New fossils shed light on the Late Cretaceous terrestrial community in the Caribbean and the First American Biotic Interchange

Abstract

The Caribbean islands are one of the most important hotspots of endemism and biodiversity globally, and the scenario of unique examples of biological radiations. Although our knowledge of the current and recently extinct diversity in the area is strong, the origin and evolution of most groups in the region remain obscure because of the absence of fossils from deep time periods. The existence of temporal islands on the Caribbean plate can be traced back to the late Mesozoic, but little evidence of the paleo-communities that once inhabited the archipelago and their relationship with the older lineages in the region has been discovered. Simultaneously, the relationship of the early Caribbean archipelago with the Late Cretaceous–early Paleogene biotic interchange between the Americas has remained unsolved. Here we describe the first evidence of a Late Cretaceous terrestrial community in the region based on several remains recovered at three upper Campanian–lower Maastrichtian localities in Central Cuba. The fossil assemblage includes four specimens referable to a midsize pterosaur on the base of morphological and paleohistological characters, as well as seeds and casts of leafy shoots of plants of the families Cupressaceae and Lauraceae. Fossils fruits of a new taxon closely related to Chlorocardium are of particular interest because they correspond to the first direct evidence of the role played by the Caribbean seaway and islands in the First American Biotic Interchange.