Distinct basidiospore development in Tricholosporum laeteviolaceum

The genus Tricholosporum is characterised by cruciate spores. The formation of these basidiospores and their subsequent growth until release from the sterigmata, is described from a sequence of SEM photographs. The spores on a basidium form either a diad, a triad or a tetrad during their development. The outer cell wall layer of the basidiospore enlarges, resulting in the cruciate shape of the spores and the ultimate calyptrate appearance after release when desiccated. The spores are seceded sequentially.