Ten new species of <i>Leucoagaricus</i> and <i>Leucocoprinus</i> from Beijing: Revealing rich diversity in temperate regions

<i>Leucoagaricus</i> and <i>Leucocoprinus</i> (Agaricaceae) exhibit global distribution, with notable abundance and diversity in tropical and subtropical regions and play as decomposers in the ecosystem. However, a recent survey of macrofungi in the urban area of Beijing resulted in the discovery of a rich diversity of these fungi. In this study, 88 <i>Leucoagaricus</i> and <i>Leucocoprinus</i> specimens have been collected from Beijing. The following morphological examination and phylogenetic analysis based on ITS and nrLSU sequence data, complemented by a four-gene dataset (ITS, nrLSU, <i>rpb2</i>, and <i>tef1-α</i>) identified them into 22 species, including eight new species in <i>Leucoagaricus</i>: <i>La. bulbosus</i>, <i>La. centrobrunneolus</i>, <i>La. cinereibisporus</i>, <i>La. luteocanus</i>, <i>La. subcandidus</i>, <i>La. subnivalis</i>, <i>La. testaceumbonatus</i>, and <i>La. xantholepis</i>, and two new species of <i>Leucocoprinus</i>: <i>Lc. beijingensis</i> and <i>Lc. digitatocystis</i>. Detailed descriptions of all proposed new species are provided. Additionally, three new combinations in <i>Leucocoprinus</i> were proposed, and four <i>Leucocoprinus</i> names were reinstated. This research expands the understanding of <i>Leucoagaricus</i> and <i>Leucocoprinus</i> species diversity, especially the distribution in temperate regions. The rich species diversity of those mushrooms also indicated urban habitats specially urban green land, despite being heavily influenced by human activity, may serve as unexpected hotspots of biodiversity because they can provide a favourable ecological environment.