Pavement Mushroom Agaricus bitorquis
The Pavement Mushroom is a remarkable thing, receiving its name from a remarkable ability to punch its way through tarmac and lift paving stones. We think of mushrooms as fragile things, but the compact nature of this mushroom, plus the power or hydraulic pressure, enables it t0 achieve such feats with seeming ease.
It is always a compact species with dense flesh and a conspicuous double-ring on the stem - hence its Latin name. The spores are dark brown.
It is found only occasionally, and mostly where one would expect to find it - growing through tarmac paths in towns. One wonders where it made a living before tarmac was invented.
It has a pleasant flavour, similar to that of shop-bought mushrooms (Agaricus bisporus), but like an old rooster or geriatric sheep, the flesh can be a bit tough.