Major Groups > Boletes > Tylopilus

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The Genus Tylopilus  

[ Basidiomycetes > Boletales > Boletaceae . . . ]

by Michael Kuo

A handful of Tylopilus species grow in western North America, but the majority are eastern in distribution. Most are fairly easily distinguished from other boletes by their pinkish pore surfaces--though young specimens in the button stage often have a whitish pore surface, causing confusion with Boletus species, and a handful of species have brown pore surfaces. There is no partial veil, and the spore print is usually pinkish brown to reddish brown, or in some cases chocolate brown. Like almost all boletes, species of Tylopilus are mycorrhizal, involved in important symbiotic relationships with trees.

Taste is an important element in identifying Tylopilus species; some are extremely bitter, while others are mild. Additionally, the stem of a Tylopilus specimen often winds up bearing much of the identification burden: pay special attention to its colors, bruising and/or discoloring, and reticulation (which may be absent, faintly present near the apex, or prominent). Cap color, however, is an extremely variable feature, and many species of Tylopilus go through a bewildering series of color stages during the course of development.

 

Tylopilus rubrobrunneus

Tylopilus indecisus

Tylopilus alboater spore print



Key to Tylopilus in North America

Note, March 2005: I wrote the key below many years ago, and it is not at all satisfactory. The non-dichotomous format is annoying--and, more importantly, it simply doesn't work very well. I will be working on a complete revision at some point in the future. Meanwhile, the brief species descriptions in the key may prove useful--and be sure to check out the keys listed in the references list below.


  • Taste bitter. (1/2)
    • > Found west of the Rocky Mountains, excluding Texas and Mexico. (1/2)

        ° Pore surface whitish, becoming yellowish; stem usually reticulate near apex. (1/2)

        Tylopilus atrofuscus

        ° Pore surface reddish brown to dark brown; stem reticulate or not. (2/2)

          (Note: Some authors place the two mushrooms below in synonymy. Follow the link to Tylopilus porphyrosporus for more information.)

          ~ Medium-sized to large mushroom; growing at lower elevations; flesh bluing on exposure to air. (1/2)

          Tylopilus porphyrosporus
          (At MykoWeb)

          ~ Small to medium-sized mushroom; growing at higher elevations; flesh not bluing on exposure to air. (2/2)

          Tylopilus pseudoscaber
          (At MykoWeb)

      > Found east of the Rocky Mountains, including Texas and Mexico. (2/2)

        ° Stem with a root-like projection underground; known only from New York state. (1/2)

        Tylopilus umbrosus

        ° Not as above. (2/2)

          ~ Young pore surface brown. (1/2)

            + Fresh mushroom with purple to lilac shades present; smell not distinctive. (1/2)

            Tylopilus eximus
            (At Macrofungi of Costa Rica

            + Fresh mushroom without purple or lilac shades; smell pungent (like cloves or tar), base of stem often smelling like chlorine when crushed. (2/2)

              (Note: Some authors place the two mushrooms below in synonymy. Follow the link to Tylopilus porphyrosporus for more information.)

              * Medium-sized to large mushroom; growing at lower elevations; flesh bluing on exposure to air. (1/2)

              Tylopilus porphyrosporus
              (At MykoWeb)

              * Small to medium-sized mushroom; growing at higher elevations; flesh not bluing on exposure to air. (2/2)

              Tylopilus pseudoscaber
              (At MykoWeb)

          ~ Young pore surface not brown (though mature pore surface may be brownish). (2/2)

            + Sliced flesh in cap staining on exposure to air. (1/2)

              * Young cap bright orange to orange-red. (1/2)

              Tylopilus ballouii

              * Not as above. (2/2)

                -- Stem not reticulate, or only minutely so at apex. (1/2)

                  Cap brownish orange to brown, bruising dark brown; stem yellow brown to reddish brown, bruising cinnamon brown to brown; sliced flesh in cap pale pinkish on exposure; spores 8.4-13 x 2-3.5 µ. (1/4)

                  Tylopilus rhodoconius

                  Cap pale to yellow brown or tan to brown, not bruising; stem colored like the cap, not bruising; sliced flesh in cap pale brown on exposure; spores 9-12 x 3-3.5 µ. (2/4)

                  Tylopilus appalachiensis

                  Cap whitish becoming pinkish or tan, developing brown stains; stem white, developing brownish stains; sliced flesh in cap slowly brown on exposure (sometimes taking as much as an hour to manifest); spores 10-15 x 3-5 µ. (3/4)

                  Tylopilus intermedius

                  Cap whitish becoming tan to brownish, bruising cinnamon brown; stem whitish to brownish, sometimes bruising brown; sliced flesh in cap pinkish brown to reddish brown on exposure; spores 7-12 x 2.3-3.5 µ. (4/4)

                  Tylopilus peralbidus

                -- Stem reticulate. (2/2)

                  Cap whitish to pale pinkish tan, developing brown stains; stem to 1.5 cm thick; primarily growing under deciduous trees, but reported under pine. (1/2)

                  Tylopilus intermedius

                  Cap more highly colored, not developing brown stains; stem to 3 cm thick; primarily growing under conifers. (2/2)

                  Tylopilus felleus

            + Sliced flesh in cap not staining on exposure to air. (2/2)

              * Young stem (ignore the cap!) with purple to lilac shades present. (1/2)

                -- Cap bruising rusty purple to dark purple; stem bruising yellow to yellow brown, but without olive discolorations; spores 7-10 x 3-4 µ. (1/2)

                Tylopilus violatinctus
                (At Macrofungi of Costa Rica)

                -- Cap not bruising; stem sometimes bruising olive to olive brown; spores 10-13 x 3-4 µ. (2/2)

                Tylopilus plumbeoviolaceus

              * Young stem without purple to lilac shades. (2/2)

                -- Young cap white to whitish. (1/2)

                  Pore surface slowly bruising brownish; stem reticulate or not, developing yellowish to brownish stains; spores 10-13 x 3-5 µ. (1/3)

                  Tylopilus intermedius

                  Pore surface not bruising; stem reticulate, not bruising; spores 11-13 x 3.5-4.5 µ. (2/3)

                  Tylopilus rhoadsiae

                  Pore surface bruising brown; stem not reticulate, sometimes bruising brownish; spores 7-12 x 2.3-3.5 µ. (3/3)

                  Tylopilus peralbidus

                -- Young cap more highly colored. (2/2)

                  Stem to 3 cm thick, reticulate, brown or whitish, sometimes developing olive stains or bruising olive; pore surface usually bruising brown; spores 11-17 x 3-5 µ. (1/5)

                  Tylopilus felleus

                  Stem to 1.5 cm thick, not reticulate, tawny, not bruising; pore surface not bruising; spores 8-10 x 3.5-4 µ. (2/5)

                  Tylopilus subunicolor

                  Stem to 3 cm thick, not reticulate, pale yellow to gray, sometimes streaked with gray to orange but not bruising; pore surface bruising yellowish to yellow-brown; spores 7.5-11 x 3.5-4.5 µ. (3/5)

                  Tylopilus williamsii

                  Stem to 5 cm thick, not reticulate or only finely so at apex, brown or whitish, usually developing olive stains; pore surface bruising brown; spores 10-14 x 3-4.5 µ. (4/5)

                  Tylopilus rubrobrunneus

                  Stem to 1.5 cm thick, finely reticulate near apex, brown or whitish, not bruising; pore surface not bruising; spores 11-17 x 3-5 µ. (5/5)

                  Tylopilus minor

  • Taste not bitter. (2/2)
    • > Found west of the Rocky Mountains, excluding Texas. (1/2)

        ° Young pore surface brown. (1/2)

          (Note: Some authors place the two mushrooms below in synonymy. Follow the link to Tylopilus porphyrosporus for more information.)

          ~ Medium-sized to large mushroom; growing at lower elevations; flesh bluing on exposure to air. (1/2)

          Tylopilus porphyrosporus
          (At MykoWeb)

          ~ Small to medium-sized mushroom; growing at higher elevations; flesh not bluing on exposure to air. (2/2)

          Tylopilus pseudoscaber
          (At MykoWeb)

        ° Young pore surface not brown (though mature pore surface may be brownish). (2/2)

          ~ Pore surface yellow, bruising blue; stem whitish with reddish dots, not reticulate. (1/2)

          Tylopilus amylosporus
          (At MykoWeb)

          ~ Not as above. (2/2)

            + Cap brown to reddish brown; stem whitish, pink near the base, bruising brown; pore surface white becoming pinkish, bruising brown; cap red with ammonia; spores 8-12 x 3-4 µ. (1/5)

            Tylopilus humilis
            (At MykoWeb)

            + Cap brown to cinnamon brown; stem white, becoming brownish, bruising brown; pore surface white becoming pinkish to pinkish brown, bruising brown; cap blackish brown with ammonia; spores 10-15 x 3-5 µ. (2/5)

            Tylopilus indecisus

            + Cap dark reddish brown; stem brown to reddish brown; pore surface white becoming pinkish, bruising brown; cap with a dark violet flash, then reddish to blackish brown with ammonia; spores 8-13 x 3-5 µ. (3/5)

            Tylopilus ferrugineus
            (see Tylopilus badiceps)

            + Cap purplish brown, becoming drab; stem white, bruising brownish or vinaceous; pore surface white becoming vinaceous buff, bruising brown; cap reaction to ammonia not recorded; spores 8-12 x 3-4 µ. (4/5)

            Tylopilus ammiratii
            (At MykoWeb)

            + Cap sooty black; stem black above, whitish below; pore surface whitish becoming yellowish; cap reaction to ammonia not recorded; spores 11-17 x 4.5-6 µ. (5/5)

            Tylopilus atrofuscus

      > Found east of the Rocky Mountains, including Texas. (2/2)

        ° Easily recognized species: (1/2)

          ~ Young cap bright orange to orange red. (1/6)

          Tylopilus ballouii

          ~ Base of stem and flesh in base of stem bright chrome yellow. (2/6)

          Tylopilus chromapes

          ~ Stem with a root-like projection; known only from New York state. (3/6)

          Tylopilus umbrosus

          ~ Stem slender (to 1 cm thick) and graceful, reddish brown to yellow brown; spores pitted. (4/6)

          Austroboletus gracilis

          ~ Cap dark gray-brown, medium sized; pore surface whitish when young (later brownish), bruising blue then brownish red; stem brownish with greenish or bluish tints near apex, not reticulate. (5/6)

          Tylopilus sordidus

          ~ Flesh white, marbled with transparent areas, slowly staining pinkish when sliced; pore surface whitish becoming pinkish; all parts of the mushroom bruising brownish on handling; cap margin inrolled, with a small sterile portion; stem not reticulate. (6/6)

          Tylopilus rhodoconius

        ° Not as any of the above easily recognized species. (2/2)

          ~ Young pore surface brown or black. (1/2)

            + Pore surface staining greenish blue, then reddish to brownish; smell pungent (like cloves or tar), base of stem often smelling like chlorine when crushed. (1/2)

              (Note: Some authors place the two mushrooms below in synonymy. Follow the link to Tylopilus porphyrosporus for more information.)

              * Medium-sized to large mushroom; growing at lower elevations; flesh bluing on exposure to air. (1/2)

              Tylopilus porphyrosporus
              (At MykoWeb)

              * Small to medium-sized mushroom; growing at higher elevations; flesh not bluing on exposure to air. (2/2)

              Tylopilus pseudoscaber
              (At MykoWeb)

            + Not as above. (2/2)

              * Cap reddish brown, brown, olive brown, grayish, or blackish; pore surface black becoming gray, bruising orange to gray; stem reticulate, black to gray; spores 8-14 x 3-5 µ. (1/4)

              Tylopilus griseocarneus
              (At Macrofungi of Costa Rica)

              * Cap purple brown to grayish or reddish brown; pore surface dark brown to purple brown (sometimes grayish), bruising dark brown; stem not reticulate, colored like the cap; spores 11-17 x 3.5-5 µ. (2/4)

              Tylopilus eximus
              (At Macrofungi of Costa Rica)

              * Cap grayish brown to blackish; pore surface white becoming brown, bruising vinaceous brown to dark brown; stem not reticulate, white above, dark brown to blackish below; spores 9-12.5 x 4-5.4 µ. (3/4)

              Tylopilus atratus

              * Cap yellow brown to orange brown; pore surface white or brown becoming yellow brown to brown, with dark brown stains but not bruising; stem reticulate, colored like the cap; spores 10-17 x 3.5-4.5 µ. (4/4)

              Tylopilus tabacinus

          ~ Young pore surface not brown or black (though mature pore surface may be brownish). (2/2)

            + Stem not reticulate, or merely finely so at apex. (1/2)

              * Sliced flesh in cap not staining on exposure to air (manifestation may be slow!). (1/2)

                -- Stem white to yellow, sometimes with pink shades; cap shaggy, yellowish to pinkish brown; pore surface white becoming pinkish, not bruising; cap brown with ammonia; spores 14-21 x 4-6 µ. (1/5)

                Tylopilus conicus

                -- Stem tawny ochraceous; cap tawny ochraceous; pore surface pale becoming pinkish to brownish; cap reaction to ammonia not recorded; spores 8-10 x 3.5-4 µ. (2/5)

                Tylopilus subunicolor

                -- Stem brown; cap maroon to reddish brown; pore surface white, becoming brownish (without pink shades), bruising brown; cap dark amber with ammonia; spores 6.5-10.5 x 2.5-4 µ. (3/5)

                Tylopilus badiceps

                -- Stem white, becoming brownish, bruising brown; cap brown to cinnamon brown; pore surface white becoming pinkish to pinkish brown, bruising brown; cap blackish brown with ammonia; spores 10-15 x 3-5 µ. (4/5)

                Tylopilus indecisus

                -- Stem white above, dark brown to black below; cap gray brown to blackish; pore surface white, becoming brownish, bruising vinaceous brown to brown; cap reaction to ammonia not recorded; spores 9-12.5 x 4-5.5 µ. (5/5)

                Tylopilus atratus

              * Sliced flesh in cap staining on exposure to air. (2/2)

                Note: The eight mushrooms below can be difficult to separate. Mini-descriptions are provided, with distinguishing features italicized.

                -- Cap maroon and velvety, becoming purplish brown to reddish brown and smooth, fading; pore surface white to brownish (not pinkish), sometimes bruising brown; stem brown, not bruising; flesh white, slowly pinkish brown on exposure; cap amber with ammonia; found under oak; distribution uncertain; spores 6.5-10.5 x 2.5-4 µ. (1/8)

                Tylopilus badiceps

                -- Cap brownish and felty, becoming cinnamon tan, fading; pore surface white becoming pinkish to brownish, bruising brown; stem white becoming pinkish or brownish, bruising brown; flesh white, slowly pinkish or brownish on exposure; cap very dark brown with ammonia; found under deciduous trees or conifers; widley distributed; spores 10-15 x 3-5 µ. (2/8)

                Tylopilus indecisus

                -- Cap olive to brownish gray and velvety, bruising darker, finely cracked in age; pore surface grayish to yellowish becoming grayish to reddish brown, bruising slowly reddish brown or darker; stem colored like the cap, not bruising; flesh white, slowly reddish brown on exposure, then grayish; cap reddish to reddish brown with ammonia; found under deciduous trees or conifers; widely distributed; spores 11-20 x 5-8 µ. (3/8)

                Tylopilus nebulosus

                -- Cap olive brown to brownish and smooth, darkening; pore surface white for some time, then slowly cinnamon to reddish brown, tubes blackish when sliced; stem whitish with black hairs or lines, sometimes grayish to brownish below, black near base (the base typically pointed and root-like), not bruising; flesh white, slowly reddish or pinkish on exposure, then blackish; cap reddish black to black with ammonia; found under oak, beech, or hemlock; range New York to West Virginia; spores 7.5-10.5 x 4-5 µ. (4/8)

                Tylopilus atronicotianus

                -- Cap yellow brown to tan and felty, fading, sometimes cracked in age; pore surface white becoming pinkish, bruising brown; stem colored like the cap or paler, not bruising; flesh whitish to pale yellow, pale brown on exposure; cap reaction to ammonia not recorded; found under deciduous trees; eastern Canada to Georgia; spores 9-12 x 3-3.5 µ. (5/8)

                Tylopilus appalachiensis

                -- Cap black to dark brown, with a white bloom, velvety; pore surface white or grayish, becoming pinkish, usually bruising reddish then slowly black; stem colored like the cap or paler, not bruising; flesh white, becoming pinkish, then blackish on exposure; cap negative with ammonia; found under deciduous trees (especially oak); widely distributed; spores 7-11 x 3.5-5 µ. (6/8)

                Tylopilus alboater

                -- Cap dark reddish brown, smooth or felty; pore surface whitish becoming pinkish, bruising brown; stem brown to reddish brown, not bruising; flesh white, becoming pinkish, then brownish on exposure; cap with a violet flash, then reddish to blackish brown with ammonia; found under oak; widely distributed; spores 8-13 x 3-5 µ. (7/8)

                Tylopilus ferrugineus
                (see Tylopilus badiceps)

                -- Cap gray brown to blackish brown, velvety and cracked; pore surface white but soon brown, bruising vinaceous brown to dark brown; stem blackish to brownish, densely and finely hairy, not bruising; flesh white, slowly and irregularly blackish on exposure (not pinkish); cap reaction to ammonia not recorded; found under hemlock; known from western New York; spores 9-12.5 x 4-5.5 µ. (8/8)

                Tylopilus atratus

            + Stem reticulate. (2/2)

              * Cap flashing vinaceous to violet with ammonia, then settling to reddish brown, blackish brown, or orange (but see also Tylopilus appalachiensis below, for which chemical reactions are not recorded). (1/2)

                -- Cap yellow brown to orange brown; mature pore surface brownish with darker stains but not bruising; spores 10-17 x 3.5-4.5 µ. (1/2)

                Tylopilus tabacinus

                -- Cap dark reddish brown; mature pore surface pinkish, bruising brown; spores 8-13 x 3-5 µ. (2/2)

                Tylopilus ferrugineus
                (see Tylopilus badiceps)

              * Cap reaction to ammonia not as above. (2/2)

                -- Cap maroon to reddish brown; pore surface white for some time, becoming brownish (without pink shades), often bruising brown; stem brown; cap dark amber with ammonia; spores 6.5-10.5 x 2.5-4 µ. (1/4)

                Tylopilus badiceps

                -- Cap brown to cinnamon brown; pore surface white becoming pinkish to pinkish brown, bruising brown; stem white becoming brownish; cap blackish brown with ammonia; spores 10-15 x 3-5 µ. (2/4)

                Tylopilus indecisus

                -- Cap olive brown becoming brownish; pore surface white becoming brownish pink, bruising pinkish brown; stem white above, brown below; cap reddish brown to orange brown with ammonia; spores 9-13 x 3-4.5 µ. (3/4)

                Tylopilus variobrunneus

                -- Cap yellow brown to brown or tan; pore surface white becoming pinkish, bruising brown; stem colored like the cap or paler; cap reaction to ammonia not recorded; spores 9-12 x 3-3.5 µ. (4/4)

                Tylopilus appalachiensis



    (References used for this page can be found in the reference list for boletes.)



    Cite this page as:

    Kuo, M. (2005, March). The genus Tylopilus. Retrieved from the MushroomExpert.Com Web site: http://www.mushroomexpert.com/tylopilus.html



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