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Abstract Understanding biodiversity is critical for the proper conservation of ecosystems experiencing extreme stress from global change. Few other ecosystems are at such high risk of disappearing, especially due to logging and agricultural activities, as the Massif de la Hotte, a chain of mountains in Haiti on the island of Hispaniola, located within the Caribbean Biodiversity Hotspot. We used the hyperdiverse tropical plant family Melastomataceae to understand the biogeographical history and endemism patterns in a major hotspot for the family, the Massif de la Hotte, Haiti. Our goal was to determine the number, timing, and geographical origin of introductions of Melastomataceae (particularly Miconieae) into the Massif de la Hotte. We also aimed to identify whether the Massif de la Hotte and neighbouring ranges on Hispaniola and Cuba were so-called museums or cradles of biodiversity, and determine the extent that areas of high diversity and endemism overlap with currently conserved lands. In total, our analyses uncovered 19 independent dispersal events of Miconieae to the Massif de la Hotte. The Mecranium, Brevycima, and Meriania clades all had rapid radiations consisting of narrow endemics inferred to be of Massif de la Hotte origin. Species of the Chaenopleura clade in the Massif de la Hotte were mostly products of solitary dispersal events from eastern Cuba or the Massif de la Selle. The Massif de la Hotte endemics in the Caribbean Clade were largely the result of dispersal events from central and eastern Cuba. Eastern Cuba is also inferred as the ancestral area for many Massif de la Hotte endemic clades. A total of 25 10 × 10-km grid cells were found by CANAPE to contain significant endemism, with a high proportion of endemism hotspots over the Massif de la Hotte and eastern Cuba. Overlap of these significant CANAPE cells with currently protected areas was high (∼90%). Elucidating phylogenetic diversity and endemism patterns across the vastly different ecosystems of this biodiversity hotspot will aid in our understanding of how these biodiverse forests were formed. 

Abstract—The diverse and spectacular Hibisceae tribe comprises over 750 species. No studies, however, have broadly sampled across the dozens of genera in the tribe, leading to uncertainty in the relationships among genera. The non-monophyly of the genusHibiscusis infamous and challenging, whereas the monophyly of most other genera in the tribe has yet to be assessed, including the large genusPavonia.Here we significantly increase taxon sampling in the most complete phylogenetic study of the tribe to date. We assess monophyly of most currently recognized genera in the tribe and include three and thirteen newly sampled sections ofHibiscusandPavonia,respectively. We also include five rarely sampled genera and 137 species previously unsampled. Our phylogenetic trees demonstrate thatHibiscus, as traditionally defined, encompasses at least 20 additional genera. The status ofPavoniaemerges as comparable in complexity toHibiscus. We offer clarity in the phylogenetic placement of several taxa of uncertain affinity (e.g.Helicteropsis,Hibiscadelphus, Jumelleanthus,andWercklea). We also identify two new clades and elevate them to the generic rank with the recognition of two new monospecific genera: 1)BlanchardiaM.M.Hanes & R.L.Barrett is a surprising Caribbean lineage that is sister to the entire tribe, and 2)AstrohibiscusMcLay & R.L.Barrett represents former members ofHibiscus caesiuss.l.CraveniaMcLay & R.L.Barrett is also described as a new genus for theHibiscus panduriformisclade, which is allied toAbelmoschus. Finally, we introduce a new classification for the tribe and clarify the boundaries ofHibiscusandPavonia. 

Abstract PremiseTo date, phylogenetic relationships within the monogeneric Brunelliaceae have been based on morphological evidence, which does not provide sufficient phylogenetic resolution. Here we use target‐enriched nuclear data to improve our understanding of phylogenetic relationships in the family. MethodsWe used the Angiosperms353 toolkit for targeted recovery of exonic regions and supercontigs (exons + introns) from low copy nuclear genes from 53 of 70 species inBrunellia, and several outgroup taxa. We removed loci that indicated biased inference of relationships and applied concatenated and coalescent methods to inferBrunelliaphylogeny. We identified conflicts among gene trees that may reflect hybridization or incomplete lineage sorting events and assessed their impact on phylogenetic inference. Finally, we performed ancestral‐state reconstructions of morphological traits and assessed the homology of character states used to define sections and subsections inBrunellia. ResultsBrunelliacomprises two major clades and several subclades. Most of these clades/subclades do not correspond to previous infrageneric taxa. There is high topological incongruence among the subclades across analyses. ConclusionsPhylogenetic reconstructions point to rapid species diversification in Brunelliaceae, reflected in very short branches between successive species splits. The removal of putatively biased loci slightly improves phylogenetic support for individual clades. Reticulate evolution due to hybridization and/or incomplete lineage sorting likely both contribute to gene‐tree discordance. Morphological characters used to define taxa in current classification schemes are homoplastic in the ancestral character‐state reconstructions. While target enrichment data allows us to broaden our understanding of diversification inBrunellia, the relationships among subclades remain incompletely understood.