I took the following specimen:
This shows red bleeding where it has been bruised, which is a characteristic of S. gausapatum.
This specimen yielded the following spores (magnification x600, field width 86um):
These are about 8 x 4um which agrees reasonably well with the range of 7-8 x 3-3.5um given for S. gausapatum at RogersMusrooms.com.
First photo and specimen taken in the Wilderness, Whiteknights Park, Reading, UK, on 2013-12-30.