Characterization of New Tropicoporus Species (Basidiomycota, Hymenochaetales, Hymenochaetaceae) Discovered in Tamil Nadu, India

This study aimed to investigate the morphological characteristics and phylogenetic relationships of three new species of <i>Tropicoporus</i> from the southern parts of India. The analyses of the ITS and nLSU regions revealed the novelty of these species, which have been named <i>T. pannaensis</i>, <i>T. subindicus</i>, and <i>T. xerophyticus</i>. All three species possess pileate basidiomes, a monomitic hyphal system in the context, and the presence of cystidioles and setae. However, they differ significantly in their phylogenetic placements and other morpho-taxonomic features. <i>Tropicoporus pannaensis</i> is characterized by a meagrely ungulate basidiome, indistinct zones, and an obtuse margin. <i>Tropicoporus subindicus</i> has a triquetrous basidiome and a radially cracked, crusted pileal surface with an acute margin, while <i>T. xerophyticus</i> is distinguished by an imbricate, perennial basidiome with an abundantly warted pileal surface. A phylogenetic tree is provided to show the placement of the three new species, along with detailed descriptions and illustrations. Additionally, a key for the identification of the Asian species of <i>Tropicoporus</i> is presented.