Anchoring the species Rhizophagus intraradices (formerly Glomus intraradices )

The nomenclatural type material of (basionym ) was originally described from a trap pot culture established with root fragments, subcultures of which later became registered in the INVAM culture collection as FL 208. Subcultures of FL 208 (designated as strain ATT 4) and a new strain, independently isolated from the type location (ATT 1102), were established as both pot cultures with soil-like substrate and root organ culture. Long-term sampling of these cultures shows spores of the species to have considerable morphological plasticity, not described in the original description. Size, shape and other features of the spores were much more variable than indicated in the protologue. Phylogenetic analyses confirmed earlier published evidence that sequences from all cultures formed a monophyletic clade, well separated from, and not representing a sister clade to, . Moreover, new phylogenetic analyses show that and are synonymous. The morphological characters used to separate these species exemplify the difficulties in species recognition due to the high phenotypic plasticity in the genus is morphologically re-described, an epitype is designated from a single-spore isolate derived from ATT 4, and is synonymised with .