Type: Mycorrhizal Fungi; Description: Basidiomata hypogeous, globose, subglobose or lobed, concolorous with the substrate, 10–40 mm in diameter; peridium composed of three layers: the exoperidium comprising a complete case formed from particles of the surrounding substrate (e.g., sand, soil, or litter) tightly bound into a hard, black layer by pigmented hyphae; the mesoperidium consisting of a network of the tree rootlets embedded in hyaline hyphae; and the endoperidium forming a creamy white layer not penetrated by rootlets from the mesoperidium. Gleba olivaceous to smoky grey, powdery at maturity; capillitium threads hyaline, unbranched; core concolorous with the endoperidium, occupying about half of the glebal cavity; attached by a few widely spaced, flattened tuberculae about 2 mm thick. Basidiospores elliptical, 0-septate, 8–13 × 4–6 μm, mostly smooth but occasionally finely warted, hyaline but faintly tinted in mass, with or without a short pedicel.

Distribution: Coromandel, Waikato, Bay of Plenty, Taupo.

Significance: The intimate and invariable association of mature fruiting bodies with tree roots and the presence of a partial Hartig net are indications that M. glauca is an obligate ectomycorrhizal fungus (Beaton & Weste 1983). No investigation of its mycorrhizal relationships has been carried out in New Zealand. Fruiting bodies develop underground to a depth of 30 cm or more and are exposed by animals that dig them up. Wild pigs seem to be particularly attracted to Mesophellia. In Eucalyptus plantations on pumice soils in the central North Island, large areas resembling ploughed fields are occasionally seen where pigs have been rooting for the fruiting bodies. NEW ZEALAND RECORD OF PLANT ASSOCIATION: Chu-Chou & Grace (1982: as Mesophellia arenaria).; Host(s): Eucalyptus delegatensis, E. fastigata, E. regnans, E. saligna.