Xerocomellus atropurpureus
Fungal Systematics and Evolution 6: 276. 2020.
Common Name: none
Misapplied names: Boletus zelleri Murrill; Ceriomyces zelleri Murrill; Xerocomus zelleri (Murrill) Snell; Xerocomellus zelleri (Murrill) Klofac
Cap 4-11 cm broad, convex, nearly plane at maturity; brown to blackish-brown, velvety, smooth to uneven, with a whitish bloom when young, occasionally aereolate in age; flesh pallid to yellowish, sometimes bruising blue.
Pores small, pallid, becoming yellowish-green, often (but not always) bruising blue.
Stipe 5-10 cm long, 1-3 cm thick, more or less equal, dry, reddish over a yellow ground color, usually yellow at the base.
Spores 11-15 x 4-6 µm, smooth, fusiform (spindle-shaped). Spore print olive-brown.
Solitary or in small groups from early fall to mid-winter under conifers, particularly Douglas fir and coast redwood.
Edible and good, but often infected with fly larvae.
This handsome bolete is most easily recognized by examining young material which has a blackish-brown velvety cap, yellowish pores that occasionally bruise blue, and a reddish stipe. Xerocomellus chrysenteron is similar but the cap is not as dark and tends to crack at maturity. Xercomellus mendocinensis is similar with pores and context staining quickly and intensely blue. Xerocomellus zelleri is morphologically very similar but is rare in California and uncommon in the Pacific Northwest.
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