In Pteropspora the association is with a very limited number of fungi in the genus Rhizopogon, including Rhizopogon subcaerulescens, R. arctostaphyli, and R. salebrosus.
R. luteolus was deliberately introduced into Pinus radiata plantations in Western Australia to improve tree growth in the early part of the 20th century.
Rhizopogon subcaerulescens | Rhizopogon | Rhizopogon vinicolor |