Racocetra undulata , a new species in the Glomeromycetes from Taiwan

A new arbuscular mycorrhizal fungus, Racocetra undulata (Racocetraceae: Glomeromycetes), was found in soil samples collected from the rhizosphere of two coastal plants, Hibiscus tiliaceus and Pandanus odoratissimus var. sinensis, at depths of 0-20 cm in western Taiwan in October 2007. The 195-225 mu m broad, globose to subglobose, pale yellow glomerospores, which form terminally on sporogenous cells, have an undulate wall surface and two walls. The germination shields on the outer surface of the inner wall are ovoid, hyaline to subhyaline, with folds separating wavy lobes. The undulate outer spore surface readily differentiates R. undulata from all other Racocetra species.