Amanita retenta - Amanitaceae.org - Taxonomy and Morphology of Amanita and Limacella
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name Amanita retenta
name status nomen acceptum
author Yang-Yang Cui, Qing Cai & Zhu L. Yang
intro This text is derived from the original description of Amanita retenta.  The fruiting bodies of Amanita retenta are small to medium-sized.
cap The cap is 30 – 70 mm wide, plano-convex to planar, dirty white, grayish, gray, gray-brown to brown, occasionally pure white.  Volva is often present as large, white patches slightly attached on the cap.  The cap’s margin is radially grooved covering 15% - 40% of the cap's radius.  There is no material hanging from the edge.  The flesh is white.
gills The gills are free, crowded, and white.  The short gills are truncate and plentiful.
stem The stem is 70 – 110 × 4 – 15 mm, nearly cylindrical or narrows upwards, white, dirty white to brownish, covered with minute, concolorous, snake-like squamules.  The stem lacks a basal bulb.  At the stem's base, the volva is saccate, 10 – 40 × 10 – 20 mm, membranous, and both the inner and outer surfaces are white to dirty white.
odor/taste The odor and taste were not recorded for the present species.
spores The spores measure 10.0 – 12.0 × 9.5 – 11.5 µm and are globose to subglobose and inamyloid.  There are no clamps at the bases of basidia.
discussion Amanita retenta is described from Yunnan Province, China.  It is found in pine or mixed forests.

Note that because there are abundant inflated cells in the outer part of the volva on the stem’s base, the volva can easily be broken during the development of the fruiting body.

Specimens of A. retenta with entirely white fruiting bodies have also been collected in the field.  The white fruiting bodies of A. retenta could be misidentified as the European A. vaginata var. alba Gillet.  For example, HKAS 82591 was treated as A. vaginata var. alba by Yang (2015) and should be a species of A. retenta based on molecular evidence in Cui et al. (2015).  Additionally, A. vaginata var. alba differs from the white fruiting bodies of A. retenta by the absence of patches on the cap, and the irregularly distributed, brownish spots on the outer surface of the volva on the stem’s base.—Yang-Yang Cui and Rachel Warner
brief editors RET

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