Amanita javanica

The following is based on Corner & Bas (1962) and Boedijn (1951).

The cap of A. javanica is 60 - 85 mm wide, orange yellow to ochre-yellow, sometimes with a reddish brown tinge, antique brown to maize yellow to raw sienna between orange and xanthene orange to yellow ochre in the center, gradually changing towards the margin to light cadmium to between apricot yellow and empire yellow to light orange yellow or deep chrome, strongly convex at first, later plano-convex, umbonate, with a sulcate-striate margin (about 50% of the radius). The flesh is off-white, 4 - 6 mm thick above the stem, and rapidly thinning to a membrane.

The gills are free, yellow in side view, orange yellow in mass, and 8 - 12 mm broad.

The stem is 90 - 130 × 10 - 14 mm, narrowing upward, yellow (for example, near apricot yellow), decorated with orange buff scales.  The ring is 20 - 30 mm from the top of the stem, skirt-like, hanging loosely, orange buff, and finely striate on the upper surface.  The saccate volva is off-white, 20 - 50 × 30 - 35 mm and up to 3 mm thick.

Spores measured by Boedijn 8 - 12 × 6 - 8 µm and are ellipsoid and inamyloid.  Clamps are present at bases of basidia.  Spores measured by RET from Japanese material are as follows: (9.2-) 10 - 13 (-16) × (6.5-) 7.2 - 8.2 (-10) µm.

This species was originally described from Java.  The species currently widely reported from southeast Asia (Japan, China, Nepal, and northern India); however, RET and ZLY have reservations concerning whether the mainland material is indeed the same species as A. javanica (see below).  In Japan, the species reported as A. javanica occurs in pine-oak forests (Pinus densiflora and Quercus serrata).  No associated plants were mentioned by Boedijn.

The present species is placed in Amanita stirps Hemibapha.

It was mentioned above that the editors of these pages have some concern over whether species reported as A. javanica in China and Japan are indeed the same as the entity described by Boedijn.  The mainland material has spores as follows: (8.5-) 9.0 - 12.5 (-16.0) × (6.3-) 6.5 - 8.5 (-10.0) µm and are broadly ellipsoid to ellipsoid, rarely elongate.  In this entity, the umbo is often the same color as the cap's margin, and the cap is often described as entirely "golden yellow."  This golden yellow Slender Caesar is seasonally common in some markets in Yunnan Province, China.  Unfortunately, as far as we are aware, all known illustrations purporting to show the present species show, instead, the mainland entity. —R. E. Tulloss and L. Possiel

The editors of this site owe a great debt to Dr. Cornelis Bas whose famous cigar box files of Amanita nomenclatural information gathered over three or more decades were made available to RET for computerization and make up the lion's share of the nomenclatural information presented on this site.

[ Keys & Checklists ]
[ Draft description of, & key to, sect. Caesareae ]

[ Keys & Checklists ]
[ Draft description of, & key to, sect. Caesareae ]