Russula phoenicea Bazzicalupo, D. Miller & Buyck.

Index Fungorum number: IF553819 Facesoffungi number: FoF 03652

Etymology: phoenix-like, a reference to its pleasing colouration.

Holotype: Ben Woo 919 (WTU, sub nr. F-038577)

Pileus 3.5–12 cm diameter, slightly depressed in the centre and with weakly striate margin; surface smooth, tinged with pale shades of pink, greyish pink, vinaceous or green, often with some patches of paler discolouration. Lamellae adnate, equal or with few lamellulae and few to no bifurcations, normally spaced (ca 1 L/mm), white to pale cream (of Woo specimens, ‘white’ recorded for ~85%; ‘cream’ for ~15%); gill edge concolourous, even. Stipe mostly equal to cap diameter, cylindrical, with wrinkled surface, translucent and fragile; interior mostly soft. Context unchanging or turning pale pink with FeSO4. Odor none. Taste mild to faintly acrid in gills and flesh (of Woo specimens; flesh at least somewhat hot in ~15%; gills somewhat hot in ~27%). Spore deposit very pale (of Woo specimens, Crawshay A ~75%; B–C ~25%). Spores broadly ellipsoid, (6.8–)8.09–8.1–8.16(–9.4) × (5.3–)6.52–6.5–6.59(–8) µm, Q = (1–)1.15–1.24–1.25(–1.5); ornamentation subreticulate, composed of amyloid, conical warts, (0.3–)0.89–0.9–0.92(–1.6) µm high and sometimes slightly curved and the tips, with low and thin interconnections; suprahilar spot not highly amyloid although present as a patch. Basidia (33.5–)40.5–45–49.5(–55) × (8.5–)10–11–12(–13) µm, 4–spored, stout and clavate with swollen top; basidiola also stout and clavate. Lamellar trama mainly composed of sphaerocytes; cystidioid hyphae present. Hymenial cystidia 80–95 × 8–10 µm, broadly clavate to fusiform, mostly clavate near the gill edge, obtuse–rounded at the top, SV+ and turning dark purple in sulfovanillin (although ~20% of Woo specimens showed a grey reaction). Pileipellis not sharply delimited from the underlying context of filamentous hyphae and sphaerocytes; suprapellis very similar between cap centre and margin, composed of loosely arranged, branching hyphal terminations, with cylindrical terminal cells. Pileocystidia at the cap surface (20–)48–55–60(–62) × (3.5–)5–6–7(–8) µm, sometimes slightly constricted at the tips; contents refringent, SV+, continuing as cystidioid hyphae with refractory contents in subpellis and trama. Acidoresistant incrustations absent. Clamp connections absent in all parts.

Habitat and distribution: Pseudotsuga menziesii (Douglas fir) was consistently recorded near collections, sometimes mixed with Pinus contorta (also known as lodgepole pine, shore pine or twisted pine), Picea sitchensis (Sitka spruce), Tsuga heterophylla (western hemlock) and Abies (true firs). Only known from the Pacific Northwest (USA: Oregon, Washington; Canada: British Columbia).

Examined material: CANADA, British Columbia, Golden Ears Provincial Park, in camp loop “Kalmia”, 122.543056˚W, 49.245278˚N, 100 m alt., 04 Oct 1997, B. Woo BW706, F-039284 (WTU), GenBank ITS2: KX813394; U.S.A., Oregon State, East Devils Lake Park, Lincoln City, 123.997778˚W, 44.966667˚N, 8 m alt., 10 Nov 1996, B. Woo BW675, F-039222 (WTU), GenBank ITS2: KX813372; ibidem, South Beach State Park, Newport, 124.060556˚W, 44.602222˚N, 15 m alt., 10 Nov 1996, B. Woo BW682, F-038547 (WTU), GenBank ITS2: KX813376; Washington State, 3rd Beach Trail, La Push, 124.165˚W, 47.888889˚N, 6 m alt., 30 Oct 1998, B. Woo BW770, F-038905 (WTU), GenBank ITS2: KX813437; ibidem, Old Fort Townsend State Park, 122.790556˚W, 48.074444˚N, 60 m alt., 27 Oct 1997, B. Woo BW744, F-038937 (WTU), GenBank ITS2: KX813421; ibidem, Sloan Creek, 121.254˚W, 48.0575˚N, 630 m alt., 28 Sep 1997, B. Woo BW695, F-038577 (WTU), GenBank ITS2: KX813388; ibidem, 23 Sep 2001, B. Woo BW919, F-038477 (WTU, holotype), GenBank ITS2: KX813551; ibidem, Talapus Lake Trail, 121.585˚W, 47.401˚N, 805 m alt, 17 Oct 1997, B. Woo BW730, F-038215 (WTU), GenBank ITS2: KX813410.

Notes: Russula phoenicea corresponds to Clade 1 in our phylogeny, to Woo sp. 26 in Bazzicalupo et al. (in press) and to UNITE SH DOI:

In the Pacific Northwest, R. phoenicea could most easily be confused with R. hypofragilis. (described below) but the two species are not sister taxa. Host association may differentiate the two. Both were found in mixed conifer stands, however, R. hypofragilis was consistently reported in the presence of Abies, while R. phoenicea was consistently recorded with Pseudotsuga. Morphological characteristics overlapped although gills in R. hypofragilis were more frequently recorded as being at least somewhat hot, and specimens of R. hypofragilis were less likely to have olive or green tones compared with R. phoenicea. Cap colour in both species ranged from shades of purples, greens and pink grey, and sizes of their microscopic features overlapped. The red to yellow cap colours so typical of R. montana Shaffer (= griseascens (Bon & Gaugué) Marti, see Bazzicalupo et al. (in press)), R. emetica and other species in the clade were less common than purplish or greenish tones in both R. phoenicea and R. hypofragilis. While flesh and gill tastes were hot in >90% of specimens of R. montana and in 100% of specimens of R. emetica, flesh and gill taste of R. phoenicea was usually mild. The macro- and micro-morphology of R. phoenicea overlapped with descriptions from Sarnari (1998–2005) for R. fragilis Fr., and R. aquosa LeClair, however these latter species are at this time unknown from the Pacific Northwest based on UNITE SH. Identical (100% match) ITS2 sequences to R. phoenicea have only been found in the Pacific Northwest [Canada: British Columbia (EU057098, FJ152483, KP889552, KP889829); Sooke Reservoir, Victoria, BC (UDB024994); Capilano Regional Park, Vancouver, BC (KC581327); Campbell River, BC (KP406551)]. The only other sequence available as of March 2017 with a 1%-3% difference was KF835445 from India.

Related west coast species (see Buyck et al. 2015) include R. crenulata Burl., which was described from Oregon (Burlingham 1913) but differs in its very pale, white to yellowish cap colour, distinctly crenulate gill edges and very acrid taste; R. cremoricolor Earle, which is similarly coloured and equally hot but is an oak-associated species described from California (Earle 1902); and R. stuntzii Grund, a whitish and very acrid species that is phylogenetically closer to R. consobrina and R. helodes (see (Bazzicalupo et al. in press)). The more reddish R. subveternosa Sing., an acrid species with darker and differently ornamentated spores described from Populus stands in Wyoming (Singer 1939) probably belongs to a different clade.

Maximum likelihood phylogeny of nine new species of Russula. Specimen codes and morphological descriptions are available through <>. Bootstrap support 70% or more is indicated by thickened black branches. The grey shading of taxa indicates the samples of the new species described. Holotypes are designated along with their collection numbers and GB accessions. Clade numbers are assigned to new species and the total number of Woo’s collections of each new species is in parentheses. ‘CT’ next to taxon name indicates the sample was confirmed with a type specimen sequence; an asterisk ‘*’ indicates a sample from the backbone constraint tree. GenBank sequences R. aurea, R. leprosa, R. sardonia, R. rosea, and R. pseudointegra were re-named in this figure based on recent sequencing of the species by author BB.


Morphology and specimen distribution of Clade 1 Russula phoenicea (Woo sp. 26). BW followed by numerals designate Ben Woo samples. a Photo by B. Woo, BW770, scanned image from WTU. b Distribution of specimens of the Woo collections in Pacific Northwest States and Provinces. c–h Micromorphology, all 1000x magnification. c Spores in median optical section and surface view in Melzer’s reagent (c1–c2 BW675; c3–c4 BW682; c5–c6 BW695; c7–c8 BW744; c9–c10 BW744; c11–c12 BW730). d Hymenial cystidium (BW695). e–f Basidia (BW706, BW744). g–h Cap cuticle terminal cells with refringent contents (BW695, BW682). Scale bars 10 µm