Name: Boletus dupainii
Citation: Bull. Soc. mycol. Fr. 18: 139 (1902)
Preferred Synonyms:Rubroboletus dupainii (Boud.) Kuan Zhao & Zhu L. Yang
Cap: 5-10 cm across; convex, becoming broadly convex or nearly flat; sticky when fresh; bald; shiny when dry, and often with adhering leaves or debris; bright red (sometimes with a pinkish margin), fading somewhat with age; when fresh bruising dark blue; staining waxed paper yellow.
Pore Surface: Initially deep red to bright orangish red, with deep yellow marginal areas; becoming orangish brown to olive; bruising promptly dark blue or nearly black; 3-4 round pores per mm; tubes to 8 mm deep.
Stem: 5-9 cm long; 1-2 cm thick; more or less equal; not reticulate; yellow, decorated with fine red flecks and scales that are more densely packed towards the base; bright yellow at the apex; bruising blue; basal mycelium white, bruising dark purplish red.
Flesh: Pale yellow in the cap; deep bright yellow to red in the stem; bluing when sliced.
Odor and Taste: Odor not distinctive; taste slightly acetic, or not distinctive.
Chemical Reactions: Ammonia negative to yellow on cap surface; negative to yellow or orangish on flesh. KOH negative to orange or dull, pale olive on cap surface; negative to orangish on flesh. Iron salts negative to grayish or olive gray on cap surface; negative on flesh.
Dried Specimens: Caps retain the bright red shade for several years, but after about 10 years become dull brownish red.
Spore Print: Olive.
Microscopic Features: Spores 10-13 × 3-5 µ; smooth; subfusiform; yellow in KOH. Hymenial cystidia inconspicuous; hyaline in KOH; fusoid-ventricose to fusiform; to about 35 µ long. Pileipellis a cutis of hyphae 2-4 µ wide; golden yellow in KOH (but after about 10 years of preservation merely yellowish or nearly hyaline); terminal elements cylindric with rounded apices.
Created: 2012-03-29 12:10:38 CST (+0800) by Noah Siegel (Noah)
Last modified: 2015-02-03 09:26:25 CST (+0800) by Erlon (Herbert Baker)
Viewed: 198 times, last viewed: 2019-05-23 19:32:31 CST (+0800)