Amanita morenoi : Moreno's Amanita

Technical description (t.b.d.)


Amanita morenoi is a poorly known species. It has a cap 45 – 63 mm wide as dried, pale brown to sordid chestnut brownAmanita morenoi when fresh, polished, convex when young, and planar in age. The cap margin is apparently nonstriate at first, then short tuberculate-striate. The volva appears on the cap as warts, densest over disc, large, thick, subpyramidal to conical, crowded, brown, and pulverulent.

The gills of this species are free or narrowly adnate, rather close, and cream to white. The short gills are truncate to subtruncate to rounded truncate with attenuate tooth and apparently sparse.

The stem is 68 – 71 x 8 – 10 mm as dried and cream when fresh; and the stem’s bulb is 15 – 20 x 14 – 16 mm as dried, possibly subglobose or even subabrupt when fresh; and is hollow as dried in some specimen. There is an membranous, superior, skirt-like annulus that collapses on the stipe. On the stipe the volva is pulverulent brown to chestnut brown and forms scales and warts on lower stipe and the top of the bulb, sometimes warts may be in a ring.

Odor and taste were not recorded for this species as far as we know.

The spores of this species measure (8.4-) 8.8 – 12.2 (-19.6) x (7.0-) 7.5 – 10.5 (-15.4) µm and are subglobose to broadly ellipsoid to ellipsoid (or infrequently globose) and inamyloid. Clamps are rather common at the bases of basidia.

Amanita morenoi is found only in Argentina in the area of Lago Espejo in Parque Nacional Nahuel Huapí, in March. If there is a very similar taxon (none are known, the common clamps suggest a possible relationship to the A. muscaria-group), that entity probably also occurs only in the Southern Hemisphere. Specimens of this species have been misdetermined as A. umbrinella E. J. Gilbert & Cleland, which is a very dark capped Australian taxon.

The species may be toxic and likely to produce symptoms similar to those of A. muscaria (L.:Fr.) Pers. and A. pantherina. — R. E. Tulloss