Morchella tomentosa: a unique belowground structure and a new clade of morels

Mechanisms involved in post-fire morel fructification remain unclear. A new undescribed belowground vegetative structure of Morchella tomentosa in a burned boreal forest was investigated north of Fairbanks, Alaska. The name radiscisclerotium is proposed to define this peculiar and elaborate belowground vegetative structure of M. tomentosa. Bayesian and maximum parsimony analyses based on ITS rRNA regions and nLSU gene strongly supported a new clade composed of M. tomentosa within the genus Morchella.