Catathelasma
Catathelasma is a genus of fungi in the family Biannulariaceae. Basidiocarps are agaricoid, with a conspicuous veil, adnate to decurrent lamellae, and amyloid basidiospores. The genus is separated on DNA characteristics as well as morphology. Species are known from North America, Europe, and Asia and are ectomycorrhizal, forming an association with the living roots of trees.
Taxonomy
The genus Catathelasma was originally described in 1910 by American botanist and mycologist Ruth Ellen Harrison Lovejoy with C. evanescens as the type species.in 1922 the Austrian botanist Günther [Beck von Mannagetta und Lerchenau] referred the European species Armillaria imperialis to his new genus Biannularia. For a time Catathelasma and Biannularia were regarded as separate genera, as for instance in a 1936 paper by Rolf Singer. Later Singer united the genera using Lovejoy's earlier name. Recent DNA research confirms this synonymy.
Etymology
Lovejoy's original description states that:According to Genaust's etymological dictionary of botanical names, "Catathelasma" comes from Ancient Greek words "kata" and "thelasma". He says that the reason for this construction is unclear, but suggests that the author is comparing the shape made by the gills running down the stem with a teat stretched out during suckling. "Decurrent" means "running down the stem" and another possible connection with Lovejoy's description is that "katatheo" means "I run down". However it is difficult to see how that could logically give rise to the noun "Catathelasma".