North American Fungi Volume 9, Number 8, Pages 1-7 Published October 13, 2014 A new species of Russula, subgenus Compactae from California David Arora1 and Nhu H. Nguyen2 1P.O. Box 672, Gualala, CA 95445; 2Dept. of Plant and Microbial Biology, University of California at Berkeley, Berkeley, CA, 94720-3102 Arora, D., and N. H. Nguyen. 2014. A new species of Russula, subgenus Compactae from California North American Fungi 9(8): 1-7. http://dx.doi.org/10.2509/naf2014.009.008 Corresponding author: David Arora [email protected]. Accepted for publication September 30, 2014. http://pnwfungi.org Copyright © 2014 Pacific Northwest Fungi Project. All rights reserved. Abstract: A new species of Russula, subgenus Compactae, is described growing in association with coast live oak (Quercus agrifolia) in California. This species has previously been referred to locally as Russula subnigricans Hongo and Russula eccentrica Peck, but morphological and DNA evidence show that it is a distinct species which we call R. cantharellicola. Our analysis shows that there are multiple clades of what is called R. subnigricans, and that the California species clearly falls within one of those clades. As R. subnigricans has caused deaths in Japan, China, and Taiwan, the California species should be cautioned as potentially dangerous to those who consume it. Key words: Russula, California, fungal diversity, toxicity Introduction: Russula Pers. (Russulales, stands apart from the rest of the genus in having Russulaceae) is a large, prominent, and large, persistent, dull-colored, hard-bodied important genus of ectomycorrhizal woodland basidiocarps, numerous lamellulae alternating mushrooms. Russula subg. Compactae (Fr.) Bon with the lamellae, and a poorly differentiated 2 Arora & Nguyen. A new species of Russula. North American Fungi 9(8): 1-7 pileipellis that does not separate easily from the this California taxon with a noticeable affinity for context. Ongoing molecular studies reveal a Cantharellus differs from both R. eccentrica and number of clades within subgenus Compactae R. subnigricans, and we describe it as a new (Bart Buyck, pers. comm.), each embracing well- species. known species with blackening basidiocarps such as R. nigricans Fr., R. densifolia Secr. ex Gillet, Materials and Methods and R. albonigra (Krombh.) Fr., plus several Morphological examinations.—A description was additional clades with sequences called R. drawn up from fresh material with special subnigricans Hongo – an Asian species that emphasis on the staining reactions, and the stains dingy reddish in age but does not blacken. collections were photographed in the field. Spores and other micro characteristics were While several of the blackening species are widely examined at magnifications of 400× and 1000×. eaten, from Mexico to Russia, China and DNA extraction and sequencing.—DNA was Thailand (Boa 2004), R. subnigricans is notable extracted from powdered tissue of dry for being deadly poisonous, having caused basidiocarps, hydrated with 2% CTAB numerous fatalities in Japan, southern China and (cetyltrimethylammonium bromide) buffer, with Taiwan due to rhabdomyolysis (Lee et al. 2001; 2% PVP (polyvinylpyrrolidone), followed by Matsuura et al. 2009; Chen et al. 2014). standard methods for chloroform extraction and ethanol precipitation. DNA was extracted from oak root-tips using the Sigma Extract-N-Amp kit Shaffer (1962) included R. subnigricans in his (Sigma Aldrich, St. Louis, MO). The ITS region treatment of “Russula subsection Compactae” was amplified using the standard fungal specific but did not cite any collections from North primers ITS1F (Gardes & Bruns 1993) and ITS4 America. Since the 1970s the senior author has (White et al. 1990) using dilute DNA template. repeatedly collected a species closely resembling Sequences were produced using the standard R. subnigricans in the oak woodlands of central BigDye Terminator v3.1 Kit and were run on an coastal California, always in association with the ABI Prism 3700 Genetic Analyzer (Life California oak chanterelle, Cantharellus Technologies) using the above PCR primers. Each californicus Arora & Dunham (2008). Arora automated sequence was examined and manually (1986) referred this species to the “Russula interpreted, and the ambiguous bases were subnigricans group” pending further study. corrected using Sequencher 4.7 (Gene Codes Weber & Smith (1985) depicted R. subnigricans Corporation). All sequences were deposited in from the southern USA, but Bills (1985) showed GenBank as KF306036–KF306039. that the southern USA taxon was already named R. eccentrica Peck (Peck 1911) based on Phylogenetic methods.— ITS sequences were specimens collected in Missouri, USA, and that taken from GenBank that had a similarity score this name had priority over R. subnigricans of greater than 90% to the taxon of interest using should the two species prove to be identical. BLAST. The sequences were from both vouchered Thiers (1998), in his treatise on California and environmental samples such as Russula, applied the name R. eccentrica to the ectomycorrhizal root-tips. Russula cerolens California species. His description fits that of the Shaffer was chosen as the outgroup. Sequences species described by Arora (1986) as “Russula were aligned using MAFFT (Katoh et al. 2002) subnigricans group,” but Thiers cited only one and the alignment was manually optimized. The collection and we were unable to locate it in San final dataset was restricted to members of Francisco State University (SFSU) for subgenus Compactae and analyzed using sequencing. In this study we determined that maximum likelihood with the GTRGAMMA model Arora & Nguyen. A new species of Russula. North American Fungi 9(8): 1-7 3 of nucleotide substitution in RAxML (Stamatakis Mycobank : MB804625; GenBank KF306036 2006). Maximum likelihood bootstrapping was (ITS sequence) performed locally in RAxML using stringent Etymology: cantharelli- (Latinized Greek), bootstrapping criteria with 1000 replications referring to the chanterelle genus Cantharellus; (Stamatakis 2006). cola (from L. colere, to dwell among). Results Pileus 8–30 cm broad when mature, broadly Morphological examination of specimens showed convex with a depressed center becoming plano- that the new taxon differed from other Russula depressed or vase-shaped; pellicle not easily species described from California and the eastern separable from the context; the surface slightly USA, including R. eccentrica. Phylogenetic viscid when moist, glabrous, whitish when young reconstruction of the available data for subgenus but soon developing pale smoky-brown or dingy Compactae (FIG. 1) showed that there are many reddish-brown shades, sometimes also with clades, with one or multiple names, and some slight ochre stains or a mixture of all the above without names and only from ectomycorrhizal colors but not blackening; margin at first root-tips. The name R. subnigricans has been inrolled, smooth, not becoming striate. Flesh broadly applied and can be found in several thick, crisp, white, typically bruising slowly dingy clades. The new California taxon described here reddish (this process may take one to 20 minutes is in a well-supported clade (93%), with or more) and sometimes hardly at all, then specimens of “Russula subnigricans” from Japan usually slightly browner or grayer within an hour and Korea, R. eccentrica from Tennessee, and R. but not blackening; odor strong and unpleasant polyphylla Peck from an unknown locality. The at maturity or upon drying; taste mild to slightly new taxon is sister to a specimen of “Russula bitter. subnigricans” from Japan, and the available phylogenetic information indicates that these are Lamellae thick, brittle, fairly close, usually two different taxa. Using phylogenetic and alternating long and short, adnate to slightly morphological data the new species is described decurrent, at first pallid but soon developing below. sordid reddish or brick-red stains; in weathered specimens often entirely dark, dull reddish. Russula cantharellicola D. Arora & N.H. Stipe 5–13 × 3–7 cm thick, hard, firm, rigid, Nguyen, sp. nov. FIGS. 2 & 3 solid, equal or with a tapered base, the surface glabrous; white at first, staining sordid reddish Medium-sized to large basidiocarps with white and/or smoky-brown with age or handling but pileus becoming brownish, sordid reddish or not blackening. grayish-brown, white gills that stain sordid reddish and eventually become entirely sordid red, sturdy stalk, unpleasant odor when mature, Spores deposit white (Codice Romagnesi Ia), and subglobose to ovoid, weakly ornamented spores 7–10 × 6–8 μm (avQ=1.2, n=30), spores. subglobose, broadly ellipsoid to ovoid, weakly ornamented with low (<0.5 μm) amyloid warts Holotype: USA, California, Santa Cruz County, connected in some places by very fine lines (the near Aptos, with Quercus agrifolia and amyloid warts are so small and close together Cantharellus californicus. 36.983069°N that the whole spore appears weakly amyloid). 121.860901°W. 1 November 2011, Arora 11404 Pleurocystidia and cheilocystidia 50–90 × 6–12 (SFSU); Isotype: UC1999420. μm, elongate-fusoid. Basidia 48–63 μm long, 5– 4 Arora & Nguyen. A new species of Russula. North American Fungi 9(8): 1-7 7.5 μm thick; sterigmata 5–6.3 μm long. The name R. adusta Pers. (Fr.) has been applied Pileocystidia not observed. Pileipellis 200–334 to one or more conifer-associated species in μm thick, embedded in a clear layer of gluten up western North America that may exhibit a slight to 250