Nats truffle and truffle-like fungi 5: Tuber Iyonii (= T. Texense), with a key to the spiny-spored Tuber species groups

Abstract

As a result of examination of the type of Tuber Iyonii Butters and numerous collections of Tuber texense Heimsch, the latter is synonymized with the former. The species is redescribed to er compass its known phenotypic variation, and its range is extended from earlier reports in Texas, Georgia and Ohio to the presently known range of northeastern Mexico north to New Mexico, then east along the Gulf Coast to Florida and north to Minnesota, Québec, New York and Connecticut. The 3-layered wall of the asci of T. Iyonii is described, and a key is provided to the three Tuber spp. that have spores ornamented with spines connected by a low reticulum.