RIBOSOMAL DNA-SEQUENCE COMPARISON OF LEPTOGRAPHIUM-LUNDBERGII AND LEPTOGRAPHIUM-TRUNCATUM AND NEOTYPIFICATION OF LEPTOGRAPHIUM-LUNDBERGII

Recent studies have shown that Leptographium lundbergii and L. truncat um are morphologically simi lar. This has led to suggestions that the species, which both occur in Europe and are associated with European s colytid bark beetles, might represent a single taxon. Synonymising the se two species based on their similar morphology has been resisted in the past. This is primarily due to the fact that L. lundbergii is the type species of the genus and it was felt that such a decision should be based on more intensive study PCR amplified DNA fragments of isolat es of L. lundbergii and L. truncatum from numerous geographic origins were compared on the basis of the DNA sequence from the ITS2 region an d part of the 5.8S gene of the rRNA operon. Phylogenetic analyses show that L. lundbergii and L. truncatum isolates group together and separ ate from the outgroups, L. wingfieldii, Ceratocystis fimbriata and C. albofundus. Based on these data and the morphological similarity of th e two species, we conclude that L. truncatum is a synonym of L. lundbe rgii.