Agaricus subgenus Pseudochitonia in Malakand, Pakistan: An updated phylogeny and description of three new species

ABSTRACT

Agaricus is a genus with more than 500 species. Most of the new species reported since 2000 are tropical or subtropical. The study area, the Malakand region, located in the north of Pakistan, has a subtropical climate. In this study, nine species, including three new species, of Agaricus subgenus Pseudochitonia, are reported from this region. Description of the new species are based on morphological characteristics and phylogenetic analyses using three DNA regions: nuc ribosomal DNA internal transcribed spacers (ITS), fragments of the large subunit of nuc ribosomal DNA (28S), and the translation elongation factor 1-alpha gene (TEF1). One new species, Agaricus lanosus, with wooly squamules on its cap, forms a lineage within Agaricus sect. Bivelares and cannot be classified with certainty in one of the two subsections (Cupressorum and Hortenses) of this section. Agaricus rhizoideus with rhizoid-like structure at the base of the stipe forms a basal clade in Agaricus sect. Hondenses. Specimens of the third new species, Agaricus malakandensis, form a species-level clade within Agaricus sect. Catenulati and exhibits the morphological characteristics of this section. Due to their similar ITS sequences, two previously unnamed specimens from Thailand (A. sp. LD2012162 and CA799) are considered conspecific with A. malakandensis.

KEYWORDS:

• Agaricaceae
• Malakand
• morphology
• taxonomy
• 3 new taxa

ACKNOWLEDGMENTS

We thank Mounia Benazza (MycSA lab, France) for measuring the spores of collection CA799. We also thank Linda J. Chen (Universidad Veracruzana, Mexico) for sharing the photos and sequence chromatograms of her collection of A. malakandensis (LD2012162). We thank the two anonymous reviewers for their reviews and comments in refining this study. We would like to dedicate this work to one of the great mycologists and Agaricus expert, Professor Dr. Philippe Callac (late), who has significantly contributed to this article before passing away on 25 August 2023.

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/10.1080/00275514.2024.2334473

Additional information

Funding

This work was supported by the Higher Education Commission of Pakistan.