New species of the Botryosphaeriaceae discovered on Baobabs and other native trees in Western Australia

Abstract

New species of the Botryosphaeriaceae were identified and described in this study. Isolates were collected from baobab (Adansonia gibbosa) and surrounding endemic tree species growing in north-western Australia. Cultures resembling those of the Botryosphaeriaceae were predominantly endophytes isolated from apparently healthy wood and bark, but some also came from dying branches. Based on phylogenetic analyses of ITS and EF1-a sequence data, isolates were placed in clades representing the genera Pseudofusicoccum, Botryosphaeria, Lasiodiplodia, Dothiorella and Neoscytalidium. Sequence comparison with known species of the Botryosphaeriaceae revealed that several isolates obtained in this study represent undescribed species. The new taxa were characterised based on ITS and EF1-a sequence data combined with anamorph morphology. Six new species are recognised including three Pseudofusicoccum spp., a Botryosphaeria sp., a Lasiodiplodia sp. and a Dothiorella sp. Neoscytalidium isolates from this study formed a separate sub-clade in this genus, but a lack of sequences for previously described Neoscytalidium spp. Precludes their identification at this stage. Very few studies have been conducted to identify Botryosphaeriaceae on trees in natural ecosystems, and almost nothing is known regarding the fungi on baobabs. Thus, the relatively large number of new species emerging from this study is not surprising. The role of these fungi in the ecology of the trees from which they were collected will be considered in future studies.