Trial field key to TOOTHED FUNGI in the Pacific Northwest
Prepared for the Pacific Northwest Key Council
By Dorothy Henderson August 1981
Copyright  1981, 2007, 2017, 2019 Pacific Northwest Key Council
minor revision, species keys, and species descriptions by Ian Gibson 2007
taxonomic updates Ian Gibson 2017 and 2019

TABLE OF CONTENTS

Introduction to Toothed Fungi	1
Key to genera of Toothed Fungi	5
Key to Bankera	6
Key to Hericium	6
Key to Phellodon	8
Key to Hydnum	10
References	11
Index	12

INTRODUCTION TO TOOTHED FUNGI

These notes are designed to be helpful in identifying seven genera of stipitate (stemmed) toothed fungi as they occur in the Pacific Northwest, with comments on the most commonly found species in each genus. Hericium is usually included with this group, although it does not have a true stem. Dr. Kenneth Harrison, the North American expert, says of the group, “The remarkable longevity of individual sporophores of many species and the changes in appearance that occur during the long period of their development have confused all workers studying this group.” Amen!

	The fruitbody can be fleshy (firm or fragile), leathery or woody, (gelatinous only for Pseudohydnum gelatinosum). Spores can be brown or white, rough or smooth – but all are borne on projecting or downward hanging spines or teeth. Often a pleasant fragrance remains after drying. 

	Six genera have white spores: Auriscalpium, Hericium, Hydnum, Phellodon, Pseudohydnum, and Bankera. These genera have only a few species in the Pacific Northwest and their species descriptions are given here. Following the molecular findings of Niskanen et al.(2018), at least six species of Hydnum have been found in the Pacific Northwest. See the note below under Hydnum later in this Introduction.
 
	Two genera have brown spores: Sarcodon and Hydnellum. They are considered in detail in separate documents, but the borderline between the two has been obscured by the molecular findings of Larssen et al.(2019) which appear to include most species known as Sarcodon in the same clade as Hydnellum. See the note below under Sarcodon later in this Introduction.

Some confusion could result from the fact that the Sarcodon species were formerly called Hydnum and the Hydnum species formerly called Dentinum. The older names are used in the excellent field guide Mushrooms Demystified by David Arora.

	Traditionally Hydnum, Hericium, Phellodon, Bankera, Sarcodon, and Hydnellum are studied together, and they have certain similarities that once placed them all in the family Hydnaceae. All but Hydnum have been moved, Hericium to Hericiaceae, and the rest  to Bankeraceae. Baird et al.(2013) synonymized Bankera with Phellodon. The process of determining genetic relationships by modern molecular techniques is not yet complete. 

Auriscalpium vulgare is included here because of its obvious teeth. Pseudohydnum gelatinosum, the so-called toothed jelly, in unrelated and quite different, but is very common and does have teeth on the underside of its cap. (This would presumably be a case of convergent evolution: there are only so many ways that the spore-bearing area can increase its surface.) The term “stipitate” excludes certain polypores that have teeth on the underside, notably Echinodontium tinctorium, and some fruitbodies of others like Trichaptum abietinum may show tooth-like patterns on the underside. An array of polypores and crust fungi that grow mostly flat on wood show a toothed surface (Hyphodontia for instance), but these are not considered further here as their identification would normally require microscopic examination.

Auriscalpium  –  Fruitbody small (2-7 cm tall), tough, brown hairy cap and lateral stipe, growing only on decaying buried conifers cones – in most of northern U.S. on pine but in this area on Douglas-fir. A single species, Auriscalpium vulgare.

Hericium  –  Fruitbody is a framework of branches with projecting or hanging spines of various sizes, loose or compact. All grow on wood and are edible. Four species occur in the PNW.

	H. erinaceus  –  solid mass with spines that can be 6 cm long, white, yellowing in age; grows only on deciduous wood, oak along Pacific Coast, in this area on maple; common name Bear’s Head.

	H. coralloides  –  branches intricate and fused, spines short, pure white; grows only on deciduous wood, usually poplar.

	H. abietis  –  variable in size but can be massive when mature, up to 75 x 25 cm, compact or openly branched, white to cream when young, yellowish gray or darker in age; growing on conifers; several forms include forma brevispineum with short spines (1-3 mm) on flexuous branches and forma weirii, very compact with short branches hidden by spines (20-25 mm).

	H. americanum  –  similar to H. abietis but growing on hardwoods, spore size different.

Hydnum  –  Fruit body fleshy, brittle; stipe central, eccentric or lateral; in moss or duff under mixed conifers. Two species, both edible have long been recognized in the Pacific Northwest. Niskanen et al.(2018) described more species, so that there is evidence of at least six species. We include in the Hydnum repandum group Hydnum neorepandum, Hydnum olympicum, and Hydnum melleopallidum (with fruitbodies that have predominantly decurrent teeth and predominantly pale pinkish orange to pale brownish caps, and may be larger and more robust). We include in the Hydnum umbilicatum group Hydnum oregonensis, Hydnum cf. umbilicatum, and Hydnum melitosarx (with fruitbodies that have predominantly non-decurrent teeth, and may have predominantly ochraceous to orange brown caps).

	H. repandum [from original key] –  cap 3-10 cm broad, convex to slightly depressed, yellowish white to pale orange becoming darker when bruised; stipe short, thick.

	H. umbilicatum [from original key] –  smaller, abruptly umbilicate, deeper orangey color; stipe thin and long.

Phellodon  –  Fruit body small to medium size; thin cap, often zoned; flesh tough, fibrous; spines pale gray to buff; singly or in fused masses under mixed conifers. Three species, possibly more.

	Phellodon tomentosus  –  some shade of brown, strongly zoned, margin whitish; up to 6 cm tall, 5.5 cm broad; fragrant.

	Phellodon melaleucus and P. atratus  –   very similar with dark gray blue to black coloration; the former is velvety, more delicate, with a thin radicating stipe; the latter has whitish margin, is more robust, very abundant in second growth conifer.

Bankera  –  Fruit body large (8-15 cm), some shade of brown with brittle flesh and whitish spines. (According to K. Harrison this genus bears the same relationship to Phellodon in white-spored group as Sarcodon does to Hydnellum in brown-spored group.) [Both species have proposed current names in Phellodon.]

	Bankera fuligineoalba  –  large dark brown cap with wavy lighter margin; short stout mushroom often covered with duff. (One collection reported from Oregon.)

	Bankera violascens  –  grayish brown cap becoming cracked and scaly with split, incurved margin.

Sarcodon  –  The cap is fleshy, sometimes fragile, like a conventional gilled mushroom. More than a dozen species occur in the PNW; collections often do not fit descriptions. Among the more recognizable are:

	S. imbricatus  –   large with large medium brown upturned scales on lighter brown background, often sunken disk cap, preferred Sitka spruce forest habitat, and dyeing wool. grayish beige

	S. squamosus –  separated from S. imbricatus by vinaceous to brown cap, often dark vinaceous brown to purplish black, slightly smaller cap scales, lesser likelihood of a deeply sunken disk, preferred pine habitat, and dying wool bluish green not grayish beige. Older guides include it as part of S. imbricatus.

	S. scabrosus  –   with smaller flattened scales; long (1 cm) spines interspersed with short ones; taste bitter, stem base olive-black.

	S. fuscoindicus  –   gray-lavender cap and stipe, with firm purple flesh.

	S. stereosarcinon  –   large, dark reddish brown, zoned; drying hard and woody – like a cross with Hydnellum.

	S. calvatus  –   very large (15-28 cm) cream buff cap; variety odoratum has strong sweet fragrance.

	S. atroviridis  –   grayish tan with enlarged stem base; entire mushroom olive green when dry.
	
	Note that if we follow Larsson et al.(2019), S. fuscoindicus is Hydnellum fuscoindicum, Sarcodon scabrosus is Hydnellum scabrosum, S. imbricatus and S. squamosus remain in Sarcodon, S. atroviridis may have a different status, and both S. stereosarcinon and S. calvatus are undetermined [but on spore size criteria are more likely to be in Hydnellum].

Hydnellum  –  The cap is tough, fibrous, with indeterminate growth – stopping then resuming with weather changes, often surrounding twigs, leaves, cones. Cap and/or stipe can be fused. K. Harrison said that it is difficult to draw a sharp line between Sardodon and Hydnellum, two genera under all conditions of growth. 8 or 10 species.

	H. caeruleum  –  white cap margin tinted blue when actively growing; cap flesh blue-zoned, stem flesh reddish.

	H. aurantiacum  –  at first pure white, turbinate and tomentose, changing to orange to rusty brown to brownish black, plane, corrugated and glabrous.

	H. peckii  –  whitish with dull red cast, finally brown, exuding red droplets in wet weather, very fragrant (similar to and confused with H. diabolus).

	H. suaveolens  –  squat, white changing to gray-brown; very pleasant fragrance while growing and on drying.

	H. regium  –  large complex deep violet black cap of numerous rosettes.

	H. scrobiculatum  –  brownish caps, usually fused, with rough, deeply pitted surface; stipe base bulbous, thickened.

	See also Sarcodon above for species traditionally included in Sarcodon which may be Hydnellum according to molecular research.

KEY TO GENERA OF TOOTHED FUNGI

1a	Fruitbody whitish and jelly-like, stem off-center	Pseudohydnum gelatinosum

CAP 2-6 cm wide, projecting 2-4 cm, 0.5-1.0 cm thick, tongue-shaped to fan-shaped or bracket-like, flabby-rubbery-gelatinous, translucent white, less commonly gray to gray-brown, upper surface rough. TEETH up to 3(5) mm long, crowded, pallid. STEM colored as cap with similar consistency, up to 6 cm, usually lateral, continuous with cap. FRUITING clustered to single, on conifer wood or humus under conifers. SPORES 5-6 x 4.5-5.5 um, round to nearly round, smooth, inamyloid, (Breitenbach & Kränzlin), 5-8.5 um in diameter, round or nearly round, (Arora).

1b	Fruitbody not whitish and jelly-like, stem central or off-center	2

2a	Fruitbody grows on wood or cones	3

2b	Fruitbody grows on soil or duff	4

3a	Fruitbody has framework of branches with spines (no true cap)	Hericium

3b	Fruitbody grows on cones (usually Douglas Fir in PNW)	Auriscalpium vulgare

CAP 1-2(4) cm wide, kidney-shaped to almost circular, brown; covered with dense fibrils, margin fringed. FLESH thin, tough, leathery, white. TEETH 1-3 mm long, crowded, white to flesh-colored or brown. STEM 2-10 cm long and 0.5-3 mm wide, usually lateral, attached at a notch in cap, pliable, rusty-brown to dark brown, densely hairy, especially in lower part. FRUITING single or in groups of two or three on rotting, often buried conifer cones, typically Douglas-fir or Ponderosa Pine. SPORES 4.5-6 x 3-5.3 um, round or nearly round, smooth or minutely spiny, amyloid.

4a	(2b)  Spores white 	5

4b	Spores brown	7

5a	Flesh tough, fibrous, thin, growth indeterminate (stopping then resuming with weather changes), caps often fused	Phellodon

5b	Flesh firm to brittle, thick, growth determinate, caps single	6

6a	Cap color pale shades of cream or orange	Hydnum (formerly Dentinum)

6b	Cap color shades of brown or gray (infrequently encountered)	Bankera

7a	(4b) Flesh firm to fragile, growth determinate, medium to large	Sarcodon (formerly Hydnum)
	(See Key to Sarcodon)

7b	Flesh tough, fibrous, growth indeterminate, often fused, small to medium	Hydnellum
	(See Notes on Hydnellum)

KEY TO BANKERA

101a	Cap not becoming scaly, growing under pine, often with pine needles adhering tightly to soft surface of cap, (not reacting to KOH when dried)	Bankera fuligineoalba

CAP 5-13 cm, convex becoming flat to depressed or when old umbilicate, margin incurved, lobed, wavy; dull dark brown progressing through light brown to fawn and to vinaceous fawn to the margin (also described as becoming red-brown to yellow-brown), darker when wet; unpolished, when dry with adherent debris partly due to binding by surface hyphae, rarely diffracted scaly. FLESH brittle to slightly fibrous, white or tan to vinaceous buff, not zoned, in stem fibrous, pale vinaceous-buff, fawn or tan. TEETH 3-5(8) mm long, up to 0.5 mm wide, slightly decurrent, close, white or whitish becoming light red-brownish to gray-brownish. STEM 2-5 cm x 1-3 cm, colored as cap, lightest in color next to the teeth, unpolished, smooth, finely tomentose. ODOR when fresh not distinctive, when dried the odor distinctive (as in most species of Phellodon), intensely like Maggi seasoning. TASTE mild. FRUITING single to scattered or gregarious, usually under pine. CHEMICAL REACTIONS when dried not reacting to KOH and Melzer's reagent (Harrison 1968). MICROSTRUCTURES spores 4-5(6) x 4-5 um (Harrison 1968), 4.5-5.5 x 2.7-3.5 um excluding ornamentation (Breitenbach & Kränzlin), nearly round, coarsely echinulate (with spines), colorless, inamyloid; basidia 4-spored; no cystidia; no clamps; cap surface a cutis.

101b	Cap bald to lacerate scaly, growing under various conifers, surface not holding debris conspicuously, (turning dark olivaceous with KOH when dried)	Bankera violascens

CAP 3-13 cm, depressed, flat, or lobed and wavy; grayish brown or pale pinkish brown or pale purplish brown, dull brown to dark brown when old, whitish to pale fawn on margin; at first bald and unpolished, becoming finely tomentose or diffracted or lacerate scaly with scales small and appressed. FLESH soft, pallid to light brown or tinted faintly pinkish or lilac, not zoned; in stem apex as in cap, harder downward, browner to dark umber (or tinted pinkish or purplish) at base when old. TEETH 5-6 mm long, 0.5 mm wide, decurrent, fairly close, white to pallid, becoming pinkish buff or grayish. STEM 3-10 cm x 1-2 cm, single or sometimes the upper third branched, darker than cap, colored like cap but usually darker brown, often whitish near top and dark brown at the base when old; smooth, often becoming lacerate scaly. ODOR faintly fragrant, strongly fragrant when dried, (Harrison 1968), fragrant like maple syrup when fresh, soon disappearing after picking, (Bessette), pleasant, when dry intensely like Maggi seasoning, (Breitenbach & Kränzlin). TASTE mild. FRUITING single, gregarious, to cespitose under conifers. CHEMICAL REACTIONS cap and flesh instantly dark olive-green with KOH (Bessette), KOH turns dried flesh pale olivaceous, (Harrison). MICROSTRUCTURES spores 4-5.5 x 4-5 um, nearly round, coarsely echinulate, inamyloid; cystidia not seen; no clamps.

KEY TO HERICIUM

Arora (1986) discusses nomenclatural intricacies in this genus. Hericium erinaceus (lion’s mane Hericium) is easily distinguishable because it is unbranched, usually with long spines. There are three other recognizable species in the Pacific Northwest, one white to salmon-buff when fresh, with clustered spines, and growth on conifers (conifer coral Hericium), a similar one that prefers hardwoods, and has slightly longer spores, (hardwood coral Hericium), and one with spines arranged in rows along the branches like teeth on a comb, growing on hardwoods (comb Hericium). The approach of Ginns (1993) is used here, in which the comb Hericium (H. ramosum as referred to by Arora) is called H. coralloides (Scop.: Fr.) Pers. and the hardwood coral Hericium (H. coralloides as referred to by Arora) is called H. americanum Ginns. All four species have mild ODOR and TASTE. There is a negative reaction in each case when KOH is applied to the tissues, but they give an amyloid reaction to Melzer’s reagent.

KEY TO HERICIUM cont.

201a	Fruitbody unbranched, consisting of a tough piece of tissue from which spines 2-4(7) cm long hang down, growing on hardwoods	Hericium erinaceus

CAP 8-40 cm across, an unbranched mass of long, closely-packed, parallel spines hanging from a tough piece of tissue, the spines white, discoloring yellowish to brownish when old. TEETH (1)2-5(7) cm long, soft when fresh. FRUITING on wounds of living hardwoods or cut ends of recently felled hardwood logs. SPORES 5-6.5 x 4-5.5 um, nearly round, smooth to minutely punctate-roughened, amyloid. REMARKS "erinaceus" meaning “hedgehog” has the masculine ending “-us” even though Hericium is neuter, because "erinaceus" is a noun, not an adjective.

201b	Fruitbody branched, spines usually less than 2 cm long hanging down from branch tips or along the branches	202

202a	Spines arranged in rows along the branches like teeth on a comb, branching open rather than compact, growing on hardwoods	Hericium coralloides

CAP 8-35 cm across, consisting of an open framework of rather delicate, spine-laden branches arising from repeatedly branching base, the spines distributed along the branches somewhat like teeth on a comb, but also in small tufts at the branch tips, white when fresh, discoloring cream to buffy brown or yellowish tan when old. TEETH 0.3-1.0 cm long, mostly less than 0.7 cm, or up to 2.5 cm long in tufts, slender, tapering. STEM short, tough. FRUITING on hardwoods. SPORES 3.1-5 x 3-4 um, nearly round, smooth or minutely roughened, amyloid.

202b	Spines arranged in clusters, mostly at the ends of branches, growing on conifers or hardwoods	203

203a	Growing on conifers, white to salmon-tinged or yellowish-tinged when fresh, spines up to 25 mm but usually 5-10 mm, (spores 4.5-5.5 x 4.0-4.5 um)	Hericium abietis

CAP 10-75 cm across, main branches up to 3 cm thick, branching repeatedly, bearing clusters of spines on the ends of branches and from lateral nodules, white to creamy, yellowish-buff, orange-buff. TEETH up to 2.5 cm long, usually 0.5-1.0 cm long, fleshy but brittle. STEM thick, knob-like, tough. FRUITING single or sometimes several together on dead conifers. SPORES 4.5-5.5 x 4.0-4.5 um, round or nearly round, smooth or minutely roughened, amyloid. REMARKS Hericium abietis in one of its growth forms (formerly Hericium weirii) is similar to H. erinaceus which however grows on hardwoods, and in another of its growth forms brevispineum is extensively branched with very short spines (0.1-0.5 cm), resembling H. coralloides (Scop: Fr.) Pers. which however also grows on hardwoods, (Arora who refers to the latter species as H. ramosum).

203b	Growing mainly on hardwoods, white when fresh, (spores 5.5-7.0 x 4.5-6.0 um)		
		Hericium americanum

CAP up to 30 cm across, main branches stout and branching repeatedly, bearing clusters of spines on the ends of branches and from lateral nodules, white becoming cream-colored when old. TEETH 0.5-1.5 cm long, stout, tapering to a slender tip, fleshy, brittle to tough. STEM represented by a short pseudorhiza that soon branches, or as a tubercle with short branches. FRUITING on wood of hardwoods and conifers. SPORES 5.5-7.0 x 4.5-6.0 um round to nearly round, finely roughened to almost smooth, amyloid. REMARKS Arora says that spines grow up to 4 cm.

KEY TO PHELLODON

301a	Cap yellow brown to dark brown, strongly zoned; flesh brown	Phellodon tomentosus

CAP 1-6 cm across, often fused with other caps, flat to depressed or broadly funnel-shaped or umbilicate, white when very young, typically soon concentrically zoned by color only, yellow-brown, gray-brown, reddish brown or dark brown, the margin usually remaining white, but bruising brownish; dry, smooth to ridged, tomentose or radially fibrillose, margin felty. FLESH 1-1.5 mm thick, leathery, fibrous, brownish in cap, darker brown in stem, zoned with brownish tan outer corky layer and dark brown inner layer, duff included in base. TEETH 1-2(5) mm, crowded, slightly decurrent, white, shaded with buff when old, staining vinaceous-buff when bruised, tips paler. STEM 2-5 cm long, 2-5(8) mm wide, usually central, equal or narrowing downward, stems usually separate even if several caps fused together, colored as cap, smooth to somewhat fibrillose, arising from felty layer of brownish mycelium. ODOR mild to fragrant (like fenugreek) especially as fruitbodies dry, or like blackstrap molasses or Maggi seasoning. TASTE mild, slightly bitter, or slightly sweetish with a slight biting reaction in the throat. FRUITING scattered to cespitose under conifers. CHEMICAL REACTIONS flesh turns black in KOH when fresh but not when dried. SPORES 3-4 um in diameter, round to nearly round, finely echinulate, (Harrison), 3-4 x 2.5-3.5 um (Breitenbach & Kränzlin). REMARKS Phellodon melaleucus has flesh that turns green with KOH. Hydnellum species that are zoned have brown spore deposit and generally darker teeth or different odor.

301b	Cap blackish, purple-black, blue-black, or dark brown, not strongly zoned; flesh blackish, purple-black, blue-black, or purple-gray	302

302a	Cap blue-black to purple-black with margin often slightly paler or purpler, flesh similar in color, spines gray to dark purple-gray-brown; relatively robust; (dark granules in Melzer’s reagent in flesh but not surface layer of cap, flesh reaction in KOH deep bluish black)	Phellodon atratus

CAP 1-5 cm across but often fused with other caps, flat to depressed or irregular, sometimes bearing small caps, bluish black to black or purple-black, usually at least faintly zoned concentrically, at least near margin, uneven, appressed-fibrillose, slightly scrobiculate (with shallow pits); margin thin, often slightly paler or purpler and bruising to purple-black when handled, uneven and when old torn-fringed. FLESH in cap and stem thin (2-5 mm in cap), tough, sometimes with thin upper spongy layer; purple-black to bluish black, in stem bruising blackish brown. TEETH 1-2 mm, irregularly decurrent, close, gray to dark purplish-gray-brown or blackish brown, darker where bruised. STEM 2-5 cm long, 3-5 mm wide, frequently flattened, sometimes rooting, enlarged at ground by felty layer of spongy mycelium, sometimes branched to produce a compound fruiting body, firm to almost woody in center although occasionally juice can be squeezed out, surface dull bluish black to blackish, rough, subtomentose, becoming blackish brown when bruised. ODOR mild or faintly fragrant or smoky fungoid or fenugreek. TASTE mild. FRUITING scattered to gregarious under conifers. CHEMICAL REACTIONS Under the microscope, the reaction of the flesh in KOH is deep bluish black, and some of the dark granules in the hyphae and their color leached into solution; in Melzer’s reagent flesh appeared amyloid and the color of granules intensified; there were no granules in the thin layer of hyphae on the cap surface although it darkened somewhat in Melzer’s reagent. SPORES 4.5-5 x 4-5 um, round to nearly round, finely echinulate (spiny), with 10-15 processes visible on circumference. REMARKS Sarcodon fuscoindicus somewhat similar in color but larger and fleshy-brittle rather than tough.

302b	Cap usually dark brown with pale margin, flesh brown or purple-gray to purple-black; spines whitish to gray; relatively delicate; (dark granules in Melzer’s reagent in surface layers of cap but not in flesh, flesh reaction in KOH dark olivaceous)	Phellodon melaleucus

CAP 1-6 cm but often several caps growing together and then wider, flat or disc depressed and rough, sometimes with small caps attached, dark brown to purplish brown or purplish gray, (margin paler), bruising darker, appressed-fibrillose, appearing zoned concentrically when moist but not on drying, margin thin, wavy, irregular. FLESH thin (2-5 mm in cap), tough, faintly duplex (with upper layer soft-felty), brown or purple-gray to purple-black, in stem duplex with hard inner core and corky thin outer layer. TEETH 1-1.5 mm long, close, irregularly decurrent, whitish to dull gray, bruising brownish black. STEM 3-6 cm long, 2-6 mm wide, compound, rooting up to 10 cm but black pseudorhiza easily lost when collecting, stem sometimes branched, dark brown or purple brown or vinaceous brown. ODOR mild when fresh, when dried with the strongly fragrant odor of most Phellodon species, (Harrison), of fenugreek especially dried (Hall 1971), like Maggi seasoning when drying (Breitenbach & Kränzlin). TASTE mild to somewhat bitter. FRUITING gregarious to concrescent (growing joined) in large masses, under conifers. CHEMICAL REACTIONS Under the microscope, flesh turns dark olivaceous with KOH; in Melzer’s reagent the flesh does not appear to be amyloid and dark granules are found only in the cuticular hyphae. SPORES 4-5 um in diameter, round to nearly round, finely echinulate, in Melzer's reagent no reaction in spines or flesh, but in the surface hairs and in some of the hyphae next to the hairs a slight apparent-amyloid reaction. REMARKS Phellodon melaleucus, unless rain-soaked, is dark brown with contrasting white margin whereas Phellodon atratus is nearly black.

KEY TO HYDNUM

401a	Cap convex, flat or depressed, up to 17 cm across, stem 1-3 cm thick	Hydnum repandum group

See Note under Hydnum in the Introduction. The description here is before Niskanen et al.(2018)
CAP 2-17(25) cm, convex to flat or depressed, surface and margin often wavy; pale flesh-color to pale orange, salmon, orange-tan, pale tan, pale cinnamon, or pale reddish brown (but white to creamy in var. album), bruised areas often darker orange; smooth to felty, sometimes cracking into scales when old. FLESH white, usually turning yellow to yellow-brown or orange or orange-brown when bruised. TEETH 2-7 mm long, often decurrent, whitish or pale ochraceous, bruising orange to ochraceous. STEM 3-10 cm x (0.5)1-3(5) cm, central or off-center, equal or widening in lower part or occasionally narrowing downward, white or colored like cap but usually paler, bruising yellow-brown to dark orange-brown. ODOR mild. TASTE mild to somewhat bitter or peppery. FRUITING single, scattered, or gregarious, under hardwoods and conifers. SPORES 6.5-9 x 5.5-8 um, broadly elliptic to nearly round, smooth, (Arora), 8.0-8.7 x 6.2-7.0 um, inamyloid, (Hall 1971 for var. repandum, giving 9.0-9.8 x 7.6 um or longer for var. macrosporum nom. prov. and 6.7-7.3 x 4.7-6.7 um for var. album). REMARKS not all authors agree with the synonymy of Hydnum washingtonianum with larger spores and pink tones to the cap.

401b	Cap with central depression, up to 6.5 cm across, stem usually less than 1 cm thick 	
		Hydnum umbilicatum group

See Note under Hydnum in the Introduction. The description here is before Niskanen et al.(2018)
CAP 2-6.5 cm, convex to flat with fairly abrupt central depression (umbilicate), often with the depression continuing into the stem, surface and margin wavy; pale yellow to pale orange-yellow, becoming deep orange or reddish orange or brownish orange, slowly bruising orange; bald or slightly felted. FLESH whitish, bruising orange. TEETH up to 6 mm long, not decurrent, whitish or pale ochraceous, bruising pale orange. STEM up to 8 cm long, mostly under 1.0 cm wide, 0.45-0.7 cm wide near top, nearly central to less often off-center, may narrow slightly downward, base slightly swollen; slightly paler than cap, bruising orange. ODOR and TASTE mild. FRUITING single or gregarious, on ground in duff of coniferous forests. SPORES 9.0-10.0 x 7.0-8.6 um, nearly round, smooth, inamyloid, (Hall 1971), 7.5-9 x 6-7.5 um, nearly round, tuberculate, smooth, (Phillips), 7.5-9.5 x 6-7.5 um (Bessette). REMARKS In addition to the differences mentioned in the key lead, Hydnum repandum tends to have a lighter cap color with less red tone, more irregular outline, and more robust stature (thicker flesh and relatively shorter stem). Spores are usually smaller but there is a var. macrosporum nom. prov. with spores 9 um or longer.

REFERENCES

Arora, David.  1986   Mushrooms Demystified   Second Edition.  Ten Speed Press, Berkeley.   
Baird, Richard E.  1986a.  “Type studies of North American and other related taxa of stipitate hydnums: Genera Bankera, Hydnellum, Phellodon, Sarcodon.”  Bibliotheca Mycologica Band 103: 1-89.  
Baird, Richard E.  1986b.  “Study of the stipitate hydnums from the Southern Appalachian Mountains – Genera: Bankera, Hydnellum, Phellodon, Sarcodon.” Bibliotheca Mycologica Band 104: 1-156. 
Baird, R., L.E. Wallace, G. Baker et al. 2003. “Stipitate hydnoid fungi of the temperate southeastern United States”. Fungal Diversity 62: 41.
Banker, H.J.  1913.  “Type Studies in the Hydnaceae - V. The genus Hydnellum.”  Mycologia 5: 194-205.
Bessette, Alan E., Bessette, Arleen R., Fischer, David W.  1997.  Mushrooms of Northeastern North America.  Syracuse University Press. 
Breitenbach, J., Kränzlin, F.  1986.  Fungi of Switzerland  Volume 2 Non-gilled Fungi.  Edition Mykologia Lucerne. 
Coker, William Chambers, and Alma Holland Beers.  1951. The Stipitate Hydnums of the Eastern United States.  Chapel Hill. The University of North Carolina Press.
Hall, D., D.E. Stuntz.  1971.  “Pileate Hydnaceae of the Puget Sound Area. I. White-spored genera: Auriscalpium, Hericium, Dentinum, and Phellodon.”  Mycologia 63(6): 1009-1127.
Hall, D., D.E. Stuntz.  1972.  “Pileate Hydnaceae of the Puget Sound Area. II. Brown-spored genera: Hydnum.”  Mycologia 64: 15-35. 
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INDEX
	
		KEY ENTRY	PAGE

AURISCALPIUM  Gray
	A. vulgare  Gray	3b	2, 5

BANKERA  Coker & Beers ex Pouzar
	B. fuligineoalba  (J.C. Schmidt: Fr.) Pouzar	101a	3, 6
	B. violascens  (Alb. & Schwein.) Pouzar	101b	3, 6
	  = Bankera carnosa  (Banker) Snell, E.A. Dick, & Taussig

HERICIUM  Pers.
	H. abietis  (Weir ex Hubert) K.A. Harrison	203a	2, 6
	H. americanum  Ginns	203b	2, 6
	H. coralloides  (Scop.: Fr.)  Pers.	202a	2, 6
	H. erinaceus  (Bull. ex Fr.) Pers.	201a	2, 6

HYDNELLUM  P. Karst.    (see also Notes on Hydnellum, a separate document)
	H. aurantiacum  (Batsch: Fr.) P. Karst.	4
	H. caeruleum  (Hornem. ex Pers.) P. Karst.	4
	H. peckii  Banker	4
	H. regium  K.A. Harrison	4
	H. scrobiculatum  (Fr.) P. Karst.	4
	H. suaveolens  (Scop.: Fr.) P. Karst.	4

HYDNUM  L.
	H. repandum  Fr.	401a	2, 10
	  = Dentinum repandum  (Fr.) Gray
	  = Hydnum washingtonianum  Ellis & Everh.
	H. umbilicatum  Peck	401b	2, 10
	  = Dentinum umbilicatum  (Peck) Pouzar

PHELLODON  P. Karst.
	P. atratus  K.A. Harrison	302a	2, 8
	P. melaleucus  (Fr.) P. Karst.	302b	2, 8
	P. tomentosus  (Fr.) Banker	301a	2, 8

PSEUDOHYDNUM  P. Karst.
	P. gelatinosum  (Scop.: Fr.) P. Karst.	1a	1, 5

SARCODON  Quel. ex P. Karst.     (see also Key to Sarcodon)
	S. calvatus  (K.A. Harrison) K.A. Harrison	3
	S. fumosus  Banker	3
	S. fuscoindicus  (K.A. Harrison) Maas Geest.	3
	S. imbricatus (L.: Fr.) P. Karst.	3
	S. scabrosus  (Fr.) Quel.	3
	S. squamosus  (Schaeff.) Quel..	3
	S. stereosarcinon  Wehm.	3

-  END  -