A new genus, Desertispora, and a new species, Diversispora sabulosa, in the family Diversisporaceae (order Diversisporales, subphylum Glomeromycotina)

Abstract

Phylogenetic analyses of sequences of the SSU–ITS–LSU nrDNA segment and the RPB1 gene showed that the arbuscular mycorrhizal fungus originally described as Diversispora omaniana does not belong to the genus Diversispora, but represents a separate clade at the rank of genus in the family Diversisporaceae of the order Diversisporales. The closest natural relatives of the fungus proved to be species of the genera Corymbiglomus and Redeckera. Consequently, the new genus was named Desertispora, and Di. omaniana was renamed De. omaniana comb. nov. In addition, the morphological and histochemical features of spores and mycorrhizal structures of a new Diversispora sp., Di. sabulosa, were described and the closest relatives of the species were determined based on phylogenetic analyses of sequences of the two loci mentioned above. The new fungus was grown in single-species cultures established from spores extracted from a trap culture inoculated with a mixture of the rhizosphere soil and root fragments of Ammophila arenaria that had colonized maritime sand dunes of the Curonian Spit located in the north of Lithuania. Diversispora sabulosa was never found before in many different sites of the world which were sampled during the last 34 years by the last author of the paper. Also, the lack of molecular sequences in public databases of identity ≥ 97% to sequences of Di. sabulosa suggests that the fungus is rare on the Earth.