A new corticioid Auriculariales (Basidiomycota) fungus on rattan, Alloexidiopsis rattanicola sp. nov., from National Park of Hainan Tropical Rainforest, China

Hainan Province, also known as National Park of Hainan Tropical Rainforest and one of the most biodiverse regions in China, has seen the discovery and description of many wood-decaying fungal species in recent years. During the sampling trip in July 2025, a potential new rattan-decaying fungal species was found in the Hainan province. Phylogenetic analyses showed that A. rattanicola is closer to A. yunnanensis, with both species forming a subclade at the base of the genus Alloexidiopsis. This species was confirmed to belong to Basidiomycota, Agaricomycetes, Auriculariales, Auriculariaceae, and Alloexidiopsis, and is described here as Alloexidiopsis rattanicola based on phylogenetic and morphological studies. Morphologically, Alloexidiopsis rattanicola is characterized by barrel-shaped basidia, capitate basidioles, and allantoid basidiospores, as well as growing on rattan plant. This study enriches the diversity of macrofungal species in Hainan province, providing new data on rattan-decaying fungi.