Eco‐phylogenetic study of Trebouxia in southern Africa reveals interbiome connectivity and potential endemism in a green algal lichen photobiont

作者：Ian D. Medeiros, Alicia Ibáñez, A. Elizabeth Arnold, Terry A. Hedderson, Jolanta Miądlikowska, Adam Flakus, Ignazio Carbone, Scott LaGreca, Nicolas Magain, Edyta Mazur, Reinaldo Vargas, József Geml, Maya Kaup, Gillian Maggs‐Kölling, Shuzo Oita, Jaya Seelan Sathiya Seelan, Elizaveta F. Terlova, Erik Hom, Louise A. Lewis, François Lutzoni · 发表于：American Journal of Botany · 年份：2024 · DOI：10.1002/ajb2.16441 · 被引用次数：9 · 研究领域：Lichen and fungal ecology、Biocrusts and Microbial Ecology、Mycorrhizal Fungi and Plant Interactions

PREMISE: Southern Africa is a biodiversity hotspot rich in endemic plants and lichen-forming fungi. However, species-level data about lichen photobionts in this region are minimal. We focused on Trebouxia (Chlorophyta), the most common lichen photobiont, to understand how southern African species fit into the global biodiversity of this genus and are distributed across biomes and mycobiont partners. METHODS: We sequenced Trebouxia nuclear ribosomal ITS and rbcL of 139 lichen thalli from diverse biomes in South Africa and Namibia. Global Trebouxia phylogenies incorporating these new data were inferred with a maximum likelihood approach. Trebouxia biodiversity, biogeography, and mycobiont-photobiont associations were assessed in phylogenetic and ecological network frameworks. RESULTS: An estimated 43 putative Trebouxia species were found across the region, including seven potentially endemic species. Only five clades represent formally described species: T. arboricola s.l. (A13), T. cf. cretacea (A01), T. incrustata (A06), T. lynniae (A39), and T. maresiae (A46). Potential endemic species were not significantly associated with the Greater Cape Floristic Region or desert. Trebouxia species occurred frequently across multiple biomes. Annual precipitation, but not precipitation seasonality, was significant in explaining variation in Trebouxia communities. Consistent with other studies of lichen photobionts, the Trebouxia-mycobiont network had an anti-nested structure. CONCLUSIONS:...