Abstract
Across the Mediterranean biodiversity hotspot, our knowledge of fungal diversity is still fragmentary, and the eastern part of the basin remains poorly explored. This is particularly the case in Lebanon, where macrofungal diversity has never been subject to molecular-based investigation. A first checklist was published in 1957 and updated in 1996, based on morphological identification of specimens. In an effort to narrow this gap of knowledge, we designed a field survey in Akkar, north Lebanon in Abies cilicica, Quercus calliprinos and Quercus cerris old-growth stands, carried out between 2018 and 2019. Three sampling plots were monitored in each ecosystem. By combining morphological identification and molecular analysis of 105 collected samples, 79 species were identified, including 62 (i.e., 78.5%) new records for Lebanon, and eight putative undescribed species. Species diversity was the highest under Quercus calliprinos and lowest under Abies cilicica. Most species were encountered in just one ecosystem type, and only 7 were recorded in two ecosystems. These results highlight the overlooked fungal diversity in this part of the eastern Mediterranean hotspot, and the importance of Lebanese forests for biodiversity conservation. Our results also call for further investigation, in particular under endemic tree hosts, to increment the still incomplete national checklist of macrofungi in Lebanon.