Galerina marginata
This mushroom contains the same deadly toxins as some
Amanita mushrooms and must be avoided.  Fruits year round
in warm, wet weather.  
Galerina marginata produces a rusty
brown spore print; grows on wood.  Also known as
, a former name.
The spores of Galerina marginata feature a plage;
a smooth, flat impression at one end.  
"One of the deadliest mushrooms on the
planet...", is how Michael Kuo describes
Galerina marginata at MushroomExpert.Com.
See Galerina autumnalis at
Fungi Growing on Wood