Exophiala zingiberis sp. nov., a novel cellulase-producing black yeast-like fungi isolated from ginger in India

The genus Exophiala , known for its melanized, yeast-like appearance, includes a diverse group of fungi with significant implications across various fields. An isolate representing a novel species was identified within this genus from a ginger tuber from India, based on morphological characteristics and molecular phylogenetic analysis. Phylogenetic analysis of the D1/D2 domain of the 26S LSU rRNA gene, SSU rRNA gene and the internal transcribed spacer (ITS) region confirmed this strain as a new species. It was named Exophiala zingiberis sp. nov. (MycoBank no. MB 855415), with MCC 9960 T designated as the holotype and PYCC 9834 as the isotype. Exophiala zingiberis was positioned as a sister species to a clade that includes Exophiala castellanii , Exophiala mali and three additional species. Phylogenetic analysis indicates that while E. zingiberis shares a common ancestor with these species, it is genetically distinct, underscoring its novel status. The type strain of this novel species differs from Exophiala yuxiensis YMF1.07354 T , the most closely related species, by 19 nucleotide substitutions (3.6% sequence variation) in the D1/D2 region (549 bp compared) and 104 nucleotide substitutions and 44 gaps (27.1% sequence variation) in the ITS region (546 bp compared).