ABSTRACT

The Caribbean Island Biodiversity Hotspot is composed primarily of the Bahamas and Greater and Lesser Antilles. A total of 180 genera (727 spp., ca. 9% of the species endemic to the Antilles) are restricted to this hotspot. Most of these genera are unispecific (51%), a pattern that is also found on other islands of the world. The majority of the endemic genera belong to the “Core Eudicot” clade, and they were published in two time periods (1854–1878 and 1904–1928). There are molecular phylogenies available for 63 of the endemic genera. However, phylogenetic reconstructions of only 21 genera are based on more than one independent DNA region and have well-supported clades and good taxonomic sampling. Six of the endemic genera form part of early-branching groups. We could not infer biogeographical conclusions from the molecular phylogenies of most of the endemic genera (43: 68%). There is an urgent need for (1) additional field studies to learn the conservation status of these genera, (2) effective protection of the habitats where the most endangered genera occur, and (3) additional biological and systematic studies of the least understood genera.

ABSTRACT

Proteaceae are restricted to the Southern Hemisphere, and of the seven tribes of the subfamily Grevilleoideae, only three (Macadamieae, Oriteae, and Embothrieae) have living members in Argentina. Megafossil genera of Proteaceae recorded from Patagonia include Lomatia, Embothrium, Orites, and Roupala. In this report, we evaluate and revise fossil Argentine Proteaceae on the basis of type material and new specimens. The new collections come from the Tufolitas Laguna del Hunco (early Eocene, Chubut Province), the Ventana (middle Eocene, Río Negro Province), and the Río Ñirihuau (late Oligocene-early Miocene, Río Negro Province) formations, Patagonia, Argentina. We confirm the presence of Lomatia preferruginea Berry, L. occidentalis (Berry) Frenguelli, L. patagonica Frenguelli, Roupala patagonica Durango de Cabrera et Romero, and Orites bivascularis Romero, Dibbern et Gandolfo. Fossils assigned to Embothrium precoccineum Berry and E. pregrandiflorum Berry are doubtful, and new material is necessary to confirm the presence of this genus in the fossil record of Patagonia. A putative new fossil species of Proteaceae is presented as Proteaceae gen. et sp. indet. Fossil Proteaceae are compared with modern genera, and an identification key for the fossil leaf species is presented. Doubtful historical records of Proteaceae fossils for the Antarctic Peninsula region and Patagonia are also discussed. Based on this revision, the three tribes of Proteaceae found today in Argentina were already present in Patagonia by the early Eocene, where they probably arrived via the Australia-Antarctica-South America connection.

RESUMEN

La familia Proteaceae está restringida al Hemisferio Sur, y en Argentina sólo tres (Macadamieae, Oriteae y Embothrieae) de las siete tribus de la subfamilia Grevilleoideae están representadas. En Patagonia, megafósiles asignados a Proteaceae incluyen los géneros Lomatia, Embothrium, Orites y Roupala. En este trabajo, se evalúan y revisan todos los registros fósiles de Proteaceae para Argentina basados en el material tipo y en nuevos especímenes. Las nuevas colecciones fueron realizadas en las formaciones Tufolitas Laguna del Hunco (Eoceno Temprano, Provincia del Chubut), Ventana (Eoceno Medio, Provincia de Río Negro) y Río Ñirihuau (Oligoceno Tardío-Mioceno Temprano, Provincia de Río Negro), Patagonia, Argentina. Se confirma la presencia de Lomatia preferruginea Berry, L. occidentalis (Berry) Frenguelli, L. patagonica Frenguelli, Roupala patagonica Durango de Cabrera et Romero, and Orites bivascularis Romero, Dibbern et Gandolfo. Los fósiles asignados a Embothrium precoccineum Berry and E. pregrandiflorum Berry son dudosos, y nuevo material es necesario para confirmar la presencia de este género en el registro fósil de Patagonia. Una posible nueva especie fósil es presentada como Proteaceae gen. et sp. indet. Los fósiles asignados a Proteaceae son comparados con géneros modernos, y se proporciona una clave para la identificación de las especies fósiles. Los registros fósiles históricos dudosos de Proteaceae para la región de la Península Antártica y Patagonia s