code of Nomenclature for algae, fungi, and plants, typified by Agaricus colubrinus Pers. (= Lepiota clypeolaria). Recent molecular research, based on cladistic analysis of DNA sequences, suggests that the morphological concept of Lepiota s.s. (sensu stricto = in the strict or narrow sense) is soundly based.