Glomus corymbiforme, a new species in Glomales from Poland

Glomus corymbiforme sp. nov. is described and illustrated. This fungus was found associated with roots of different plant species colonizing maritime sand dunes adjacent to Swinoujscie in northwestern Poland. Glomus corymbiforme is distinctive in forming corymbiform sporocarps with spores enveloped individually by a hyphal mantle composed of dichotomously branched hyphae. Spores are pastel yellow to orange, globose to subglobose, (50-) 142 (-220) μm in diameter or ovoid to pyriform, 110-125 × 120-200 μm. Spore wall structure consists of an outermost unit wall tightly adherent to a middle laminated wall and of a separable innermost membranous wall. Glomus corymbiforme produced spores and vesicular-arbuscular mycorrhizae in single-species pot cultures with Sorghum vulgare.