Downfall of an empire: Unmasking the hidden diversity and distribution of the Amanita rubescens species complex

ABSTRACT

Amanita is one of the most salient mushroom genera due to its cultural, economic, and medical importance. Recently, many new Amanita species have been described worldwide, increasing the genus richness. However, several clades have cryptic diversity, and many species complexes have not yet been resolved. This is the case of the rubescent species in the Validae section, which have been widely cited under the name Amanita rubescens s.l. We used a four-locus matrix (nuc rDNA internal transcribed spacer [ITS] and 28S regions and genes for RNA polymerase II subunit 2 [rpb2], translation elongation factor 1-α [tef1-α], and β-tubulin [tub2]) to solve the phylogenetic relationships within the Amanita section Validae. To analyze the diversity and distribution patterns of species, we used an extensive ITS sequence sampling including environmental DNA databases. The phylogenetic analyses demonstrated that the Validae section is divided into three monophyletic and highly supported major clades: Mappae, Validae, and Rubescentes. At least 11 species-level clades within the Rubescentes clade were highly supported: A. cruentilemurum nom. prov. A. brunneolocularis, A. rubescens s.s. (European clade), A. rubescens s.s. (Asiatic clade), A. orsonii s.s. A. ‘orsonii,’ A. aureosubucula nom. prov., A. novinupta, A. flavorubens, and two undescribed North American species. We proved that A. rubescens s.s. has two segregated populations (European and Asiatic) and it is not naturally distributed in America. Furthermore, we found that America has more cryptic species within the Rubescentes clade than Eurasia.

KEYWORDS:

• Amanita
• blusher
• distribution
• diversity
• phylogeny
• rubescent
• species complex

ACKNOWLEDGMENTS

C.A.Q.-C. is a PhD student in the Posgrado en Ciencias Biológicas (Universidad Nacional Autónoma de México). The present research is presented by C.A.Q.-C. as a requirement to obtain the PhD degree in biological sciences. We thank Dr. Alicia Mastretta Yanes and Dr. Luis David Alcaraz for their guide and brainstorming. We also thank CONABIO for its bioinformatic cluster.

DISCLOSURE STATEMENT

No potential conflict of interest was reported by the author(s).

SUPPLEMENTARY MATERIAL

Supplemental data for this article can be accessed online at https://doi.org/10.1080/00275514.2024.2355276

DATA AVAILABILITY STATEMENT

Unique haplotype data are deposited to NCBI Nucleotide Database (https://www.ncbi.nlm.nih.gov/nuccorehttps://www.ncbi.nlm.nih.gov/nuccore):

ITS: MZ014386–MZ014395, OR506120–OR506128, OR506145.

rpb2: OP584270–OP584280, OR529182–OR529191.

28S: OP594911–OP59492, OR506129–OR506137.

tef1-α: OR498098–OR498115.

β-Tubulin: OR498089–OR498096, OR529192–OR529193

Additional information

Funding

C.A.Q.-C. is supported by the Consejo Nacional de Humanidades, Ciencias y Tecnologías (CONAHCYT), Mexico [scholarship no. 696992]. This research was supported by the project UNAM-PAPIIT IN212521, funded to R.G.-O.