Amanita pallidochracea

The following is largely based on the original description (Wood 1997).

The cap of Amanita pallidochracea is up to 40 mm wide, pale biscuit color, convex then plano-convex, smooth, dry, faintly virgate, with a reportedly nonstriate and nonappendiculate margin. Volval remains are absent or limited to one irregular, flat, off- white, membranous patch.

The gills are free, crowded, thin, white to slightly off- white, with a concolorous and finely serrate edge. Short gills are reportedly absent.

The stem is up to 50 × 7 mm, cylindric to slightly narrowing upward, white above, deep cream below, with irregular fine bundles of fibers  covering it. No ring is present.  The base is slightly enlarged [?}, with a large, white, membranous, saccate volva.

The spores measure (8.3-) 9.7 - 10.8 × 5.1 - 6.6 µm and are elongate and inamyloid. Clamps are absent at bases of basidia.

Wood describes the mushroom as occurring in sclerophyll forests from the state of New South Wales, Australia. A sclerophyll forest in the Australian bush is a forest of hard-leaved plants including Eucalyptus in the overstory (wikipedia). So far as we know this species is known only from the type collection.

Wood describes the spores of the present species as having an average length to width ratio slightly in excess of 1.8. For section Vaginatae, these are extremely narrow spores. In a discussion of spore shape variation in the world, Tulloss (2005) noted the very few species in section Vaginatae having spores this narrow and the fact that they are limited (as far as is known) to three widely separated areas on the planet: Nigeria (one species with a weak ring), Florida (two species, one with a ring, one without), and New South Wales (one species lacking ring). There is no reason to believe that these four taxa are closely related either phenetically or phylogenetically. 

The confusion surrounding the occasionally utilized section Ovigerae Singer (a synonym of section Vaginatae) is provided with another example in Wood's treatment of it.  He places an annulate member of the Vaginatae, an exannulate member of the Vaginatae (the present species), and an exannulate member of section Amanita all in section Ovigerae.—R. E. Tulloss and L. Possiel