Reappraisal of the black mildews (Meliolales) on Hevea brasiliensis

The rubber tree (Hevea brasiliensis) is host to several fungal species, including Irenopsis heveae as described by Hansford in 1961, which causes black mildew on leaves. One specimen of Irenopsis heveae from the state of Espirito Santo and two from the state of Para were analyzed and showed some morphological differences. Some structures are similar to morphological characteristics as described and illustrated by Vincens in 1915 for Meliola heveae. Morphological comparisons with the type specimen of I. heveae and the alignment of the nucleotide sequences of the 28S rDNA region, however, indicate that the three samples belong to the same species. According to these data M. heveae and I. heveae are heterotypic synonyms with M. heveae being the older name. As the name I. heveae is already occupied by Hansford, Irenopsis vincensii is proposed as new name for the black mildew on H. brasiliensis. This is the first contribution of molecular sequence data for this species.