Two Lactarius species (subgenus Plinthogalus) in ectomycorrhizal association with tropical Quercus trees in eastern Mexico

ABSTRACT

Two species of Lactarius are documented from fragments of tropical lowland oak forest in central Veracruz. Lactarius trichodermoides, described here as new, was found in association with Quercus sapotifolia and Lactarius subplinthogalus with Quercus glaucescens. Both Lactarius species were identified morphologically and supported by phylogenetic analyses of nuc rDNA internal transcribed spacers (ITS1-5.8S-ITS2) and D1–D2 domains of nuc 28S rDNA sequences. Confirmation of mycobionts in ectomycorrhizal (ECM) associations was verified by molecular identification of ECM root tips. Detailed macroscopic and microscopic descriptions and photographs and illustrations of basidiomes and ectomycorrhizas are presented. The new binomial Lactarius chiangmaiensis is proposed for L. subplinthogalus var. chiangmaiensis.

KEYWORDS:

• Ectomycorrhizal ecology
• oak forest
• Russulales
• taxonomy
• 2 new taxa

ACKNOWLEDGMENTS

Assistance in the field and laboratory was provided by D. Ramos (Instituto de Ecología, A.C.) and J. C. Corona. Susana Valencia (Facultad de Ciencias, UNAM) kindly identified the Quercus species treated here. Drs. A. Ramos, E. Garay, and B. Pérez (INECOL) provided assistance with molecular procedures. We appreciate the comments and edits from two anonymous reviewers and the associate and executive editors.

Additional information

Funding

This research was supported by CONACYT (CB 252431) and a scholarship grant (261413) to MH. We also acknowledge support given by CONACYT 225382 to the Laboratorio de Presecuenciación, Red Biodiversidad y Sistemática, INECOL.