Begonia ludwigii y B. parcifolia (Begoniaceae) dos registros nuevos para la flora peruana / Begonia ludwigii and B. parcifolia (Begoniaceae) two new records to the Peruvian flora

Begonia ludwigii Irmscher y B. parcifolia C. DC. se registran para la flora peruana, donde ocurren dentro de la zona biodiversa Amotape-Huancabamba. Ambas especies fueron originalmente consideradas como endémicas de Ecuador. Dentro de Perú, B. ludwigii es reportada de cuatro poblaciones en los Departamentos de Piura, Lambayeque y Cajamarca, mientras que B. parcifolia es reportada de tres poblaciones en los Departamentos de Tumbes, Piura y Cajamarca. Se proporcionan descripciones de B. ludwigii y B. parcifolia y se mapean y discuten sus distribuciones. También se presenta información sobre su taxonomía y estado de conservación.

Begonia ludwigii Irmscher and B. parcifolia C. DC. are newly recorded for the Peruvian flora, where they occur within the biodiverse Amotape-Huancabamba zone. Both species were originally considered to be endemic to Ecuador. Within Peru, B. ludwigii is reported from four populations in the Departments of Piura, Lambayeque and Cajamarca, while B. parcifolia is reported from three populations in the Departments of Tumbes, Piura and Cajamarca. Descriptions of B. ludwigii and B. parcifolia are provided and their distributions mapped and discussed. Information about their taxonomy and conservation status are also presented.

Phylogenetic position and biogeography of Hillebrandia sandwicensis (Begoniaceae): a rare Hawaiian relict.

The Begoniaceae consist of two genera, Begonia, with approximately 1400 species that are widely distributed in the tropics, and Hillebrandia, with one species that is endemic to the Hawaiian Islands and the only member of the family native to those islands. To help explain the history of Hillebrandia on the Hawaiian Archipelago, phylogenetic relationships of the Begoniaceae and the Cucurbitales were inferred using sequence data from 18S, rbcL, and ITS, and the minimal age of both Begonia and the Begoniaceae were indirectly estimated. The analyses strongly support the placement of Hillebrandia as the sister group to the rest of the Begoniaceae and indicate that the Hillebrandia lineage is at least 51-65 million years old, an age that predates the current Hawaiian Islands by about 20 million years. Evidence that Hillebrandia sandwicensis has survived on the Hawaiian Archipelago by island hopping from older, now denuded islands to younger, more mountainous islands is presented. Various scenarios for the origin of ancestor to Hillebrandia are considered. The geographic origin of source populations unfortunately remains obscure; however, we suggest a boreotropic or a Malesian-Pacific origin is most likely. Hillebrandia represents the first example in the well-studied Hawaiian flora of a relict genus.