From MykoWeb:

“This false morel was historically placed in Helvella, and more recently in Gyromitra. Harmaja (1976), transferred it to Pseudorhizina citing a number of morphological and chemical differences, the most obvious being a ribbed cap with a tomentose undersurface, pinkish stipe, and smaller spores with oil drops that are variable in size and number. Recent DNA evidence supports Harmaja’s transfer. Pseudorhizina sphaerospora of Eastern North America is very similar, differing as the species suggests, by globose spores.”