1155 Mycologia, 95(6), 2003, pp. 1155–1170.  2003 by The Mycological Society of America, Lawrence, KS 66044-8897 Phylogenetic relationships of European Phlegmacium species (Cortinarius, Agaricales)* S. Garnica 1 M. Weiß Lehrstuhl fu ¨r Spezielle Botanik und Mykologie, Botanisches Institut, Universita ¨t Tu ¨bingen, Auf der Morgenstelle 1, D-72076 Tu ¨bingen, Germany B. Oertel Institut fu ¨r Gartenbauwissenschaft, Universita ¨t Bonn, Auf dem Hu ¨gel 6, D-53121 Bonn, Germany F. Oberwinkler Lehrstuhl fu ¨r Spezielle Botanik und Mykologie, Botanisches Institut, Universita ¨t Tu ¨bingen, Auf der Morgenstelle 1, D-72076 Tu ¨bingen, Germany Abstract: Phylogenetic relationships of 54 European Phlegmacium species, including members of most of the sections of classical systematics, were studied, in- tegrating macro-, micromorphological and chemical characters of the basidiomes, as well as molecular phylogenetic analysis of nuclear rDNA sequences. Mi- croscopical structures of the basidiomes were studied by light microscopy. Basidiospore morphology was ex- amined by scanning electron microscopy. Internal- transcribed spacers (ITS 1 and 2, including the 5.8S) and the D1/D2 (LSU) regions of nuclear rDNA were sequenced and analyzed with a Bayesian Markov chain Monte Carlo approach. Many subgroups de- tected by the molecular analysis are related to groups known from classical systematical concepts. Among others, these subgroups were significantly supported: i) a group containing most of the members of section Fulvi ss. Brandrud and the species Cortinarius arcu- atorum, C. dibaphus and C. multiformis; ii) a group comprising taxa of section Calochroi ss. Brandrud and the species C. fulvocitrinus and C. osmophorus; iii) a group containing species of section Glaucopodes ss. Brandrud and C. caerulescens; iv) a group including members of section Phlegmacioides ss. Brandrud; v) a group that includes the species C. cephalixus, C. nan- ceiensis and C. mussivus. Stipe shape, color of flesh, pigment contents, KOH reaction on pileipellis and gelatinous layer, degree of development of a gelati- nous layer on the pileipellis, and pileipellis structure Accepted for publication April 24, 2003. 1 Corresponding author. E-mail: sigisfredo.garnica@ uni-tuebingen.de * In memoriam Meinhard M. Moser, 1924–2002. were useful characters in delimiting subgroups in Phlegmacium, while basidiospore morphology was sig- nificant at species level. With the exception of C. glaucopus, C. infractus and C. scaurus, ITS and D1/ D2 sequences obtained from collections of the same species from different geographical origins showed very little variation. Our molecular and morphologi- cal analyses suggest revisions of the traditional con- cepts of the subgenus Phlegmacium in Europe. Key words: D1/D2 domains, Europe, ITS, LSU, molecular phylogeny, morphology, nuc rDNA, sys- tematics INTRODUCTION Phlegmacium Fr., a subgenus of Cortinarius, includes species with relatively fleshy basidiomes with vivid col- ors, a viscid to glutinous pileus surface and a dry stipe. Many Phlegmacium species have a wide distri- bution in Europe and occur in ectomycorrhizal as- sociation with coniferous and deciduous trees. Some species are supposed to be even more widespread and reach North America (Moser et al 1994, 1995; Moser and Ammirati 1996, 1997, 1999). On the other hand, other Phlegmacium species show a limited dis- tribution, mainly due to high host-tree specificity, or specific climatic or edaphic requirements. Since Fries (1821) introduced the name Phlegma- cium as a tribus of the genus Agaricus, many mycol- ogists have contributed to the systematics and tax- onomy of the Phlegmacium species in Europe, group- ing them in a separate genus (e.g., Wu ¨ nsche 1877, Fayod 1889, Earle 1909, Ricken 1915, Moser 1960) or in a subgenus of Cortinarius (e.g., Fries 1836– 1838, 1878–1884; Moser 1983; Moe ¨nne-Loccoz et al 1990–2001; Bidaud et al 1994; Brandrud et al 1990– 1998). Modern classification systems recognize Phleg- macium as a subgenus of Cortinarius. Species delim- itations in Phlegmacium traditionally have been based almost exclusively on ‘‘field recognition’’, e.g., col- oration of pileus and lamellae, as well as macrochem- ical tests combined with basidiospore morphology (e.g., Moser 1960, 1983, 1986; Moe ¨nne-Loccoz et al 1990–2001; Bidaud et al 1994). Attempts to increase the number of characters used for taxonomic pur- poses in Phlegmacium have been made by Oertel (1984), Oertel and Laber (1986), Steglich et al