Shintaku, MichaelStallman, Jeffery Kirk2019-04-162019-04-162019-05http://hdl.handle.net/10790/4585The fungi are a hyperdiverse group of important organisms, many of which remain undescribed and unknown, particularly from tropical habitats. This project documenting the lepiotaceous fungi (Agaricaceae: Lepiotae, Leucocoprinae) of Hawaiʻi Island resulted in 148 collections from September 2016–January 2019. Based on these collections and prior records, 38 species of lepiotaceous fungi from Hawaiʻi Island are reported: two in Chlorophyllum, one in Cystolepiota, seven in Lepiota, 15 in Leucoagaricus, and 13 Leucocoprinus. Two new records of previously undocumented species from Hawaiʻi, Leucocoprinus straminellus and Leucoagaricus cf. americanus, are reported, along with 21 additional species that could not be assigned to a known taxon. Two potentially undescribed Lepiota spp. likely contain poisonous amatoxins. General descriptions and a dichotomous key are provided for all taxa with sufficient information, and a phylogenetic analysis of the genus Lepiota, including the two potentially-deadly species based on nrITS sequences, is presented.201 pagesenBiologyAgaricaceaeFungiHawaiʻiLepiotaTaxonomy