A research team has identified two mushroom species previously unrecorded in Japan, revealing overlooked fungal diversity in ordinary lawns. Combining microscopic observations with DNA analysis, the researchers confirmed the presence of Agrocybe broadwayi and Xuaniella urbica in warm-temperate grasslands. Both discoveries extend the species' known distributions eastward and show that familiar parks and recreational spaces still hold surprises for biodiversity research. The findings provide reference material for identifying lawn mushrooms and establish a foundation for investigating how fungi inhabit, and potentially move between, landscapes maintained by people.
Lawns in parks, sports grounds, and other managed spaces frequently produce mushrooms, particularly during Japan's rainy season and autumn. Some attract public attention, while others form fairy rings that concern turfgrass managers. Yet these accessible habitats have received far less systematic attention from mycologists than forests. Existing Japanese reports are largely fragmentary, leaving the composition and geographic distribution of lawn fungi poorly understood. Recent discoveries of previously undescribed fungi in grasslands suggest that this knowledge gap is substantial. More detailed surveys are therefore needed to establish which species occupy these everyday environments.
A study (DOI: 10.48130/panfungi-0026-0005 ) published in Panfungi on 28 August 2026 by Kaito Oguchi & Kentaro Hosaka, University of Tsukuba, documents two mushroom species in Japan for the first time, revealing overlooked fungal diversity in managed lawns and expanding knowledge of their geographic distributions.
The researchers surveyed warm-temperate lawns during 2024–2025, photographing mushrooms and recording their habitats before examining fresh specimens in the laboratory. They dried the collections, measured spores and other microscopic structures, and tested tissue reactions using standard chemical reagents. DNA extracted from dried material was used to sequence ribosomal markers: the internal transcribed spacer region for both species and the large subunit region for additional analysis of X. urbica. These sequences were compared with reference records, including material linked to the original specimens used to describe each species. Evolutionary trees then tested the proposed identifications. Three Japanese collections of A. broadwayi grouped strongly with its original specimen from Grenada and other reference collections. Their visible and microscopic features also supported the identification. The mushrooms occurred in Ibaraki and Mie prefectures, extending the species' documented range to its easternmost and northernmost known occurrence. One specimen contained unusual finger-like microscopic elements with elongated appendages, a feature not previously reported for this species. Sequences labeled Agrocybe retigera fell within the same group, reinforcing earlier suggestions that the two names may represent one species, although examination of the original A. retigera specimen remains necessary. Five Japanese collections of X. urbica, gathered in Chiba, Ibaraki, and Kanagawa prefectures, clustered strongly with Chinese specimens, including the original reference specimen. These slender, white-to-yellow mushrooms broadly matched the Chinese description, although their spores were somewhat larger. The records extend the species' confirmed distribution from Guangdong Province to approximately 36° north in Japan. Both species grew mainly in lawns dominated by Zoysia grasses, often in short, dense turf exposed to frequent trampling. Their occurrence suggests an association with disturbed grasslands maintained through human activity. The authors also raise the possibility that turfgrass-related activities have helped disperse A. broadwayi, but the study does not establish when or how it reached Japan.
Together, the findings show that managed lawns deserve closer attention as fungal habitats. They also illustrate why combining DNA evidence with detailed microscopy matters when distinguishing similar mushrooms and interpreting geographic records. Broader surveys could reveal whether these fungi are widespread but overlooked across East Asia. For X. urbica, reports of illness following consumption in China add a practical reason to improve identification and awareness of mushrooms growing in public spaces.
