Purple Pinwheel and more: The Marasmius haematocephalus complex (Marasmiaceae) in Australia.

Marasmius haematocephalus forms a distinctive pan-tropical species complex. While it has been confirmed that M. haematocephalus s. s. occurs only in the neotropics, morphologically similar taxa across the world continue to be attributed to this species. Phylogenies utilising nrITS, nrLSU and TEF1, were constructed to identify relationships within the complex, and morphological data used to document and explore the taxa endemic to Australia and those which co-occur in Asia, Madagascar and the USA. Seven new species found in Australia are described and illustrated - M. campaniformis sp. nov., M. pervagatus sp. nov., M. porphyrocephalus sp. nov., M. purpureospadiceus sp. nov., M. vinaceus sp. nov., M. wianwian sp. nov. and M. wunga sp. nov. A key to Australian species of the M. haematocephalus complex is provided. Historic records and observational data (iNaturalist and Atlas of Living Australia) were used to indicate potential distributions of all species within the complex that occur in Australia and explore biogeographic relationships more broadly. Citation: Guard FE, Dearnaley J, Lebel T (2025). Purple Pinwheel and more: The Marasmius haematocephalus complex (Marasmiaceae) in Australia. Fungal Systematics and Evolution 16: 283-305. doi: 10.3114/fuse.2025.16.16.