摘要
Molecular phylogenetic analyses of LSU rDNA demonstrate monophyly of the genus Melanconiella,and its status as a genus distinct from Melanconis is confirmed.Data of macro-and microscopic morphology,pure cultures and phylogenetic analyses of partial SSU-ITS-LSU rDNA,tef1 and rpb2 sequences revealed 13 distinct species of Melanconiella,six of which are described as new(M.chrysodiscosporina,M.chrysomelanconium,M.chrysorientalis,M.echinata,M.elegans,M.meridionalis).Melanconiella hyperopta var.orientalis is described as a new variety.Diaporthe carpinicola,D.ellisii,D.flavovirens,D.hyperopta and D.ostryae are formally combined into Melanconiella.The name Melanconiella chrysostroma is excluded from Melanconiella,as it is an obligate synonym of Wuestneia xanthostroma.The type of Melanconiella is confirmed as M.spodiaea.Several species are lecto-and/or epitypified.A key to all treated species ofMelanconiella is provided,and the circumscriptions of the genera Melanconis and Melanconiella are emended.Most Melanconiella species revealed by molecular phylogenetic analyses can be well characterised by a suite of morphological traits including ascospore shape,length and width,colour,absence/presence and shape of appendages and the anamorph.Anamorph-teleomorph connections were confirmed by pure culture and DNA data,revealing the presence of a single melanconium-or discosporina-like anamorph for each species.Colony growth was found to be characteristic of the respective species.Melanconiella is shown to be confined to the host family Betulaceae,and all species are found to be highly host-specific,mostly confined to a single host species.The biodiversity ofMelanconiella was determined to be centred on the genus Carpinus with nine species,five of which have been confirmed on C.betulus.Europe appears to be the geographic centre of Melanconiella biodiversity.
基金
We thank Walter Gams for hospitality and excursion support in Italy,Jacques Fournier,Enrique Rubio Domínguez,Sven-Åke Hanson and Larissa Vasilyeva for collecting and communicating Melanconiella specimens,Irmgard Greilhuber and her family for organising and participating in numerous collecting trips together with HV,the fungarium curators of B,BPI,DAOM,G,GZU,K,M,NY,UPS andWfor the loan of specimens,Scott Redhead(DAOM)for providing notes of L.E.Wehmeyer and for allowing DNA extraction from the type specimen of M.echinata,Walter Till(WU)for managing the herbarium loans,and the British Mycological Society for invitation to the BMS Spring Foray 2011 in Yorkshire.
