Context white or yellowish white, especially under the crust,
perhaps pale tawny above the hymenophore. Crust on the pileal surface dark chestnut brown to blackish. Pileus 6-io
cm. diam. Rare, on certain conifers, particularly Taxus
G. valesiacum (Boud.)Pat.
Spores measure 9-11(-12) x 5.7-8 (lo-5 X 7) t, Q= 1-5, and are
consistently broadly ovoid with a strongly curved abaxial surface, and a
slightly convex adaxial surface,lacking any suprahilardepression.The species is generally regarded as a close relative of G. lucidum,and the structure of
the spore wall supports this view. Under the light microscope the orna- mentation appears coarser than in G. lucidumwith the echinulae sometimes
aggregated into small groups. Surface replicas and scanning electron micro- graphs reveal a perisporial coat which covers the entire spore, except for the apical fragmentation, and numerous circular holes are observed which tend to be larger than those found in G. lucidum.The openings, 0-3-0o9 /L diam., are randomly distributed and vary from 30-60 in number on a single
spore. In the adaxial suprahilar region the underlying exosporial echinules are more widely separated and there is sometimes a small fragmented peri-
sporial region suggesting an indistinct suprahilar plage. The truncated apical region is often broader, 2-3 ptdiam., than in G. lucidum.Treatment with chromic acid removes most of the perisporium although remnants invariably remain attached to the apices of the exosporial echinules. Echinules are basically columnar, terete in section, but variable in length, 0-3-1 o0 long, thus some are not fused with the perisporial membrane. The large echinules are apically inflated and fused both with the ecto-perisporium and with adjacent apices. There is some evidence of occasional low connectionsjoining adjacent echinules but the pattern is never truly reticulate. The hilar
appendix remains very small, rarely protruding beyond the perisporium, and is scarcely visible under the light microscope.
Inanumberofsporesanopening 1-3~diam.,whichappearstopenetrate the exo-episporium, has been observed. Fig. 1/2; pl. 21.
SPECIMEN EXAMINED: Surrey, Cheam, 13 July 1971, Bennett.
Created: 2010-05-15 20:24:21 PDT (-0700) by Erlon (Herbert Baker)
Last modified: 2018-03-21 03:42:09 PDT (-0700) by Chaelthomas (Chaelthomas)
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