Hydnum repandum group L. group
sweet tooth
Hydnaceae

Species account author: Ian Gibson.
Extracted from Matchmaker: Mushrooms of the Pacific Northwest.

Introduction to the Macrofungi

Photograph

© Michael Beug     (Photo ID #14678)


Map

E-Flora BC Static Map

Distribution of Hydnum repandum group
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Species Information

Summary:
Hydnum repandum itself has not been found in North America. The term Hydnum repandum group is an artificial group to describe what we have been calling Hydnum repandum in North America (excluding Hydnum umbilicatum). |Features of the Hydnum repandum group include a convex to depressed cap up to 17cm across or larger that is tan to pale orange or even reddish-tawny; white flesh; whitish to pale orange teeth; a relatively short stem that is cap-colored or paler; a bruising reaction to orange on cap, in cap flesh, and on the teeth and stem; white spore deposit; and microscopic characters. |Following the molecular work of Niskanen(10), Hydnum repandum is well documented only from Europe. According to Niskanen(10), the most closely related species in North America is Hydnum neorepandum [here considered a synonym of Hydnum washingtonianum following Swenie(1)] - Niskanen(10) documented that species from NL and from an ectomycorrhizal root tip in CA, but they also described several other new Hydnum species using Pacific Northwest collections. |Hydnum olympicum will also belong to this group until it is clear how to tell it apart from Hydnum washingtonianum without measuring spores. Hydnum melleopallidum can be similar and spores are similar, but the fruitbodies are smaller than those of Hydnum washingtonianum. |Hall found what he called the type variety (described below) in WA as well as two other varieties (the first only tentative because it is basically an intermediate between H. repandum and H. umbilicatum): 1) Dentinum repandum var. macrosporum Hall & Stuntz nom. prov. (spores 9.0-9.8 x 7.6 microns) and cap "pinkish-buff" to "cinnamon-buff" (like var. repandum and unlike Hydnum umbilicatum, var. macrosporum has a large convex or slightly depressed cap), and 2) Dentinum repandum var. album (Quel.) K.A. Harrison = Hydnum repandum var. album (Quel.) Rea, with white cap and smaller spores 6.7-7.3 x 4.7-6.7 microns, (Hall).
Odor:
mild (Arora), none or slightly fungoid (Hall)
Taste:
mild to somewhat bitter or peppery, (Arora), none (Hall), mild to rather sharpish (Breitenbach), older specimens may taste bitter (Sept(1))
Microscopic:
spores 6.5-9 x 5.5-8 microns, broadly elliptic to nearly round, smooth, (Arora), spores 8.0-8.7 x 6.2-7.0 microns, round to subelliptic, smooth, inamyloid; basidia 3-4-spored, 45-50 x 4.7-6.7 microns, clavate; cystidia absent; hyphae 2.7-4 microns wide, thin-walled, with abundant clamp connections, (Hall), spores 7-8.5 x 6-7 microns, (Bessette), spores 6.5-8.5 in diameter, round, (Phillips), spores 6-7 x 5-6 microns (Lincoff(1)), spores 7-8 x 6.3-7.4 microns, var. albidum 7-8.5 x 5.5-7 microns, (Coker)
Spore Deposit:
white (Arora)
Notes:
H. repandum group is widely distributed in United States and Canada, including FL, NC, NY, PA, and TN, and is common in Europe, (Coker). There are collections from WA, OR, and CA at Oregon State University, and collections from BC at Pacific Forestry Centre and University of British Columbia. The University of Washington also has collections from AK. It has been reported from ID by Andrew Parker, pers. comm.
EDIBILITY
yes, peppery taste disappears with cooking, (Arora)

Habitat and Range

SIMILAR SPECIES
Hydnum umbilicatum has a smaller cap, 2-6.5cm, commonly 4.5cm across, that is abruptly umbilicate, a long and slender stem 0.5-1(1.5)cm wide, and larger spores (9.0-10.0 x 7.0-8.6 microns), (Hall). H. umbilicatum is generally smaller, has a darker orangish, distinctly umbilicate cap, longer, more slender stem, and slightly larger spores (7.5-10 x 6.5-8.5 microns instead of 6.5-8.5 x 6-8.5 microns), (Trudell(4)).
Habitat
single, scattered, gregarious, or in troops under hardwoods and conifers, throughout the mushroom season but in California peaking in late winter or early spring, (Arora), single or gregarious in duff and moss under Pseudotsuga (Douglas-fir), Abies (fir), and Tsuga (hemlock), (Hall), summer and fall (Miller)