| Amanita
sororcula Tulloss, Ovrebo & Halling "Little Sister Ringless Amanita"
Technical description (t.b.d.) BRIEF DESCRIPTION: The cap of Amanita sororcula is 35 - 60 mm wide, bell-shaped at first, eventually nearly flat, sometimes with an umbo, with margin striate (25 - 35% of the radius). The cap ranges from gray to grayish brown and is paler toward the margin. The flesh is white, but black under the cap skin. The cap is 4 - 5 mm thick. The volva is present in scattered patches that are white to tannish gray. The gills are free, ranging from white to gray or dark brownish gray with age, and 6 - 7.5 mm broad. The stem is 70 - 150 x 7 - 10 mm, white, sometimes gray toward base, exannulate, and decorated with fine, appressed gray to brownish gray fibrils. The flesh is white and hollow. The volva may be sac-like, membranous to submembranous, white to gray, extending up to 30 mm from the bottom of the stem, or it may be in scattered gray patches or bands on the lower stem; in the latter cases, there may also be a white cup surrounding the stem base. The spores measure (7.8-) 9.5 - 14.0 (-17.0) x (7.2-) 8.8 - 12.8 (- 15.5) µm and are globose to subglobose (occasionally broadly ellipsoid) and inamyloid. Clamps are not present or rare at bases of basidia. Amanita sororcula is known from Costa Rica to Andean Colombia, where it occurs in cloud forest with oak. Prior to description of A. sororcula, collections of this species were commonly assigned to A. ceciliae (Berk. & Broome) Bas, which also has a weakly structured volva and graying gills, but, among other differences, the latter has a strong yellow tint in the pileus when young. As far as is known, A. ceciliae is restricted to Europe and neighboring regions of Asia. Several Western Hemisphere species with a weakly structured volva and graying lamellae remain to be formally described. -- R. E. Tulloss Photos: R. E. Tulloss (Costa Rica, specimens in photo on left are over mature) Return to Section Vaginatae page. Last changed 17 August
2004. |
