Originally described from Oaxaca, Mexico (as Porphyrellus alveolatus), the type specimen was preserved in formol, and lodged in the cryptogamic collections in the National Museum of Natural History in Paris, France. This specimen can no longer be found.

The Société Mycologique de France has kindly given permission to use the color plate and line drawing figures that were part of the protologue published in the Bull. Soc. Mycol. France 80: 88-101. 1964. I am grateful to B. Buyck for arranging this permission.

Based on the illustrations and the protologue, it appears very convincingly to be a later synonym of H. betula.