Imperator rhodopurpureus

Description

Imperator rhodopurpureus is an inedible fungus of the genus Imperator, found under deciduous trees including oak and beech in neutral soils. The cap is cushion-like, up to 20 cm in diameter; faint yellow- or pink-buff when young, later flushing red from the rim and becoming blotched with yellow, red, and olivaceous tones. The tubes are orange or red at first, then turn dark blue when cut. The spores are olive-brown. The stem is rather short, and sometimes very bulbous. The flesh is pale yellow, turning blue when cut.

Initially described as Boletus rhodopurpureus, it was transferred to the new genus Imperator in 2015. The bolete is considered critically endangered in the Czech Republic.

Poisonous when raw or undercooked. In literature, it is positioned as inedible or poisonous.

Mushroom Identification

1. Cap

   5 to 20 cm in diameter, spherical, then convex, the edges are slightly wavy. The skin is velvety, dry, in wet weather slightly mucous, slightly tuberculate. It is unevenly colored: on a grayish or olive-gray background, red-brown, reddish, wine, or pink zones, covered with dark blue spots when pressed. Often eaten by insects, yellow flesh is visible in places of damage. The tubular layer is lemon-yellow, then greenish-yellow, the pores are small, blood-red or orange-red, dark blue when pressed.

2. Spores

   10.5-13.5 * 4-5.5 microns.

3. Spore Print

   Olive or olive-brown.

4. Stem

   6-15 cm high, 2-7 cm in diameter, first tuberous, then cylindrical with club-shaped thickening. The color is lemon-yellow with a dense reddish mesh, blackish-blue when pressed.

5. Flesh

   The flesh is firm at a young age, lemon-yellow, when damaged, it instantly becomes black-blue, then after a long time, it acquires a wine hue. The taste is sweetish, the smell is sour-fruity, weak.

6. Habitat and Distribution

   Prefer calcareous soils, more often lives in hilly and mountainous areas. It is found in broad-leaved and mixed forests next to beeches and oaks. Fruits in June-September.

Synonyms

1. Boletus rhodopurpureus Smotl.

2. Boletus xanthopurpureus (Smotl.) Hlaváček

3. Boletus rhodopurpureus f. xanthopurpureus Smotl.

Photo sources:

Photo 1 - Author: GLJIVARSKO DRUSTVO NIS from Serbia (CC BY-SA 2.0)

Photo 2 - Author: Davide Puddu (Davide Puddu) (CC BY-SA 3.0)

Photo 3 - Author: Xth-Floor (CC BY-SA 3.0)

Photo 4 - Author: (Gerhard Koller) (CC BY-SA 3.0)