A new species of Lactarius (subgenus Gerardii) from two relict Fagus grandifolia var. mexicana populations in Mexican montane cloud forests

Abstract

A new milkcap species, Lactarius fuscomarginatus, was found in the subtropical region of central Veracruz (eastern Mexico) associated with two relict populations of Fagus grandifolia var. mexicana. The species is characterized macroscopically by its dark pileus and stipe and by its distant and whitish lamellae with blackish to blackish brown edges. A molecular phylogenetic analyses based on ITS and LSU nucDNA sequences confirms the delimitation of this new taxon and places L. fuscomarginatus in subgenus Gerardii. A detailed morphological comparison is given with similar species.

• Ectomycorrhizal fungi
• Neotropical fungi
• Russulaceae
• Russulales
• taxonomy

Acknowledgments

We thank curators of the herbaria at K, MICH, NYS and TENN for loans of specimens. We appreciate the collaboration in the monitoring of Lactarius in the field and assistance in the laboratory by Biols. Pavel del Moral and David Ramos. Profesor Giovani Consiglio kindly prepared the Latin diagnosis and we appreciate also the collaboration of Giampaolo Simonini, both from Associazione Micologica Bresadola. We are also grateful for valuable comments made by two anonymous reviewers.