Phytotaxa 270 (2): 071–088 http://www.mapress.com/j/pt/ Copyright © 2016 Magnolia Press Article PHYTOTAXA ISSN 1179-3155 (print edition) ISSN 1179-3163 (online edition) Accepted by Samantha Karunarathna: 7 Jul. 2016; published: 17 Aug. 2016 http://dx.doi.org/10.11646/phytotaxa.270.2.1 71 A molecular analysis reveals hidden species diversity within the current concept of Russula maculata (Russulaceae, Basidiomycota) SLAVOMÍR ADAMČÍK 1* , MIROSLAV CABOŇ 1 , URSULA EBERHARDT 2 , MALKA SABA 3,4 , FELIX HAMPE 5 , MAREK SLOVÁK 1 , JESKO KLEINE 6 , HELGA MARXMÜLLER 7 , SOŇA JANČOVIČOVÁ 8 , DONALD H. PFISTER 3 , ABDUL N. KHALID 4 , MIROSLAV KOLAŘÍK 9 , KAROL MARHOLD 1 & ANNEMIEKE VERBEKEN 5 1 Institute of Botany, Slovak Academy of Sciences, Dúbravská cesta 9, SK-845 23, Bratislava, Slovakia 2 Staatliches Museum für Naturkunde Stuttgart, Rosenstein 1, D-70191 Stuttgart, Germany 3 Farlow Herbarium of Cryptogamic Botany, Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA. 4 Department of Botany, University of the Punjab, Quaid-e-Azam Campus, Lahore 54590, Pakistan. 5 Ghent University, K.L. Ledeganckstraat 35, B-9000 Gent, Belgium 6 Körnerstraße 34, D-04107 Leipzig, Germany 7 Zehentbauernstr. 15, D-81539 München, Germany 8 Comenius University in Bratislava, Faculty of Natural Sciences, Department of Botany, Révová 39, SK-811 02 Bratislava, Slovakia 9 Institute of Microbiology, Czech Academy of Sciences, Vídeňská 1083, CZ-142 20 Praha 4, Czech republic * Corresponding author’s e-mail: slavomir.adamcik@savba.sk Abstract The current generally accepted concept of Russula maculata defines the species by yellow-brownish spots on the basidi- omata, an acrid taste, a yellow spore print and a red pileus. This concept was tested using collections originating from various geographical areas mainly in Europe. Analyses of the ITS region suggested that there were three species within this broad concept. One of them, R. maculata, was identified based on the sequence from the epitype. Two other species, R. nympharum and R. sp., are described here as newly identified species. The European species R. maculata and R. nympharum grow in de- ciduous forests, are similar in their field aspect and are distinctly different in micro-morphological characteristics of spores, pleurocystidia and pileipellis. An Asian species, R. sp., is associated with pine and has smaller basidiomata and spores. These three species form the R. maculata complex and represent the sister clade to the R. globispora complex. This clade consists of species also characterized by a yellow-brownish context discolouration but with a different type of spore ornamentation. All of the other tested species had an acrid taste and yellow spore print but did not have a conspicuous yellow-brownish context discolouration and were placed in various unrelated clades. Key words: DNA barcode, ectomycorrhizal fungi, morphology, Pakistan Introduction The genus Russula Persoon (1796: 100) has more than 200 generally accepted species in Europe (Sarnari 1998, 2005) and more than 750 species worldwide (Kirk et al. 2010). Because of this huge taxonomic diversity, current keys to Russula frequently use intricate combinations of macro- and micro-morphological characteristics and habitat preferences (e.g., Knudsen et al. 2012). Within this complex framework, Russula maculata Quélet (1878: 323) is currently considered a well-defined species with striking macro-morphological characteristics, such as its reddish cap, yellow lamellae due to the yellow spore print, the presence of rusty or yellow-brownish spots on the cap and stipe surface and its fairly firm, acrid context. These characteristics are believed to allow for field recognition of this species (Sarnari 1998). Russula maculata belongs to the generation of early post-Friesian Russula names. The original diagnosis (Quélet 1878) is brief and contains only a rudimentary description of the micro-morphological characteristics, as was typical for descriptions of agaricoid fungi in that period. However, the conspicuous spots on the pileus surface, at which the epithet hints, apparently made the species well recognizable, and it became widely accepted. Later interpretations of