an entangled mass of hyphae called the hapteron. The spores of C. helenae have a spherical or ovoid shape, with dimensions of 12–14 µm long by 15–19 µm wide. They tend to be slightly narrower at one end, and commonly have a spore wall thickness of 1.5 µm.Cyathus helenae is distinguished from the more common C. striatus by its faint inner-surface plication (C. striatus has a more pronounced plication), the nodular arrangement of the hairs on the outer surface, and microscopically by the spore shape – ellipsoid in C. striatus, ovoid or spheroidal in C. helenae. Habitat and distribution The species was initially described by mycologist Harold J. Brodie in 1965, who collected it from Rocky Mountain Park in Alberta, Canada at an altitude of . It was found growing among the small flat stones of the scree, often attached to rotted or dried remains of alpine plants. Brodie derived the species name as a tribute to his late wife Helen. This species is known to live in alpine and boreal habitats, as well as dry areas in Idaho. In 1988 C. helenae was first reported in Mexico; in 2005 it was reported growing in tropical forest in the Calakmul Biosphere Reserve (Calakmul, Mexico), and in Costa Rica. In 2014, it was recorded in Brazil, the first report of this species from South America. Life cycle The life cycle of Cyathus helenae contains both haploid and diploid stages, typical of taxa in the basidiomycetes that can reproduce both asexually (via vegetative spores), or sexually (with meiosis). Basidiospores produced in the peridioles each contain a single haploid nucleus. After dispersal, the spores germinate and grow into homokaryotic hyphae, with a single nucleus in each compartment. When two homokaryotic hyphae of different mating compatibility groups fuse with one another, they form a dikaryotic mycelia in a process called plasmogamy. After a period of time and under the appropriate environmental conditions, fruit bodies may be formed from the dikaryotic mycelia. These fruit bodies produce peridioles containing the basidia upon which new basidiospores are made. Young basidia contain a pair of haploid sexually compatible nuclei which fuse, and the resulting diploid fusion nucleus undergoes meiosis to produce haploid basidiospores. Spore dispersal When a drop of falling water hits the interior of the cup with the appropriate angle and velocity, the peridioles are ejected into the air by the force of the drop. The force