Amanita basibulbosa

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

The cap of Amanita basibulbosa is up to 85 mm wide, convex then plane, smooth somewhat innately radially fibrillose, dry, pale gray, with a nonstriate margin.  Volval remains are present as abundant conical warts, pyramidal at the center, smaller towards the margin, sometimes absent with age, and gray, darker than the cap.

The gills are free, crowded, thin, white to pale cream, with a concolorous edge.  The short gills are present in at least two series.

The stem is up to 130 × 10 mm, white, with finely granular surface in the lower part.  The ring is persistent, membranous, white, and striate above.  The bulb is globose and prominent, not abrupt, white, with several rings or zones of volval material at approximately the point where the stem widens into the bulb.

The spores measure (7.1-) 8.4 - 9.6 (-10.6) × (6.8-) 7.4 - 9.6 µm and are subglobose to broadly ellipsoid and amyloid.  Clamps are present at bases of basidia.

Wood describes the mushroom as occurring in sclerophyll forests and "tall open 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).

The present species was originally placed in section Validae by its author, however, as in the cases of Amanita elongatispora A. E. Wood, A. cinerascens A. E. Wood, and A. griseoconia D. A. Reid, the proper placement for A. basibulbosa is in section Lepidella.

In using Bas' (1969) keys, the present species can certainly be placed with confidence in Amanita subsect. Solitariae Bas; within that subsection, it is, perhaps, most similar to taxa of stirpes Virginea and Daucipes.  Stirps Virginea is defined in part as having warts comprised almost entirely of inflated cells that somehow bind tightly to each other without interweaving hyphae.  In stirps Daucipes, inflated cells dominant the tissue but there are filamentous hyphae noticeably present.  The volva of A. basibulbosa is described as dominated by inflated cells with some filamentous hyphae.  The illustration of Wood chooses to emphasize the presence of hyphae to the degree that they seem equally plentiful with the inflated cells.  The situation requires revision of the original material.  In an exchange with our co-editor, Dr. Zhu L. Yang, he advised that we not try to draw too many conclusions from the presently limited available data.—R. E. Tulloss and L. Possiel