Queen Bolete (Boletus aereus, B. regineus): Edible (choice!) Boletus aereus is another prized mushrooms in Europe (a.k.a. Porcino Nero), and it was thought to be the same species as Boletus regineus found in California. The cap is dark brown to black when young, but then fades to reddish-brown often with white blotches. Cap size: 2.0-5.9 inches (5-15 cm), but can get to7.9 inches (20 cm). Found growing solitary or scattered and in groups under mixed woods, but especially with oaks.