LAUSR

Abstract Mucor species are common fast-growing fungi found in soil. Two new species of Mucor and one new geographical record of M.nederlandicus were collected from northern Thailand and are described in this study. Evidence from morphophysiological data and phylogenetic analysis supports the introduction of the new taxa. Phylogenetic analysis based on the internal transcribed spacer (ITS) and large subunit of the nuclear ribosomal RNA (LSU) data showed that the new isolates cluster distinctly from other Mucor species with high or maximum bootstrap support. Mucoraseptatophorus is characterized by aseptate sporangiophores, globose columella, resistant and deliquescent sporangia, has sympodial, and monopodial branches and shows growth at 37 °C. It also differs from M.irregularis in having smaller sporangiospores, and larger sporangia. Mucorchiangraiensis has subglobose or slightly elongated globose columella, produces hyaline sporangiospores, and resistant and deliquescent sporangia. Furthermore, this species has wider sporangiophore, smaller sporangia and lower growth than M.nederlandicus. A detailed description of the species and illustrations are provided for the novel species.