1. Pileus <15 cm in diam when mature.................................................................................................................................................2

1. Pileus> 15 cm in diam when mature.................................................................................................................................................5

2. Hymenophore changing to dark blue when injured, then dingy orange-yellow or olive................................................. B. alexandri

2. Hymenophore changing to blue when injured....................................................................................................................................3

3. Pileus grayish red, grayish rose, reddish gray, reddish brown, a distribution in Asia............................................. B. pseudocalopus

3. Pileus darker, deep apple red, pinkish red, brick red to brownish red, a distribution in North America...........................................4 4. Cap colored with deep vinaceous red that slowly fades to dull ochraceous with red splashes, and stipe context golden yellow..................................................................................................................................................................................................... B. bicolor

4. Cap colored with a mottled brick red to brownish red, and stipe context paler yellow............................................. B. rufomaculata

5. Basidiospores with Q m> 2.60, distribution in temperate areas...................................................................................... B. emileorum

5. Basidiospores with Q m <2.60, distribution in tropical areas..............................................................................................................6

6. Basidiomata larger when mature (up to 23 cm), basidiospores shorter but wider [(6–)7.5–9(–10) × (4–)4–5(–5.5) µm] with Q m = 2.52, cheilocystidia smaller (21–37 × 11.5–15 µm)............................................................................................................... B. major

6. Basidiomata smaller when mature (up to 17 cm), basidiospores longer but narrower [7.5–11.5(–12.5) × 3.5–5 µm] with Q m = 2.24, cheilocystidia larger (39.5–63.5 × 16.5–23 µm)....................................................................................................... B. duplicatopora