Tuber caryophilum, a new truffle species growing in Carya illinoinensis orchards

Abstract

Tuber is a genus of ectomycorrhizal fungi with an important diversity of species associated with hosts in Juglandaceae. Tuber caryophilum is proposed as a new species based on ecological, morphological and phylogenetic characters of 2 ribosomal markers (ITS and LSU). This species is characterized by forming ectomycorrhizae on the roots of Carya illinoinensis (nogal pecanero) in the Comarca Lagunera of Coahuila and Chihuahua, Mexico and by exhibiting 18-48 × 10-27 μm echinulate ascospores. Tuber caryophilum belongs to the Rufum clade and is the sister species of Tuber theleascum, a species reported in northern Mexico associated with Quercus canbyi and Q. polymorpha. These 2 truffles belong to a clade from the southern USA and northern Mexico with taxa associated to Quercus and Carya, such as Tuber lyonii.