180 · Boletes of Eastern North America Genus Bu t yr ibolet us Arora & J. L. Frank The genus Butyriboletus was erected in 2014 to accommodate species formerly classified in the genus Boletus, section Appendiculati, commonly known as the “butter boletes.” The name Butyriboletus means “butter bolete.” The genus presently contains fourteen species from Asia, Europe, North Africa, and North America. Three species are known to occur in eastern North America. Molecular data and macroscopic features place this group in a clade separate from Boletus sensu stricto. Species in this genus have a yellow tube layer that often bruises blue, a yellow reticulate stalk, and firm, yellow-tinged flesh that may or may not turn blue when exposed. Butyriboletus brunneus (A)
Butyriboletus · 181 Butyriboletus brunneus (Peck) Arora & Frank = Boletus speciosus var. brunneus Peck = Boletus pseudopeckii A. H. Sm. & Thiers Common name(s): Showy Reddish Brown Bolete Overview: Butyriboletus brunneus is one of the earliest boletes to appear in spring, often in early June. It is an excellent edible species, although the flesh is often riddled with insect larvae or eaten by slugs, so unblemished specimens are not often found. The term brunneus means “reddish brown,” a reference to this handsome bolete’s cap color. Cap: 4–14 cm wide, convex, becoming broadly convex to nearly plane in age, margin incurved at first, even; surface dry, glabrous or nearly so, reddish brown or yellow brown to olive brown; flesh pale yellow, quickly staining blue when exposed; odor and taste not distinctive. Pores and tubes: bright yellow to yellow when fresh, becoming dull yellow to olive yellow in age, instantly staining blue when bruised, depressed at the stalk; tubes 8–22 mm deep. Stalk: nearly equal or enlarged downward, solid; surface dry, finely reticulate overall or at least over the upper half, yellow on the upper portion, pinkish red to purplish red or at least tinged reddish on the lower portion, especially near the base, staining blue when bruised; flesh concolorous with the cap flesh or deeper yellow, staining like the cap flesh when exposed. Butyriboletus brunneus (B)
182 · Boletes of Eastern North America Habitat and season: solitary, scattered, or in small groups under broadleaf trees or conifers, especially hemlock, or in mixed woods; late spring, summer, and fall. Distribution and frequency: eastern Canada south to North Carolina, west to Minnesota; occasional to fairly common. Spore print: olive brown. Microscopic features: spores 10–15 × 3–5.5 µm, narrowly oblong to subfusoid, smooth, ochraceous. Edibility: edible and excellent. Lookalikes: Boletus speciosus (p. 155) is very similar but has a bright rose-red to rose-pink cap that becomes pinkish with olive tones or pinkish brown to olive brown at maturity. Alessioporus rubriflavus (p. 56) has a dark wine-red cap when young that becomes olive to brownish olive with red streaks and splashes at maturity, conspicuous reticulation over at least the upper half of the stalk, dark wine-red flesh near the stalk base, and larger spores. Butyriboletus peckii (Frost) K. Zhao, Z. L. Yang & Halling = Boletus peckii Frost = Caloboletus peckii (Frost) Vizzini Common name(s): Peck’s Bolete Overview: The species name honors American mycologist Charles H. Peck (1833–1917). For an interesting account of how this bolete may have been described, see Both 1993. The key identification features include the somewhat velvety reddish cap, whitish to pale-yellow flesh that stains slightly blue, yellow pores that stain blue and then brownish, and a red stalk that is typically reticulate overall. Cap: 2.5–9.5 cm wide, convex, becoming broadly convex to nearly plane at maturity, margin with a narrow band of sterile tissue when young, becoming even with maturity; surface dry, somewhat velvety, deep red to dull red Butyriboletus peckii
Butyriboletus · 183 or rose red, fading to brownish rose or pale tan to buffy brown from the disc outward; flesh whitish to pale yellow, staining slightly and sometimes slowly blue when exposed, burgundy red around larval tunnels; odor not distinctive; taste variously described as unpleasant, somewhat bitter, or tart. Pores and tubes: bright yellow to golden yellow at first, becoming dingy olive yellow to brownish yellow in age, staining blue and then slowly brownish when bruised; tubes 4–15 mm deep. Stalk: enlarged downward to nearly equal, solid; surface dry, minutely and densely pruinose, rosy red to darker red or purplish red overall or with yellow at the apex, sometimes with olive or brownish tinges near the base, typically reticulate nearly overall or at least on the upper portion, basal mycelium whitish to pale yellow; flesh concolorous with and staining like the cap flesh. Habitat and season: scattered or in groups in broadleaf forests and mixed woods, especially with beech and oak, summer and fall. Distribution and frequency: eastern Canada south to Georgia, west to Tennessee and Indiana, distribution limits yet to be established; occasional. Spore print: ochraceous brown. Microscopic features: spores 10–14 × 3.5–4 µm, ellipsoidal, smooth, yellowish. Edibility: unknown. Lookalikes: The Baorangia bicolor complex (p. 74) is very similar but lacks reticulation on the stalk or is rarely reticulate only at the apex. Butyriboletus roseopurpureus (A)
184 · Boletes of Eastern North America Butyriboletus roseopurpureus (Both, Bessette & Roody) K. Zhao, Z. L. Yang & Halling = Boletus roseopurpureus Both, Bessette & Roody Common name(s): none. Overview: The term roseopurpureus means “pinkish purple,” a reference to this bolete’s cap color. Except for the cap color, this mushroom is all yellow. The flesh and pores stain rapidly blue when cut or bruised. The stalk, which also bruises blue, is conspicuously reticulate. When NH4OH is applied to the cap, it produces a dingy pale-yellowish to dull-orange stain. Cap: 7–15 cm wide, convex, becoming broadly convex to nearly plane in age, margin incurved at first, later decurved, projecting as a sterile band of tissue; surface viscid-tacky in wet weather but drying quickly, somewhat velvety or covered with matted fibers, strikingly pinkish purple when fresh, becoming darker purplish pink to dark purplish red, at times mottled in these colors, marginal areas becoming grayish in age; flesh pale yellow, instantly staining dark blue when exposed but soon fading to pale-slate color; odor fragrant; taste very sour, like lemon. Pores and tubes: lemon yellow or more golden at first, becoming yellowish olive to greenish olive at maturity, instantly staining dark blue to greenish Butyriboletus roseopurpureus (B)
Caloboletus · 185 blue when bruised, soon fading to pale greenish blue or greenish gray; tubes 5–10 mm deep. Stalk: equal or slightly tapered downward; reticulate nearly the entire length or at least over the upper two-thirds, sometimes strongly raised, covered with tiny matted fibers on the lower portion, bright yellow nearly overall, occasionally with burgundy-red areas near the base, with a white base and a white basal mycelium, instantly staining dark blue when bruised; flesh deep yellow, sometimes burgundy red in the basal area, instantly staining blue when exposed but soon fading to a pale-slate color. Habitat and season: solitary or in small groups in mixed woods of oak, beech, hemlock, and maple, apparently associated with red oak; summer and early fall. Distribution and frequency: New England south to Florida, distribution limits yet to be established; occasional. Spore print: light brownish olive. Microscopic features: spores 9.4–13 × 2.7–3.5 µm, narrowly ellipsoid to subfusoid, smooth, pale ochraceous in Melzer’s. Edibility: unknown. Lookalikes: This Bolete may have been misidentified in the past as Boletus speciosus Frost (p. 155). However, Charles Frost described the cap color of his species as “scarlet lake red,” a bright red without purplish tones. In addition, the spores of Boletus speciosus are longer and wider, 11–15 × 3–5.5 µm. Boletus rubissimus A. H. Sm. (not illustrated) is similar to Butyriboletus roseopurpureus but differs sharply in the weak or absent blue staining of its exposed flesh, a poorly developed reticulum on the stalk, yellow mycelium at the stalk base, and shorter, somewhat broader spores, 9–11 × 3–4 µm. Genus Calobolet us Vizzini The genus Caloboletus was erected in 2014 to accommodate species formerly classified in the genus Boletus. The name Caloboletus is derived from the Greek word calo, which means “beautiful or nice,” a reference to the pinkish or reddish tinges on the stalks of most of the species in the genus. The genus includes ten species worldwide, four of which occur in eastern North America. Species in this genus often have whitish to grayish caps and yellow pores and tubes. The exception is Caloboletus firmus, which has orange to red pores when young and whitish to yellow flesh that usually stains blue and tastes bitter. This genus has been supported by molecular analysis.
186 · Boletes of Eastern North America Caloboletus calopus (Pers.) Vizzini = Boletus calopus Pers. = Boletus calopus var. frustosus (Snell & E. A. Dick) O. K. Mill. & Watling = Boletus frustosus Snell & E. A. Dick Common name(s): Bitter Beech Bolete, Scarlet-stemmed Bolete Overview: The common name “Bitter Beech Bolete” is a bit misleading because this species occurs primarily with hemlock in northeastern North America. The term calopus means “beautiful foot,” a reference to this handsome bolete’s stalk. Cap: 6–20 cm wide, rounded when young, becoming convex to broadly convex in age, margin incurved at first, with a narrow band of sterile tissue; surface dry, somewhat velvety, becoming nearly smooth at maturity, slightly to conspicuously cracked in age, light brown to grayish brown or olive brown at first, becoming paler olive brown to dark yellow brown as it ages; flesh whitish to pale yellow, rapidly staining blue when exposed; odor somewhat pungent or not distinctive; taste bitter. Pores and tubes: pale yellow at first, becoming olive yellow to brownish yellow at maturity, rapidly staining blue when bruised, typically depressed at the stalk in age; tubes up to 2 cm deep. Stalk: nearly equal or enlarged downward, sometimes with a pinched base, solid; surface dry, scurfy-punctate or nearly smooth, yellowish toward the apex, carmine red to nearly scarlet below, often reddish brown toward the base, typically staining blue when handled or bruised, conspicuously reticulate at least over the upper portion or sometimes nearly overall, reticulation Caloboletus calopus
Caloboletus · 187 rarely inconspicuous or lacking; flesh concolorous with and staining like the cap flesh. Habitat and season: solitary, scattered, or in groups in conifer woods, especially with hemlock or spruce, or less often in broadleaf woods with beech or oak, usually found at higher elevations; summer and fall. Distribution and frequency: eastern Canada south to New England and New York, west to Michigan, distribution limits yet to be established; uncommon. Spore print: olive brown. Microscopic features: spores 13–17(19) × (3)4.5–6 µm, ellipsoidal, smooth, yellowish; tube trama septa amyloid in Melzer’s reagent. Edibility: unknown but probably not edible because of the bitter-tasting flesh. Lookalikes: Caloboletus inedulis (p. 191) is typically smaller. It has a whitish to grayish-white or sometimes pale pinkish-gray cap that darkens to olivaceous brown and pale grayish brown in age, paler-pinkish to pinkish-red coloration on its stalk, and smaller spores that measure 9–13 × 3.3–4.5 µm; the septa of its tube trama are not amyloid in Melzer’s reagent. The photograph of Boletus roseipes (A) = Caloboletus roseipes (Bessette, Both & A. R. Bessette) Vizzini is mislabeled in North American Boletes (Bessette, Roody, and Bessette 2000, 308). It should be Caloboletus calopus. Caloboletus roseipes (p. 192) has an olive-brown to grayish-brown cap when young that becomes pale grayish brown to grayish tan on older specimens. Its stalk is bright yellow near the apex, with rosy-red or yellow with rosy-red areas below, and it has smaller spores. Caloboletus firmus (A)
Caloboletus firmus (B) Caloboletus firmus (C)
Caloboletus · 189 Caloboletus firmus (Frost) Vizzini = Boletus firmus Frost = Boletus piedmontensis Grand & A. H. Sm. = Boletus satanas var. americanus Coker & Beers Common name(s): Piedmont Bolete Overview: The term firmus means “firm,” a reference to this bolete’s sturdy, dense flesh, especially when it is young and fresh. The whitish to grayish, tan, or pale grayish-olive cap, whitish flesh that stains blue when exposed, red to red-orange pores that bruise blue, and the red reticulation on the stalk are its distinctive features. Cap: 6–15 cm wide, convex, becoming broadly convex in age, margin even, inrolled when young; surface dry, glabrous but appearing finely velvety, whitish to grayish, grayish brown, tan, pinkish tan, or pale grayish olive; flesh firm, whitish to pale yellow, staining blue when exposed, sometimes slowly or slightly; odor wax-like or not distinctive; taste mild to slightly bitter. Pores and tubes: pinkish at first, soon becoming red or red orange, staining blue when bruised or bruising yellow on very young specimens; tubes 8–20 mm deep. Stalk: nearly equal or tapered in either direction, solid; surface dry, nearly smooth, concolorous with the cap, sometimes with reddish tints, staining olive to brownish when handled or bruised, with fine red reticulation near the apex or nearly overall or sometimes completely lacking; flesh concolorous with and staining like the cap flesh or tinged pinkish near the base. Habitat and season: solitary, scattered, or in groups under broadleaf trees, especially oak and beech; late spring, summer, and fall. Distribution and frequency: eastern Canada south to Georgia, west to Mississippi; occasional. Spore print: olive brown. Microscopic features: spores 9–15 × 3.5–5 µm, subellipsoid, smooth, yellowish. Edibility: inedible because of the bitter taste. Lookalikes: Both Caloboletus inedulis (p. 191) and Caloboletus roseipes (p. 192) are similar, but they have yellow pores and red areas on their stalks.
Caloboletus inedulis (A) Caloboletus inedulis (B)
Caloboletus · 191 Caloboletus inedulis (Murrill) Vizzini = Boletus inedulis (Murrill) Murrill = Boletus subclavatipes subsp. inedulis (Murrill) Singer = Ceriomyces inedulis Murrill Common name(s): Rosy-footed Oak Bolete Overview: The term inedulis means “not edible,” a reference to this bolete’s bitter-tasting flesh. The key identification features include a whitish to grayish cap, whitish to yellowish flesh that stains blue, yellow pores that stain blue, and a reticulated yellow stalk with red tinges. Cap: 4–12 cm wide, convex, becoming broadly convex to nearly plane in age, margin incurved to inrolled at first, remaining so well into maturity, with a narrow band of sterile tissue; surface dry, covered with tiny, cottony, matted fibers at first, becoming conspicuously cracked, with whitish flesh showing in the fissures, color whitish to grayish white or pale pinkish gray, sometimes with pinkish-rose areas especially toward the margin, darkening to olivaceous brown to pale grayish brown in age; flesh whitish to yellowish, staining blue when exposed; odor not distinctive; taste bitter. Pores and tubes: pale yellow, becoming olive yellow at maturity, staining dark blue and then brownish when bruised, depressed at the stalk in age; tubes 8–16 mm deep. Stalk: nearly equal or slightly enlarged downward, solid; surface dry, pale yellow to yellow, at times with a pinkish zone at the apex or pinkish to pinkish red below, staining blackish brown near the base when handled, with reddish or brownish reticulation at least on the upper portion; flesh concolorous with and staining like the cap flesh. Habitat and season: scattered or in groups in broadleaf or mixed woods, associated with oak, hickory, hemlock, or spruce; summer and fall. Distribution and frequency: widely distributed throughout eastern North America; infrequent. Spore print: olive brown. Microscopic features: spores 9–13 × 3.3–4.5 µm, subfusoid, smooth, ochraceous; tube trama lacking amyloid septa. Edibility: inedible. Lookalikes: Caloboletus roseipes (p. 192) is similar but has an olive-brown to grayish-brown cap when young that becomes pale grayish brown to grayish tan on older specimens, a thicker stalk, and different macrochemical test reactions, and it is associated with hemlock. Caloboletus calopus (p. 186) is typically larger, with an olive-brown to gray-brown cap that darkens to dark yellow brown in age, darker-red coloration on its stalk, and larger spores that measure 13–19 × 5–6 µm.
192 · Boletes of Eastern North America Caloboletus roseipes (Bessette, Both & A. R. Bessette) Vizzini = Boletus roseipes Bessette, Both & A. R. Bessette Common name(s): Rosy-footed Hemlock Bolete Overview: The term roseipes means “rosy foot,” a reference to the rosy-red coloration on this bolete’s stalk. The key identification features include an olive-brown to grayish-tan cap, white to pale-yellow flesh that stains blue, yellow pores that stain blue, and a yellow stalk with red areas. Cap: 4–12 cm wide, convex, becoming broadly convex to nearly plane in age, margin incurved at first and remaining so well into maturity, with a narrow band of sterile tissue; surface dry, somewhat velvety at first, becoming appressed-tomentose and somewhat cracked in age, olive brown to grayish brown when young, becoming pale grayish brown to grayish tan on older specimens; flesh white to pale yellow, staining blue when exposed; odor not distinctive; taste bitter. Pores and tubes: pale yellow, becoming olive yellow to brownish yellow at maturity, staining blue when bruised; attached or slightly depressed at the stalk; tubes 5–16 mm deep, concolorous with and staining like the pores. Stalk: enlarged downward to a pinched base or nearly equal, solid; surface dry, scurfy-punctate nearly overall, bright yellow near the apex, rosy red or yellow with rosy-red areas below, staining blue when bruised, Caloboletus roseipes
Chalciporus · 193 reticulation reddish and variable, distinct on the upper portion of some specimens and absent on others; flesh concolorous with and staining like the cap flesh. Habitat and season: scattered or in groups under hemlock or in mixed woods with hemlock and spruce; summer and fall. Distribution and frequency: eastern Canada south to New England and New York, distribution limits yet to be established; infrequent. Spore print: olive brown. Microscopic features: spores 10–14 × 3–4.5 µm, narrowly oblong to subfusoid, smooth, ochraceous in KOH or Melzer’s, lacking an apical pore; tube trama lacking amyloid septa. Edibility: inedible because of the bitter taste. Lookalikes: Caloboletus calopus (p. 186) is similar but has a darker-brown cap, a darker-red stalk with prominent reticulation, and larger spores. The photograph of Boletus roseipes (A) = Caloboletus roseipes (Bessette, Both & A. R. Bessette) Vizzini in North American Boletes (Bessette, Roody, and Bessette 2000, 308) is mislabeled and should be Caloboletus calopus. Caloboletus inedulis (p. 191) is also similar but has a whitish to grayish-white or pale pinkish-gray cap that becomes darker brown and conspicuously cracked in age and is associated with oaks. Genus Ch alciporus Bataille The genus Chalciporus was erected in 1908 to accommodate species formerly classified in several genera, including Boletus and Suillus. The name Chalciporus means “copper-colored pores,” a reference to the color of the mature pores. The genus has less than ten species described from North America. They are small- to medium-size terrestrial boletes with mature pores that are pinkish, reddish, dull ocher to yellow brown, cinnamon, or orange to reddish brown. Their stalks are solid and smooth, often with bright-yellow mycelium at the base. Spore-print colors include yellow brown, cinnamon brown, brown, rusty cinnamon, and dark smoky olive.
Chalciporus piperatus Chalciporus piperatoides (A)
Chalciporus · 195 Chalciporus piperatus (Bull.) Bataille = Boletus piperatus Bull. Common name(s): Peppery Bolete Overview: The term piperatus means “peppery.” The combination of a brownish cap, a stalk with bright-yellow mycelium at the base, and peppery-tasting flesh makes this small bolete easy to recognize. Cap: 1.6–9 cm wide, convex, becoming nearly plane in age, margin even; surface smooth, dry or somewhat viscid, sometimes cracked in age, buff to yellow brown, orange brown, or reddish brown; flesh pale yellow or tinged reddish, becoming dingy purplish brown in age, not staining blue when cut or bruised; odor not distinctive; taste bitter, hot and peppery. Pores and tubes: attached to slightly depressed, with small angular pores that sometimes appear to radiate from the stalk, dull cinnamon, reddish cinnamon, or cinnamon brown, becoming darker reddish brown in age, sometimes staining brown when cut or bruised; tubes 3–10 mm deep. Stalk: equal or tapered downward, solid; surface dry, concolorous with the cap or paler, with a bright-yellow basal mycelium; flesh lemon yellow, unchanging when cut or exposed. Habitat and season: solitary, scattered, or in groups under conifers or broadleaf trees; spring, summer, and fall. Distribution and frequency: widely distributed; fairly common. Chalciporus piperatoides (B)
196 · Boletes of Eastern North America Spore print: brown to cinnamon brown. Microscopic features: spores 9–12 × 4–5 µm, narrowly fusiform, smooth, pale brown. Edibility: unknown. Lookalikes: Chalciporus piperatoides (A. H. Sm. & Thiers) T. J. Baroni & Both (see photos, p. 194) is nearly identical, but its pores quickly bruise blackish blue. Chalciporus rubinellus (p. 198) has a broadly conical cap, pinkish-red pores that do not bruise blue, and mild-tasting flesh. Chalciporus pseudorubinellus (A. H. Sm. & Thiers) L. D. Gomez = Boletus pseudorubinellus A. H. Sm. & Thiers Common name(s): none. Overview: The term pseudorubinellus means “false rubinellus” in reference to this bolete’s similarity with Chalciporus rubinellus (p. 198). The key identification features include the variable yellowish or pinkish-red cap, pale-yellow flesh that does not stain when exposed, bright rose-red pores, and a rose-pink stalk with a yellow base. Cap: 1.5–6 cm wide, convex to broadly convex, sometimes broadly umbonate, margin even; surface dry, glabrous or nearly so, color variable, yellowish or pinkish red, becoming pinkish cinnamon in age; flesh pale yellow, not staining blue when exposed; odor and taste not distinctive. Pores and tubes: bright rose red when fresh, fading to orangish or yellowish brown in age, not staining blue when bruised; tubes 6–10 mm deep. Stalk: nearly equal or enlarged downward, solid; surface dry, finely pruinose, mostly rose pink, typically yellow near the base, with yellow basal mycelium; flesh concolorous with the cap flesh. Chalciporus pseudorubinellus
Chalciporus · 197 Habitat and season: scattered or in groups in conifer woods, often among mosses; summer and fall. Distribution and frequency: New England and New York west to Minnesota, distribution limits yet to be established; occasional. Spore print: brown. Microscopic features: spores 9–13 × 3–4 µm, fusoid, smooth, distinctly olivaceous. Edibility: unknown. Lookalikes: Chalciporus rubinellus (p. 198) has a redder cap, especially when immature, lacks yellow mycelium at the stalk base, and has larger spores, 12–15 × 3–5 µm. Chalciporus rubritubifer (p. 199), known only from the Myakka River State Park in Florida, has a dark orange-yellow cap when young that becomes orange brown to reddish brown at maturity, grayish-red to dull-red pores that become brownish orange to copper in age, and a stalk that is concolorous with the cap or paler, with a sparse pale-yellow basal mycelium. Chalciporus rubinellus (A)
198 · Boletes of Eastern North America Chalciporus rubinellus (Peck) Singer = Boletus rubinellus Peck = Suillus rubinellus (Peck) Singer Common name(s): Purple-red Bolete Overview: The Purple-red Bolete is one of the smallest of the eastern boletes and the only one in the genus that lacks even a hint of yellow at the stalk base. The term rubinellus means “somewhat red” or “reddish,” alluding to this bolete’s overall colors. The cap surface stains blood red and then dingy orange with NH4OH. Cap: 2–4.5 cm wide, broadly conical when young, becoming convex in age, margin even; surface dry, somewhat velvety when young, becoming cracked in age, red or reddish when young, more yellow in age; flesh bright yellow, not staining blue when exposed; odor and taste not distinctive. Pores and tubes: bright rose red when young, becoming dull rose red to rose pink in age, not staining blue when bruised; tubes 6–10 mm deep. Stalk: nearly equal, solid; surface dry, initially red or reddish, sometimes mixed with yellow, lacking yellow mycelium at the base; flesh concolorous with the cap flesh. Habitat and season: solitary, scattered, or in groups in mixed woods or conifer forests; summer and fall. Chalciporus rubinellus (B)
Chalciporus · 199 Distribution and frequency: eastern Canada south to North Carolina, west to Minnesota; occasional. Spore print: brown. Microscopic features: spores 12–15 × 3–5 µm, subfusoid, smooth, pale dull ochraceous. Edibility: unknown. Lookalikes: Chalciporus pseudorubinellus (p. 196) has a less-red cap, especially when immature; yellow mycelium at the stalk base and smaller spores, 9–13 × 3–4 µm. Chalciporus rubritubifer (p. 199), known only from the Myakka River State Park in Florida, has a dark orange-yellow cap when young that becomes orange brown to reddish brown at maturity, grayish-red to dull-red pores when young that become brownish orange to copper in age, and a stalk that is concolorous with the cap or paler, with a sparse pale-yellow basal mycelium. Chalciporus rubritubifer (Kauffman) Singer = Boletus rubritubifer Kauffman Common name(s): none. Overview: The term rubritubifer means “red or reddish tubes,” a reference to the color of this bolete’s tubes and pores. The cap surface stains reddish brown with KOH or NH4OH. Cap: 1.3–5 cm wide, hemispherical to convex, becoming broadly convex in age, margin incurved at first, sometimes with a narrow band of sterile tissue; surface dry, somewhat velvety, becoming finely cracked in age with yellow flesh showing in the fissures, dark orange yellow and staining brown when Chalciporus rubritubifer
200 · Boletes of Eastern North America young, becoming reddish brown to orange brown at maturity; flesh yellow, sometimes with grayish or orange hues, showing a reddish line or zone above the tube layer, not staining blue when exposed; odor and taste not distinctive. Pores and tubes: grayish red to dull red when young, becoming brownish orange to copper at maturity, attached to slightly depressed at the stalk, not staining blue when bruised; tubes 2–5 mm deep. Stalk: tapered downward or nearly equal, often curved near the base, solid; surface dry, faintly longitudinally striate to finely punctate, concolorous with the cap or paler yellow, usually reddish at the apex, becoming dark reddish brown at the base, with a sparse pale ochraceous-yellow basal mycelium; flesh concolorous with the cap flesh. Habitat and season: solitary, scattered, or in groups under oaks, pines, and palms; summer and fall. Distribution and frequency: known only from the Myakka River State Park in Florida; occasional. Spore print: yellow brown. Microscopic features: spores 9–18 × 4–6 µm, ellipsoidal to subfusoid, smooth, yellowish. Edibility: edible, with good flavor, according to the late Florida mycologist Robert S. Williams (1939–2014). Lookalikes: Chalciporus pseudorubinellus (p. 196) has a yellowish or pinkish-red cap when young that becomes pinkish cinnamon in age, lacks yellow basal mycelium, and is northern in distribution. Chalciporus rubinellus (p. 198) has a red to reddish cap when young that becomes more yellowish at maturity, a stalk with yellow mycelium at the base, and a northern distribution. Genus Cyanobolet us Gelardi, Vizzini & Simonini The genus Cyanoboletus was erected in 2014 to accommodate three species formerly classified in the genus Boletus, one of which occurs in eastern North America. Species in this genus have yellow flesh that instantly discolors dark indigo blue to blackish blue when exposed. The name Cyanoboletus is derived from the Greek word cyano, which means “blue,” a reference to the color reaction of the exposed flesh. This genus is supported by molecular analysis.
Cyanoboletus pulverulentus (A) Cyanoboletus pulverulentus (B)
202 · Boletes of Eastern North America Cyanoboletus pulverulentus (Opat.) Gelardi, Vizzini & Simonini = Boletus pulverulentus Opat. Common name(s): none. Overview: The most apparent identifying feature of this small, dark bolete is that all parts quickly stain dark blue when handled or bruised. Also, the cap surface displays a green flash with the application of NH4OH. The term pulverulentus means “dusty or powdery,” a reference to this bolete’s cap, which often appears to be lightly coated with a layer of dust or powder. Cap: 4–12.5 cm wide, convex, becoming broadly convex to nearly plane in age, margin even; surface dry, somewhat dusty or powdery and slightly velvety at first, becoming glabrous and often somewhat shiny in age, dark yellow brown to blackish brown or dark cinnamon brown, often developing reddish tints in age, instantly staining blackish blue when bruised or handled; flesh yellow, instantly staining blue when exposed; odor and taste not distinctive. Pores and tubes: yellow when young, darkening to golden yellow and then to brownish yellow at maturity, instantly staining dark blue and then dull brown when bruised; tubes 6–12 mm deep. Stalk: nearly equal or sometimes enlarged downward, solid; surface dry, pruinose at the apex, yellow on the upper portion and darker orange yellow on the lower portion, typically reddish brown and pruinose toward the base, at first quickly staining dark blue and then slowly to dull brown when handled, often with raised longitudinal ridges; flesh reddish brown in the base, yellow above the base, instantly staining blue when exposed. Habitat and season: scattered or in groups under conifers or broadleaf trees; summer and fall. Distribution and frequency: widely distributed throughout eastern North America; occasional. Spore print: dark olive to olive brown. Microscopic features: spores 11–15 × 4–6 µm, fusoid to ellipsoidal, smooth, yellowish. Edibility: edible. Lookalikes: Boletus oliveisporus (p. 127) is similar but typically is larger in size, and its fulvous to cinnamon-brown cap does not show a green flash reaction with NH4OH. Genus Exsudoporus Vizzini, Simonini & Gelardi The genus Exsudoporus was erected in 2014 to accommodate three species that have pores often beaded with yellow drops when specimens are young and fresh and that were formerly classified in the genus Boletus. The term exsudoporus means “exuding droplets from the pores.” Species in this genus have red to
Exsudoporus · 203 reddish-brown, dry to slightly viscid caps, reddish-orange to dark-red or rarely yellow-orange pores, conspicuously reticulate stalks, yellow flesh that quickly stains dark blue when exposed, and an olive-brown spore print. Molecular analysis shows that they are closely related. Exsudoporus floridanus (A) Exsudoporus floridanus (B)
204 · Boletes of Eastern North America Exsudoporus floridanus (Singer) Vizzini, Simonini & Gelardi = Boletus floridanus (Singer) Murrill = Boletus frostii ssp. floridanus Singer = Suillellus floridanus (Singer) Murrill Common name(s): none. Overview: The term floridanus means “Florida,” a reference to the location where this bolete was originally collected. The red cap, yellowish flesh that rapidly stains blue, red pores that stain blue when bruised, and red stalk with red reticulations are the diagnostic features of this strikingly beautiful bolete. The cap surface stains olive black with NH4OH. Cap: 4–15 cm wide, convex, becoming broadly convex to nearly plane in age, margin incurved at first, even or nearly so; surface dry, somewhat velvety, pinkish red, rose red, purplish red, or brownish red, typically yellowish or whitish along the margin; flesh pale to bright yellow, quickly staining dark blue when exposed; odor and taste not distinctive. Pores and tubes: color variable, reddish orange to pinkish red, sometimes with yellowish tints, or yellow overall with reddish tints, often beaded with yellow drops when young and fresh, usually depressed at the stalk at maturity, rapidly staining blue; tubes 6–12 mm deep. Stalk: often bulbous when young, usually club-shaped or sometimes nearly equal at maturity, solid; surface dry, typically yellow at the apex and red below or sometimes red overall, with conspicuous longitudinally elongated red reticulation at least over the upper half; flesh pale to bright yellow, quickly staining dark blue when exposed. Habitat and season: scattered or in groups in sandy soil under oaks; summer and fall, also winter in the southern part of its range. Distribution and frequency: Tennessee and the Coastal Plain of North Carolina south to Florida, west to Texas. Spore print: olive brown. Microscopic features: spores 13–18 × 4–5 µm, ellipsoidal to subfusiform, smooth, pale yellow brown. Edibility: edible but of very poor quality. Lookalikes: Exsudoporus frostii (p. 205) has darker-red coloration overall and much coarser, raised reticulation.
Exsudoporus · 205 Exsudoporus frostii (J. L. Russell) Vizzini, Simonini & Gelardi = Boletus frostii J. L. Russell Common name(s): Frost’s Bolete Overview: This is one of the most beautiful and distinctive boletes in eastern North America. The combination of a shiny, candy-apple-red cap, dark-red pores that exude golden moisture droplets when fresh, and a deeply lacerate-reticulate stalk is unmistakable. The species name honors Charles C. Frost (1805–1880), a Vermont shoemaker turned mycologist who was the first to describe several North American species of boletes. Cap: 5–15 cm wide, rounded to convex, becoming broadly convex to nearly plane in age, margin incurved and even when young; surface smooth, shiny, dry or tacky when moist, deep blood red to candy-apple red, often with a narrow yellow band at the margin, sometimes developing yellowish areas in age; flesh pale yellow to dull white, quickly staining blackish blue when exposed; odor not distinctive; taste sour, acidic. Pores and tubes: dark red at first, becoming paler red in age, often exuding golden moisture droplets when young, instantly staining blackish blue when bruised, depressed at the stalk at maturity; pores minute; tubes 6–15 mm deep. Stalk: nearly equal or enlarged downward, often curved at the base, solid; surface dry, dark red to pinkish red with a white to yellowish base, staining Exsudoporus frostii
206 · Boletes of Eastern North America blackish blue when handled or bruised, coarsely and deeply reticulate over the entire length. Habitat and season: solitary to scattered or in groups in broadleaf or mixed woods, especially with oak; summer and fall. Distribution and frequency: widely distributed throughout eastern North America; occasional to locally fairly common. Spore print: olive brown. Microscopic features: spores 11–17 × 4–5 µm, ellipsoidal to subfusiform, smooth, pale brown. Edibility: edible, with a pronounced lemony flavor. Although most people can consume this bolete without negative effects, there are reports of gastrointestinal upset from eating it. Lookalikes: Exsudoporus floridanus (p. 204) is similar but has a lighter-red cap and less-prominent reticulation on its stalk. Genus Frostiella Murrill The genus Frostiella was erected in 1942 to accommodate two species formerly classified in various genera, including Boletellus, Boletus, Ceriomyces, and Suillus. The name Frostiella honors Vermont mycologist Charles C. Frost (1805–1880). Two species—Frostiella betula and Frostiella russellii, which have fairly small caps on long, deeply grooved, and shaggy stalks that lack a partial veil or ring— were formerly assigned to this genus, but Frostiella betula has now been transferred to the genus Heimioporus, leaving only a single species. Frostiella russellii was formerly classified in the genus Boletellus, but molecular studies have shown that it does not belong there. Frostiella russellii (A)
Frostiella · 207 Frostiella russellii (Frost) Murrill = Boletellus russellii (Frost) E. J. Gilbert = Boletus russellii Frost Common name(s): Russell’s Bolete Overview: Although not often encountered, this tall and stately bolete is easy to recognize by its dry, velvety to scaly brown cap and deeply grooved and shaggy stalk. The cap surface stains reddish with NH4OH and olive gray with FeSO4. The flesh stains reddish with KOH and blackish blue with FeSO4. The name russellii honors John Lewis Russell (1808–1873), American botanist and friend of Charles C. Frost, who named this distinctive bolete after him. Cap: 3–13 cm wide, rounded to convex, becoming broadly convex, margin strongly incurved and even; surface dry, velvety when young, becoming cracked or forming scale-like patches as it ages, yellow brown to reddish brown, cinnamon brown, or olive gray; flesh pale yellow to yellow, often brownish around larval tunnels, not staining blue when exposed but sometimes slowly staining brown; odor and taste not distinctive. Pores and tubes: yellow to greenish yellow, unchanging or becoming brighter yellow when bruised, typically somewhat depressed at the stalk at maturity; tubes up to 2 cm deep. Frostiella russellii (B)
208 · Boletes of Eastern North America Stalk: up to 20 cm long, equal or enlarging slightly downward, solid, often curved at the base; surface dry, often viscid at the base when moist, reddish brown to pinkish tan, deeply grooved and ridged for most or all of its length, branched or torn ridges creating a honeycomb or shaggy-bark effect; flesh concolorous with the cap flesh. Habitat and season: solitary or scattered on the ground and on humus under oak, hemlock, or pine; summer and fall. Distribution and frequency: eastern Canada south to Florida, west to Michigan; uncommon. Spore print: dark olive to olive brown. Microscopic features: spores 15–20 × 7–11 µm, ellipsoidal, longitudinally striate with deep grooves or wrinkled with a cleft in the wall at the apex, pale brown. Edibility: edible. Lookalikes: Heimioporus betula (p. 219) is somewhat similar but has a glabrous, shiny, red to orange cap and pitted spores. Genus Gyroporus Quél. The genus Gyroporus was erected in 1886 to accommodate species formerly classified in the genus Boletus. Gyroporus is a fairly small genus with less than a dozen species reported from North America. The name Gyroporus means “round pores.” These species are small- to medium-size terrestrial boletes with dry caps that are typically somewhat velvety to floccose-scaly. Their stalks are hollow or have several cavities at maturity. They have white to pale-yellow flesh that is brittle and stains blue in some species and white to yellow, tiny, round pores. Their spore-print colors include pale to bright yellow or buff. Gyroporus castaneus (A)
Gyroporus · 209 Gyroporus castaneus (Bull.) Quél. = Boletus castaneus Bull. Common name(s): Chestnut Bolete Overview: The Chestnut Bolete is fairly common, especially in central and northern woodlands, but it is easily overlooked owing to its small size and somewhat muted colors. The chestnut-brown to orange-brown cap, straw-colored pores, hollow or chambered stalk, and firm but brittle flesh are useful field characters. The cap surface stains amber orange with NH4OH and is negative with FeSO4. The epithet castaneus is derived from the genus name for chestnut trees, Castanea, and refers to the chestnut-brown color of the cap and stalk. Cap: 3–10 cm wide, convex to broadly convex, becoming nearly plane, sometimes slightly depressed, margin often split and flaring in age; surface velvety to nearly glabrous, dry, yellow brown to orange brown or reddish brown; flesh brittle, white, not staining when cut or bruised; odor not distinctive or faintly pungent; taste not distinctive. Pores and tubes: whitish to buff or yellowish, unchanging when bruised, depressed at the stalk to nearly free at maturity; tubes 5–8 mm deep. Gyroporus castaneus (B)
210 · Boletes of Eastern North America Stalk: nearly equal or often swollen in the midportion or below, sometimes constricted at the apex and base, brittle, stuffed with a soft pith, developing several cavities or becoming hollow in age; surface dry, uneven, concolorous with the cap or slightly paler toward the apex; flesh firm, brittle, white. Habitat and season: solitary, scattered, or in groups usually in broadleaf woods, especially with oak, but also in conifer woods; late spring, summer, and fall, also winter in the southern part of its range. Distribution and frequency: throughout eastern North America; fairly common. Spore print: pale yellow. Microscopic features: spores 8–13 × 5–6 µm, ellipsoidal to ovoid, smooth, hyaline. Edibility: edible by most accounts but not particularly good. Lookalikes: Gyroporus purpurinus (p. 213) is nearly identical except for the vinaceous to burgundy colors of the cap and stalk. Austroboletus gracilis var. gracilis (p. 70) differs by having pores that become pinkish brown at maturity, a more slender and solid stalk, softer flesh, and spores that are pinkish brown and pitted. Gyroporus cyanescens
Gyroporus · 211 Gyroporus cyanescens (Bull.) Quél. = Boletus cyanescens Bull. = Gyroporus cyanescens var. cyanescens (Bull.) Quél. = Gyroporus cyanescens var. violaceotinctus Watling Common name(s): Staining Blue Bolete Overview: The term cyanescens means “becoming deep blue,” a reference to this bolete’s dramatic staining reaction. Although this species is commonly called the Staining Blue Bolete, a variety with flesh that does not stain blue when exposed has been repeatedly collected in North Carolina. Cap: 4–12 cm wide, convex to broadly convex, sometimes nearly plane, margin even, incurved when young; surface dry, covered with matted hairs or floccose scales, buff or straw yellow to pale olive, tan or yellowish, sometimes with darker streaks or an olive tinge, staining greenish blue to dark blue when bruised; flesh brittle, whitish to pale yellow, staining greenish blue to dark blue when exposed; odor and taste not distinctive. Pores and tubes: white to yellowish, yellowish green or tan, staining greenish blue to dark blue when bruised; tubes 5–10 mm deep. Stalk: nearly equal or swollen in the middle or below, brittle, stuffed with a soft pith, becoming hollow or chambered at maturity; surface dry, covered with matted hairs or scales when young, becoming smoother in age, concolorous with the cap or paler, staining greenish blue to dark blue when bruised or handled; flesh concolorous with and staining like the cap flesh. Habitat and season: solitary, scattered, or in groups in broadleaf forests and mixed woods, especially under birch and poplar, also along roadcuts; summer and fall. Distribution and frequency: widely distributed throughout eastern North America; fairly common. Spore print: pale yellow. Microscopic features: spores 8–10 × 5–6 µm, ellipsoidal, smooth, hyaline. Edibility: edible. Lookalikes: Gyroporus umbrinisquamosus Murrill (not illustrated), known only from Georgia and Florida west to Texas, is similar but has white flesh that does not change color when exposed. Gyroporus phaeocyanescens (p. 212) has a fulvous to yellow-brown cap, flesh that stains indigo blue and eventually fades to creamy buff when exposed, yellow pores that do not stain blue, and larger spores, 9–15 × 5–7 µm.
212 · Boletes of Eastern North America Gyroporus phaeocyanescens Singer & M. H. Ivory Common name(s): none. Overview: The term phaeocyanescens means “dark blue,” a reference to the indigo-blue staining reaction of this bolete’s exposed flesh. This species is typically coated with sand. The exposed flesh of water-logged specimens may not exhibit the blue staining reaction. The cap surface stains amber to orange brown with KOH and reddish brown with NH4OH and is negative with FeSO4. The flesh stains bright yellow with KOH, yellow with NH4OH, and pale yellow with FeSO4. Cap: 4–12 cm wide, convex, becoming broadly convex to nearly plane in age, margin even, incurved when young; surface dry, coated with a thick, matted covering of hairs at first, becoming appressed- fibrillose to fibrillose-scaly as the bolete matures, fulvous to yellow brown or grayish brown; flesh whitish, with a dark-brown zone beneath the cuticle, staining indigo blue when exposed, sometimes erratically, eventually fading to creamy buff; odor and taste not distinctive. Pores and tubes: whitish when young, becoming pale yellow and darkening somewhat at maturity, depressed or free near the stalk in age, not staining when bruised; tubes 5–15 mm deep. Stalk: enlarged downward or sometimes nearly equal, solid at first, becoming hollow and brittle at maturity; surface dry, coated with tiny fibrils, buff to Gyroporus phaeocyanescens
Gyroporus · 213 pale straw yellow, darkening with age or handling, especially near the base; flesh concolorous with and staining like the cap flesh. Habitat and season: scattered or in groups under oaks; summer and fall. Distribution and frequency: Georgia south to Florida, west to Texas, distribution limits yet to be established; uncommon. Spore print: pale yellow. Microscopic features: spores 9–15 × 5–7 µm, ellipsoid, smooth, pale yellow. Edibility: unknown. Lookalikes: Gyroporus cyanescens (p. 211) has a paler-colored cap and stains greenish blue to dark blue on all parts. Gyroporus umbrinisquamosus Murrill (not illustrated), known only from Georgia and Florida west to Texas, has a yellow-ocher cap with conspicuous yellow-brown fibrillose scales; white, unchanging, mild-tasting flesh; white to pale yellowish pores; and a stalk that is strongly enlarged downward with pinkish tints on the upper part and pale yellow brown below. It is associated with oaks. Gyroporus purpurinus Singer ex Davoodian & Halling = Boletus castaneus f. purpurinus Snell Common name(s): Red Gyroporus Overview: The term purpurinus means “purplish red,” a reference to this beautiful bolete’s cap and stalk color. Gyroporus purpurinus
214 · Boletes of Eastern North America Cap: 2–8 cm wide, convex, becoming broadly convex to plane, margin even, often split in age; surface dry, somewhat velvety, sometimes finely cracked and slightly scaly in age, purplish red to burgundy, paler and sometimes yellowish at the margin, fading from the margin toward the disc in age; flesh white, unchanging when cut or bruised; odor and taste not distinctive. Pores and tubes: whitish to buff at first, becoming yellowish in age, typically depressed at the stalk at maturity; tubes 5–8 mm deep. Stalk: equal or enlarged downward, brittle, hollow in age; surface dry, scurfy to somewhat velvety, purplish red to burgundy overall or sometimes whitish on the upper portion; flesh concolorous with the cap flesh. Habitat and season: scattered or in groups in mixed woods including hickory, oak, magnolia, and pine; summer and fall. Distribution and frequency: New England south to Florida, west to Minnesota; infrequent to rare. Spore print: yellow. Microscopic features: spores 8–11 × 5–7 µm, ovoid to ellipsoid, smooth, yellowish. Edibility: edible but too rare to be gathered as food. Lookalikes: Gyroporus castaneus (p. 209) is nearly identical except for the yellow-brown to orange-brown or reddish-brown colors of the cap and stalk. Austroboletus gracilis var. gracilis (p. 70) is similar, but its pores become pinkish brown at maturity; it has a pinkish-brown spore print, a solid stalk, and pitted spores. Some species in the genus Tylopilus are also similar, but they have solid stalks and pinkish-brown to reddish-brown spore prints. Gyroporus subalbellus
Harrya · 215 Gyroporus subalbellus Murrill = Suillus subalbellus (Murrill) Sacc. & Trotter Common name(s): none. Overview: The term subalbellus means “somewhat whitish,” referring to this rather pale bolete’s overall colors. The variably colored cap, chambered to hollow stalk, whitish to pale-yellow pores, lack of blue staining reaction, and distribution along the Coastal Plain are some of its distinctive identification features. Cap: 2.5–12 cm wide, convex, becoming nearly plane in age, often shallowly depressed at maturity, margin even; surface dry, nearly glabrous, color varying from apricot buff to pinkish buff or pinkish cinnamon to orange cinnamon, sometimes pale yellow to whitish, darkening to brownish in age or when handled; flesh white, unchanging when exposed; odor and taste not distinctive. Pores and tubes: whitish at first, becoming pale yellow and then dull yellow in age, unchanging or slowly staining pinkish cinnamon when bruised or in age, sometimes deeply depressed at the stalk; tubes 3–8 mm deep. Stalk: typically enlarged downward to a swollen or sometimes tapered base, hollow or chambered and brittle at maturity; surface dry, smooth, whitish at first, soon flushed pinkish to salmon orange, especially toward the base, frequently stained cinnamon to brownish or olivaceous; flesh concolorous with the cap flesh. Habitat and season: scattered or in groups in oak and pine woods; summer and fall. Distribution and frequency: along the Atlantic Seaboard from Cape Cod, Massachusetts, south to Florida, west to Texas; occasional to fairly common. Spore print: yellowish buff. Microscopic features: spores 8–14 × 4–6 µm, ellipsoid to ovoid, smooth, hyaline. Edibility: edible, mild tasting and with a firm texture but often covered with sand. Lookalikes: Tylopilus peralbidus (p. 386) is similarly colored but has bitter-tasting flesh and a pinkish-brown spore print. Genus Har rya Halling, Nuhn & Osmundson The genus Harrya was erected in 2012 to accommodate species formerly classified in several genera, including Boletus, Leccinum, Suillus, and Tylopilus. The name Harrya honors American mycologist Harry D. Thiers (1919–2000). It is a small genus with only two species known worldwide to date. Harrya chromapes is the only species reported to occur in eastern North America.
Harrya chromapes (A) Harrya chromapes (B)
Heimioporus · 217 Harrya chromapes (Frost) Halling, Nuhn, Osmundson & Manfr. Binder = Boletus chromapes Frost = Leccinum chromapes (Frost) Singer = Tylopilus chromapes (Frost) A. H. Sm. & Thiers Common name(s): Chrome-footed Bolete, Yellowfoot Bolete Overview: The term chromapes means “chrome-yellow foot.” This pretty bolete is easily recognized by its pinkish cap, pink to reddish dotted stalk, and the bright-yellow stalk base. Cap: 3–15 cm wide, convex, becoming broadly convex to nearly plane in age, sometimes slightly depressed at maturity; surface dry or slightly viscid when moist, pink to rose colored or pale grayish when young, fading to pinkish tan to dingy brown as it ages; flesh white, not staining when cut or bruised; odor not distinctive; taste not distinctive or slightly lemony. Pores and tubes: white when young, becoming pinkish to dingy pinkish tan in age, unchanging when bruised; tubes 8–14 mm deep, concolorous with the pores or paler. Stalk: nearly equal or tapered in either direction, often crooked at the base, solid; surface dry, white to pinkish, covered with pink to reddish or sometimes whitish scabers when young, with a bright chrome-yellow base; flesh white, becoming chrome yellow at the base. Habitat and season: solitary or in small groups in broadleaf and conifer woods; summer and fall. Distribution and frequency: eastern Canada south to Georgia, west to Minnesota and Texas; fairly common. Spore print: pinkish brown to reddish brown. Microscopic features: spores 11–17 × 4–5.5 µm, nearly oblong to narrowly oval, smooth, hyaline to pale brown. Edibility: edible. Lookalikes: none. Genus Heimioporus E. Horak The genus Heimioporus was erected in 2004 to accommodate species formerly classified in several genera, including Boletellus, Frostiella, and Heimiella. It was named in honor of the late French botanist and mycologist Roger Heim (1900– 1979). It is a small genus of mostly tropical and subtropical species reported from Asia, Australia, Belize, Costa Rica, Mexico, and the United States (one species). Their caps may be viscid or dry. They have dry stalks with white basal mycelium. Their spore-print color is olive brown.
Heimioporus betula (A) Heimioporus betula (B)
Heimioporus · 219 Heimioporus betula (Schwein.) E. Horak = Austroboletus betula (Schweinitz) E. Horak = Frostiella betula (Schwein.) Murrill = Heimiella betula (Schwein.) Watling Common name(s): Shaggy-stalked Bolete Overview: This long-legged bolete is one of the most distinctive and beautiful of our eastern boletes. With its disproportionately small, brightly colored, smooth cap atop a long, slender, shaggy stalk, it is unlikely to be confused with any other bolete. The name betula refers to the genus name for birch trees, Betula, many of which have shaggy bark. Cap: 3–9 cm wide, somewhat rounded to convex, margin narrow and sterile; surface smooth, glabrous, viscid when moist to somewhat tacky and shiny; bright to dark red, orange, or a blend of red and orange or orange and yellow, margin often yellow; flesh soft, pale yellow, at times tinged orange beneath the cap surface, unchanging when exposed; odor not distinctive; taste lemony or sour/acidic. Pores and tubes: bright to pale yellow or greenish yellow, usually not staining when bruised but sometimes bluing, depressed at the stalk; tubes 1–1.5 cm deep. Stalk: thin, slender, often curved near the base, solid and very firm; surface dry, coarsely reticulate-shaggy, yellow at first, becoming reddish to yellow, with a massive pad of cottony white mycelium at the base; reticulation yellow or sometimes reddish, raised; flesh concolorous with the cap flesh or at times tinged pinkish. Habitat and season: solitary or scattered in mixed broadleaf and pine woods, also in moist riparian habitats with hemlock, rhododendron, and birch; summer and fall. Distribution and frequency: Pennsylvania south to Georgia, west to Michigan; occasional to fairly common, especially in the central Appalachians. Spore print: olive brown. Microscopic features: spores 15–19 × 6–10 µm, narrowly ellipsoidal, ornamented with a loose reticulum and scattered minute pits, typically with a distinct apical pore, pale brown. Edibility: edible and considered by some to be very good but only mediocre according to others. Although the cap flesh is soft and acidic and not enjoyed by all, the stalks cook up crisp and tart and pair well with fish dishes and vegetables such as green beans and asparagus. Use young caps and all stalks—very lemony and very good. Lookalikes: Frostiella russellii (p. 207) is similar in stature but not nearly as colorful; plus, it has a dry, scaly cap. Austroboletus subflavidus (p. 71) also bears a very slight resemblance to the Shaggy-stalked Bolete but is whitish
220 · Boletes of Eastern North America in color and is known only from the Gulf Coast, the southeast Coastal Plain, and coastal areas north into New Jersey. Genus Hemileccinum Šutara The genus Hemileccinum was erected in 2008 to accommodate two European and one North American species that molecular analysis indicate do not belong in the genera Boletus, Leccinum, and Xerocomus. The name Hemileccinum means “half Leccinum.” Species in this genus have a dry, subtomentose to nearly smooth cap, yellow or white flesh that does not stain when exposed, yellow pores that do not stain when bruised, a dry stalk with pale scabers that darken only slightly in age, and an olive-brown spore print. Hemileccinum subglabripes (Peck) Halling = Boletus subglabripes Peck = Leccinum subglabripes (Peck) Singer Common name(s): none. Overview: The term subglabripes means “nearly smooth foot,” a reference to this bolete’s stalk. Macroscopically, this bolete may appear to be more closely related to the genus Boletus, but molecular studies indicate that it is not. Hemileccinum subglabripes
Hortiboletus · 221 Cap: 4.5–10 cm wide, convex to broadly convex or nearly plane in age, sometimes broadly umbonate, margin even; surface smooth to slightly wrinkled, chestnut brown, ocher, cinnamon, or reddish brown to bay brown; flesh pale yellow to whitish, rarely staining slightly blue when cut or bruised; odor not distinctive; taste mild to slightly acidic. Pores and tubes: bright yellow to yellow when fresh, duller or slightly greenish yellow in age, not staining when bruised; tubes 5–16 mm deep. Stalk: nearly equal, solid, sometimes rather stout; surface dry, minutely scurfy with a thin coating of tiny yellow scabers, yellow with occasional reddish or reddish-brown tinges, especially on the lower portion; flesh concolorous with the cap flesh. Habitat and season: scattered under broadleaf trees, especially birch, and occasionally under conifers; summer and fall. Distribution and frequency: eastern Canada south to Florida, west to Minnesota and Texas; fairly common. Spore print: olive brown. Microscopic features: spores 11–17(21) × 3–5(7) µm, narrowly fusoid, smooth, pale brown. Edibility: edible, flavor with a hint of lemon and very good. Lookalikes: Xerocomus hortonii (p. 421) is nearly identical, but it has a conspicuously pitted cap, and its stalk is typically glabrous or sometimes pruinose. It occasionally has delicate reticulation at the apex. Genus Hortibolet us Simonini, Vizzini & Gelardi The genus Hortiboletus was erected in 2015 to accommodate a single species formerly classified in the genus Xerocomellus. Since then three other species have been added worldwide to this genus. The name Hortiboletus is derived from the Latin word hortus, “garden,” and means “bolete of the gardens.” This genus differs from Xerocomellus by having reddish flesh in the stalk base, smooth spores that are never striate or truncate, and an average spore-quotient value (spore length divided by spore width) of less than 2.5. This new genus is supported by molecular analysis.
Hortiboletus campestris Boletus harrisonii
Hortiboletus · 223 Hortiboletus campestris (A. H. Sm. & Thiers) Biketova & Wasser = Boletus campestris A. H. Sm. & Thiers Common name(s): none. Overview: This is one of a confusing group of smallish, red-capped boletes. The key identification features include a red cap that becomes conspicuously cracked in age, yellow flesh that stains greenish blue when exposed, yellow pores that quickly bruise blue, and a yellow stalk that is pruinose to punctate with dull reddish-orange dots and points. The term campestris means “growing in fields,” where this bolete frequently occurs. Cap: 2–5 cm wide, convex, becoming broadly convex, margin even; surface dry, somewhat velvety, usually becoming conspicuously cracked, especially toward the margin in age, rose red when young, becoming pinkish red with a hint of yellow showing in the fissures when mature; flesh pale yellow to yellow, staining greenish blue when exposed; odor and taste not distinctive. Pores and tubes: yellow at first, becoming greenish yellow to olive yellow at maturity, staining greenish blue when bruised, typically depressed at the stalk in age; pores circular to angular, one to two per millimeter; tubes 4–8 mm deep. Stalk: nearly equal, solid; surface dry, pale yellow near the apex, deeper yellow downward, pruinose to punctate with dull reddish-orange dots and points, especially toward the base, basal mycelium yellowish; flesh bright yellow throughout, staining greenish blue. Habitat and season: scattered or in groups on lawns and grassy places in parks, open woodlands, and roadsides; summer and fall. Distribution and frequency: widely distributed throughout eastern North America; fairly common. Spore print: olive brown. Microscopic features: spores 11–15 × 4.5–7 µm, ellipsoidal to subfusoid, smooth, yellow ocher. Edibility: reported to be edible. Lookalikes: Hortiboletus rubellus (p. 225) has a stalk with dull reddish-orange punctae from the base up to a yellow apex, stalk flesh that is yellow on the upper portion and reddish orange in the base, and smaller spores that measure 10–13 × 4–5 µm. Boletus harrisonii A. H. Sm. & Thiers (see photo, p. 222), reported from Illinois, Michigan, Minnesota, and North Carolina, is very similar, but its stalk lacks the reddish-orange dots and points. It grows under broadleaf trees, especially oak, but also occurs with spruce. Microscopically, it differs from all similar species by having a cap cuticle whose last three to four cells are short and inflated and whose end cell is cystidioid to subglobose. Boletus subfraternus (p. 159) lacks conspicuous cracks on the surface of mature caps and has large, irregular to angular pores that become elongated and radially arranged to somewhat gill-like near the stalk.
Hortiboletus rubellus (A) Hortiboletus rubellus (B)
Hortiboletus · 225 Hortiboletus rubellus (Krombh.) Simonini, Vizzini & Gelardi = Boletus fraternus Peck = Boletus rubellus Krombholz = Xerocomellus rubellus (Krombh.) Šutara = Xerocomus rubellus (Krombholz) Quél. Common name(s): none. Overview: The term rubellus means “reddish,” a reference to the colors of this bolete’s cap and stalk. There was formerly much confusion about the identification of this beautiful bolete and in separating it from very similar species. Thanks to molecular analysis, much of the confusion has been eliminated. Cap: 2–8 cm wide, convex, becoming nearly plane in age, margin even; surface dry, somewhat velvety, often becoming finely cracked in age, dark red, fading in age to brick red or olivaceous brown; flesh pale yellow, slowly staining bluish green on exposure; odor and taste not distinctive. Pores and tubes: yellow, staining bluish green when bruised, typically depressed at the stalk when mature; tubes 6–10 mm deep. Stalk: nearly equal, enlarged or tapered downward, often with a narrowed base, solid; surface dry, yellow at the apex, pruinose to punctate with dull reddish-orange dots and points, darkening to brown where handled; flesh yellow on the upper portion, reddish orange below or at least near the base. Habitat and season: solitary, scattered, or in groups in grassy areas, parks, gardens, flowerbeds, and disturbed roadsides as well as along paths or in broadleaf and mixed woods, especially under oak and beech; summer and fall. Distribution and frequency: widespread throughout eastern North America; occasional to fairly common. Spore print: olive brown. Microscopic features: spores 10–13 × 4–5 µm, ellipsoidal, smooth, pale brown. Edibility: unknown. Lookalikes: Hortiboletus campestris (p. 223) is very similar, but its stalk flesh is bright yellow throughout, not reddish orange in the base, and it has somewhat larger spores that measure 11–15 × 4.5–7 µm. Its cap surface stains amber with KOH and dark green to blackish green with FeSO4. Its flesh stains orange with KOH and dull orange with FeSO4. Boletus harrisonii A. H. Sm. & Thiers (see photo, p. 222), reported from Illinois, Michigan, and Minnesota, is also very similar, but its stalk lacks reddish-orange dots and points. It grows under broadleaf trees, especially oak, but also occurs with spruce. Microscopically, it differs from all similar species by having a cap cuticle whose last three to four cells are short and inflated and whose end cell is cystidioid to subglobose. Boletus subfraternus (p. 159) has large, irregular to angular pores, and its cap does not become cracked with age.
226 · Boletes of Eastern North America Genus Imler ia Vizzini The genus Imleria was erected in 2014 to accommodate a single species, Imleria badia, which was formerly classified in several genera, including Boletus, Suillus, and Xerocomus. This genus was named in honor of Belgian mycologist Louis Imler (1900–1993). It presently consists of five species worldwide. Imleria badia (A) Imleria badia (B)
Imleria · 227 Imleria badia (Fr.) Vizzini = Boletus badius (Fr.) Fr. = Xerocomus badius (Fr.) E.-J. Gilbert Common name(s): Bay Bolete Overview: This medium-size bolete is a conifer associate and not difficult to identify. It is an excellent edible that is well worth getting to know. The term badius means “bay brown,” which is chestnut brown or reddish brown. The cap surface stains green to blue with NH4OH, blackish with KOH, and bluish green with FeSO4. Cap: 4–9 cm wide, convex to broadly convex, becoming nearly plane at maturity, sometimes depressed in the center, margin upturned in age, even; surface dry to slightly viscid, smooth or somewhat velvety, chestnut brown, reddish brown, or yellow brown, sometimes with olive tones; flesh soft, white, often staining bluish, at least near the tubes, when cut; odor and taste not distinctive. Pores and tubes: pale yellow to greenish yellow, quickly staining greenish blue to grayish blue when bruised; tubes 8–15 mm deep. Stalk: nearly equal or enlarged downward, solid; surface dry, smooth to somewhat pruinose, concolorous with the cap, with a white basal mycelium; flesh concolorous with and staining like the cap flesh. Habitat and season: solitary or scattered under pines or other conifers, sometimes on decaying conifer stumps or in hardwoods; summer and fall. Distribution and frequency: eastern Canada south to North Carolina, west to Minnesota; fairly common. Spore print: olive brown. Microscopic features: spores 10–14 × 4–5 µm, ellipsoidal to fusiform, smooth, yellow. Edibility: Edible and very good. Tubes from older specimens can be removed, dried, and powdered for seasoning. The flesh is not often damaged by insects. Lookalikes: Xanthoconium affine (p. 409) has a dark-brown to chestnut-brown or ocher-brown cap and white pores that become yellowish to dingy yellow brown at maturity and stain dull yellow to brownish, not blue, when bruised. Aureoboletus projectellus (p. 64) has similar colors but is typically more robust and has a coarsely reticulate stalk. Boletus glabellus Peck (not illustrated), reported from New England west to Ohio and Michigan, has a pale-brown to yellow-brown dry cap, sometimes with reddish tinges, that often becomes finely cracked in age. It has whitish flesh that stains blue when exposed, pale greenish-yellow pores that become ochraceous to brownish at maturity and stain blue when bruised, and a dullwhite to yellowish stalk with reddish to purple-red tinges, especially toward the base. Its stalk flesh is deep yellow toward the base and pale yellow
228 · Boletes of Eastern North America above the base and stains blue when exposed. Its spores measure 9–13 × 3–5 µm, and it grows in grassy areas or in woods with oaks. Similarly colored species in the genus Tylopilus have white or pinkish-brown spores that do not stain blue when bruised and produce a pinkish-brown spore print. Genus L anmaoa G. Wu & Zhu L. Yang The genus Lanmaoa was erected in 2015 to accommodate species formerly classified in several genera, including Boletus, Leccinum, and Suillus. Lanmaoa was named in honor of Mr. Lan Mao (1397–1476), a Chinese botanist from the Ming dynasty who first used the Chinese term niuganjun for boletes in the Chinese literature. The species included in this genus do not share very many macroscopic characteristics. However, DNA analysis clearly demonstrates that they are closely related. The genus Lanmaoa includes two species from China, one from Costa Rica, and four from eastern North America, including Lanmaoa roseocrispans, a species only recently described from Florida. They are mediumto large-size terrestrial boletes with dry caps and solid stalks. Their flesh is pale yellow to bright yellow and stains blue in most species when exposed. Pores are typically yellow, bruising blue and sometimes brown. One non–North American species has dull-orange to orange-red pores. Lanmaoa borealis
Lanmaoa · 229 Lanmaoa borealis (A. H. Sm. & Thiers) A. E. Bessette, M. E. Nuhn & R. E. Halling, comb. et stat. nov. MycoBank: MB811208 = Boletus bicolor var. borealis A. H. Sm. & Thiers, Boletes of Michigan (Ann Arbor): 277. 1971. Common name (s): none. Overview: We have elevated this variety to species rank based on the results of molecular analysis obtained by Gang Wu and his colleagues (2014). The key identification features include a red cap, yellow flesh that slowly stains blue at the stalk apex, orange-red to red pores that stain greenish blue, and a red stalk that may be reticulate at the apex. Cap: 2–12 cm wide, obtuse to convex at first; surface dry, glabrous or nearly so, dark red to bright apple red, becoming brick red to dull rusty rose in age; flesh yellow to pale yellow, slowly bluing at the stalk apex when exposed; odor and taste not distinctive. Pores and tubes: orange red to red, staining greenish blue when bruised, becoming dull brownish red and sometimes depressed near the stalk in age; tubes 6–10 mm deep. Stalk: tapered downward or nearly equal, solid; surface dry, nearly glabrous, colored like the cap, lacking reticulation or reticulate only at the apex; flesh yellow to pale yellow, slowly bluing at the apex, vinaceous brown at the base. Habitat and season: solitary, scattered, or in groups under broadleaf trees or in mixed woods; summer and fall. Distribution and frequency: recorded from Michigan east to New England, distribution limits yet to be determined; uncommon. Spore print: olive brown. Microscopic features: spores 11–15 × 4–5 µm, subfusoid, smooth, pale yellow. Edibility: poisonous, causing gastrointestinal distress. Lookalikes: Species in the Baorangia bicolor complex (p. 74) are similar, but they have yellow pores.