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Mountains play a crucial role in the origin and maintenance of Neotropical biodiversity, but there are still unanswered questions about the diversification of the campos rupestres (CR), an herbaceous-shrubby sky-island vegetation in eastern South America. For orchids distributed across this disjunct rock habitat, difficulties with distinguishing morphological taxa add an additional challenge to disentangling the history of divergence. Here, we combined the power of ddRAD genomic data with broad sampling of Bulbophyllum sect. Didactyle (Orchidaceae), across the CR and other Neotropical outcrops, to estimate evolutionary relationships and evaluate the biogeography of the group’s diversification. Although genetic lineages generally align with geographic disjunctions, we also observe distantly related lineages within some previously recognized species. For such taxa, their lack of monophyly and a shared regional divergence pattern suggests a complex history that may include unrecognized diversity. When viewed through the lens of morphological variability, our study raises intriguing questions about the persistence and permeability of species barriers among orchid populations. These results, in addition to the recency of the divergence history of B. sect. Didactyle, provide insights about hypothesized community level vs. species-specific paths of diversification across the Neotropical sky-islands of the CR.

To achieve the ambitious goals of the UN Decade on Ecosystem Restoration, restoration frameworks should embrace the diversity of ecosystems found on Earth, including open-canopy ecosystems, which have been largely overlooked. Considering the paucity of scientific foundations promoting restoration science, policy, and practice for open tropical ecosystems, we provide overarching guidelines to restore the campo rupestre, a Neotropical, open megadiverse grassland that has been increasingly threatened by multiple human activities, especially mining. Restoration techniques for tropical grasslands are still at its infancy, and attempts to restore campo rupestre have had, so far, low to moderate success, highlighting the need for a tailored restoration framework. In a scenario of increasing degradation and scarcity of on-site restoration experiments, we propose 10 principles to improve our ability to plan, implement, and monitor restoration in campo rupestre: (1) include socioeconomic dimensions, (2) implement active restoration, (3) keep low soil fertility, (4) restore disturbance regimes, (5) address genetic structure and adaptation potential, (6) restore geographically restricted and specialized ecological interactions, (7) incorporate functional approaches, (8) use seed-based restoration strategies to enhance biodiversity, (9) translocation is inevitable, and (10) long-term monitoring is mandatory. Our principles represent the best available evidence to support better science and practice for the restoration of campo rupestre and, to some extent, can be useful for other megadiverse, fire-prone, and nutrient-poor ecosystems.

The campo rupestre is a Neotropical azonal vegetation. Its disjoint distribution and the fact that it is an old climatic buffered infertile landscape (OCBIL) have been associated with the high diversity and endemism observed in this environment. Here, we tested whether a micro-endemic species from campo rupestre shows: (1) limited zygotic gene flow; (2) lower gametic than zygotic gene flow structure; (3) substrate-driven genetic structure and (4) no evidence of Pleistocene local extinction or recolonization. By sequencing intergenic plastid regions, phenotyping inter simple sequence repeats (ISSR) and modelling present and past species suitability distributions for Vellozia auriculata we conclude that (1) zygotic gene flow is limited; (2) gametic gene flow is recurrent, but limited by elevation and distance; (3) there is no support for genetic structure driven by substrate and (4) Pleistocene climatic changes did not restrict the species to refugia, with local persistence. As long-term gene flow restrictions may lead to differentiation and speciation, our data helps to corroborate that the campo rupestre is both a cradle (due to low zygotic gene flow, prolonged isolation and consequent differentiation) and a lineage museum (due to local survival during climate oscillations). We highlight two distinct evolutionarily significant units (ESU), providing information for better conservation practice.