Two intimately co-occurring species of Mycena section Sacchariferae in south-west Australia

Two diminutive, lignicolous species of Mycena section Sacchariferae are described from Western Australia: Mycena judithiana sp. nov. of stirps Amparoina, and Mycena tenerrima of stirps Adscendens. M. tenerrima had been unrecorded in Western Australia and unconfirmed in Australia. Six morphological stages of the diphasic mode of development of M. judithiana were characterized by observing a succession of basidiomes produced on incubated fragments of wood from which the fungi were originally collected. A wood fragment from which M. tenerrima was originally collected yielded basidiomes of that species for the first 25 days of incubation and then also began to produce basidiomes of M. judithiana. This indicates how closely the two species can co-occur in south west Australia and perhaps elsewhere.