Boletus eastwoodiae (Murrill) Saccardo and Trotter
This is the California version of the Satan's Bolete. It is found mainly under Live Oak (Quercus agrifolia), but also appears under Pacific Madrone (Arbutus menziesii) . As noted by MykoWeb "common in some years, rare in others."  The history of that name is rather messy. 

Collection under Pacific Madrone (Arbutus menziesii)
Listed as poisonous, but quite popular with the deer:

Murrill put the name Boletus eastwoodiae on dried specimen that was sent to him in the NYBG by Alice Eastwood of the CAS. Then for many years it was assumed that what we call today B. pulcherrimus is B. eastwoodiae. In 1976 Thiers & Halling  studied the type collection and determined with high probability that it contained the Californian  B. satanas. Then a later paper by Arora, Ferrarese & Simonini (1999) solidified that name.