Comprehensive morphological and phylogenetic inferences of star-shaped fungus Astraeus (Diplocystidiaceae) from sal-dominant tropical and subtropical Pinus-Shorea forests in India: an integrative taxonomic analysis

Abstract

Classifying fungus based on morphological traits is an effective strategy to distinguish between puffballs, earthballs, earthstars, and other gasteroid fungi, as well as for identifying sub-groups of closely related taxon. However, to delimitate taxa it should be addressed with caution, since cryptic species have been described recently in different genera of gasteroid fungi. Astraeus is a star-shaped fungus that has piqued the interest of mycologists worldwide, including India. These endearing fungi have tremendous nutritional and therapeutic benefits, but their molecular and phylogenetic placement in India is uncertain. An integrative taxonomic approach was used to identify and resolve ambiguities within the genus. This study, the first to elucidate the distribution, taxonomy, and phylogeny of the genus Astraeus in the mixed subtropical Pinus-Shorea forest and tropical dry deciduous Shorea dominated forest in India, aims to shed light on these indispensable ectomycorrhizal fungi. The phylogenetic analysis assigned all thirteen ITS DNA barcoding Indian sequences of Astraeus to the Southeast Asian clade, reinforcing the genus Southeast Asian origin. Detailed species descriptions, line diagrams, SEM images of basidiospores, ITS nrDNA based phylogeny, and a dichotomous key are provided. Mycoobservations of the taxon from Pinus-Shorea subtropical and Shorea-dominated forests were additionally reviewed.