Museomics illuminate the history of an extinct, paleoendemic plant lineage ( Hesperelaea , O leaceae) known from an 1875 collection from G uadalupe I sland, M exico

Museum collections are essential for understanding biodiversity and next‐generation sequencing methods ( NGS ) offer new opportunities to generate genomic data on specimens of extinct species for phylogenetic and other studies. Hesperelaea is a monotypic O leaceae genus that was collected only once, 140 years ago on G uadalupe I sland, M exico. This lineage is almost certainly extinct, and has been considered an insular paleoendemic of unknown relationship within subtribe Oleinae . Here, a genome skimming approach was attempted on the H. palmeri specimen to generate genomic data in order to interpret the biogeographic history of Hesperelaea in a phylogenetic framework. Despite highly degraded DNA , we obtained the complete plastome, the nuclear ribosomal DNA cluster ( nrDNA ), and partial sequences of low‐copy genes. Six plastid regions and nr DNA internal transcribed spacers were used for phylogenetic estimations of subtribe Oleinae , including data from previous studies. B ayesian and maximum likelihood phylogenies strongly place Hesperelaea within an A merican lineage that includes Forestiera and Priogymnanthus . Molecular dating suggests an E arly M iocene divergence between Hesperelaea and its closest relatives. Our study thus confirms that Hesperelaea was a paleoendemic lineage that likely predates G uadalupe I sland, and provides a notable example of the high potential of NGS for analyzing historical herbarium specimens and revolutionizing systematics. © 2015 The Linnean Society of London, Biological Journal of the Linnean Society , 2015, ●● , ●●–●●.