title: Lactarius subgenus Russularia (Basidiomycota, Russulales): novel Asian species, worldwide phylogeny and evolutionary relationships.
abstract: Lactarius subg. Russularia is a large group of milkcaps occurring almost worldwide and dominant in many ecosystems. In this study we focus on new diversity, evolutionary relationships, divergence time, and origin of the subgenus. Six conifer symbionts are described as new to science: Lactarius atrii, L. aurantionitidus, L. dombangensis, L. flavigalactus, L. lachungensis, and L. sikkimensis. Species delimitation is assessed based on the concordance between morphological characteristics and an ITS phylogeny. Infrageneric relationships were studied using a phylogeny constructed from concatenated ITS-rpb2 data using Maximum Likelihood and Bayesian inference. Results show that species in this subgenus do not cluster together according to their geographic origin. Intercontinental sister relationships between Europe/Asia/North America are common but actual conspecificity is rare. This result suggests that allopatric speciation has played an important role within this subgenus. Only few morphological characteristics tend to be phylogenetically informative, with the most important being presence or absence of true cystidia and the pileipellis structure. Two datasets were generated in order to estimate the age of L. subg. Russularia. The results suggest the origin of L. subg. Russularia to be in the Mid Miocene period.
authors.affiliation: Institute of Excellence in Fungal Research, Mae Fah Luang University, 333 Moo 1, Thasud Sub-district, Muang District, Chiang Rai 57100, Thailand; School of Science, Mae Fah Luang University, 333 Moo 1, Thasud Sub-district, Muang District, Chiang Rai 57100, Thailand; Research Group Mycology, Department of Biology, Gent University, K.L. Ledeganckstraat 35, 9000 Gent, Belgium. Electronic address: Komsit.Wisitrassameewong@UGent.be.
authors.forename: Komsit
authors.initials: K
authors.lastname: Wisitrassameewong
authors.affiliation: Department of Ecology and Evolutionary Biology, University of Tennessee, 332 Hesler Biology Building, Knoxville, TN, USA.
authors.forename: Brian P
authors.initials: BP
authors.lastname: Looney
authors.affiliation: Faculty of Environment, Hanoi University of Natural Resources and Environment, 41A Phu Dien Road, Phu Dien Ward, North - Tu Liem District, Hanoi, Viet Nam.
authors.forename: Huyen T
authors.initials: HT
authors.lastname: Le
authors.affiliation: Research Group Mycology, Department of Biology, Gent University, K.L. Ledeganckstraat 35, 9000 Gent, Belgium.
authors.forename: Eske
authors.initials: E
authors.lastname: De Crop
authors.affiliation: Botanical Survey of India, Cryptogamic Unit, P.O. Botanic Garden, Howrah 711103, India.
authors.forename: Kanad
authors.initials: K
authors.lastname: Das
authors.affiliation: Research Group Mycology, Department of Biology, Gent University, K.L. Ledeganckstraat 35, 9000 Gent, Belgium.
authors.forename: Kobeke
authors.initials: K
authors.lastname: Van de Putte
authors.affiliation: Staatliches Museum für Naturkunde Stuttgart, Rosenstein 1, 70191 Stuttgart, Germany.
authors.forename: Ursula
authors.initials: U
authors.lastname: Eberhardt
authors.affiliation: Centre for Mountain Ecosystem Studies, Kunming Institute of Botany, Chinese Academy of Sciences, Lanhei 132, Heilongtan, Kunming 650201, Yunnan, China; World Agroforestry Centre, China & East-Asia Office, 132 Lanhei Road, Kunming 650201, China.
authors.forename: Guo
authors.initials: G
authors.lastname: Jiayu
authors.affiliation: Service of Mycology and Aerobiology, BCCM/IHEM Fungal Collection, Scientific Institute of Public Health, Rue J. Wytsmanstraat 14, Brussels 1050, Belgium.
authors.forename: Dirk
authors.initials: D
authors.lastname: Stubbe
authors.affiliation: Institute of Excellence in Fungal Research, Mae Fah Luang University, 333 Moo 1, Thasud Sub-district, Muang District, Chiang Rai 57100, Thailand; School of Science, Mae Fah Luang University, 333 Moo 1, Thasud Sub-district, Muang District, Chiang Rai 57100, Thailand.
authors.forename: Kevin D
authors.initials: KD
authors.lastname: Hyde
authors.affiliation: Research Group Mycology, Department of Biology, Gent University, K.L. Ledeganckstraat 35, 9000 Gent, Belgium.
authors.forename: Annemieke
authors.initials: A
authors.lastname: Verbeken
authors.affiliation: Naturalis Biodiversity Center, P.O. Box 9517, 2300RA Leiden, The Netherlands.
authors.forename: Jorinde
authors.initials: J
authors.lastname: Nuytinck
mesh_terms: D001208:Asia; D001487:Basidiomycota / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D016000:Cluster Analysis; D004271:DNA, Fungal / Q000737:chemistry / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000737:chemistry / Q000235:genetics; D019143:Evolution, Molecular; D014644:Genetic Variation; D010802:Phylogeny; D012319:RNA Polymerase II / Q000235:genetics; D017422:Sequence Analysis, DNA; D064028:Tracheophyta / Q000382:microbiology
chemical_list: D004271:DNA, Fungal; D021903:DNA, Ribosomal Spacer; D012319:RNA Polymerase II
keywords: Milkcaps; Molecular dating; Molecular evolution; Morphology