Fungi with prominent hairlike rhizomorphs, aerial habit, sparse small sporophores, and usually saprotrophic biology are commonly known as ‘horsehair or spider fungi’. The earliest descriptions of them, from the mid-late 1800s, were published from Australian material under the names Marasmius crinis-equi and M. equicrinis . For the original ‘horsehair fungus’, we review this early historical material, briefly explore the change...