Unveiling Species Diversity Within Early-Diverging Fungi from China XIII: Four New Species of Absidia (Cunninghamellaceae, Mucoromycota)

The genus <i>Absidia</i> is predominantly distributed in soil habitats. During the fungal investigation of soil collected from China (Guangxi, Yunnan, and Chongqing), four novel species of <i>Absidia</i> were identified, namely <i>Absidia brunneola</i> sp. nov., <i>A. digitata</i> sp. nov., <i>A. exilis</i> sp. nov., and <i>A. tumida</i> sp. nov. This identification was based on morphological characteristics and molecular analyses of the internal transcribed spacer (ITS), small subunit (SSU) and large subunit of ribosomal RNA gene (LSU rDNA), actin gene (ACT), and translation elongation factor 1-alpha gene (TEF1α). <i>Absidia brunneola</i> sp. nov. is sister to <i>A. jiangxiensis</i>, which is characterized by the production of light brown sporangia. <i>Absidia digitata</i> sp. nov. and <i>A. tumida</i> sp. nov. are sister to each other with the former species developing digitiform rhizoids and the latter swollen in sporangiophores. <i>Absidia exilis</i> sp. nov. is closely related to <i>A. oblongispora</i>, exhibiting poorly developed sporangiophores. To date, the total number of recognized species within the genus <i>Absidia</i> has increased to 66, including the four new ones herein.