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Phylogenomics enhances our understanding of plant radiations in the biodiverse Andes. Our study focuses on Puya, primarily Andean and a part of the Bromeliaceae family. Using a phylogenomic framework based on the Angiosperms353 probe set for 80 species, we explored Puya′s phenotypic evolution and biogeography. Divergence time analyses and ancestral area estimations suggested that Puya originated in Central Coastal Chile around 9 million years ago (Ma). Subsequently, it dispersed to the dry valleys of the Central Andes and Puna regions between 5–8 Ma, leading to the emergence of major lineages. Key events in the last 2–4 million years include the recolonization of Chilean lowlands and dispersal to the northern Andes via Peru's Jalcas, facilitating passage through the Huancabamba depression. This event gave rise to the high‐elevation Northern Andes clade. Using phylogenetic comparative methods, we tested the hypothesis that adaptation to the Andes' island‐like high‐elevation ecosystems was facilitated by unique leaf and floral traits, life history, and inflorescence morphology. Our findings suggest correlations between inflorescence axis compression, protective bract overlap, and high‐elevation living, potentially preventing reproductive structure freezing. Semelparity evolved exclusively at high elevations, although its precise adaptive value remains uncertain. Our framework offers insights into Andean evolution, highlighting that lineages adapted to life in dry ecosystems can easily transition to high‐elevation biomes. It also underscores how the island‐like nature of high‐elevation ecosystems influences phenotypic evolution rates. Moreover, it opens avenues to explore genetic mechanisms underlying adaptation to extreme mountain conditions. [ABSTRACT FROM AUTHOR]

Puya pendula, a new species from rocky outcrops at mid elevations of the Eastern Cordillera of Colombia is described here. This new species is unique within Puya because of its rupicolous habit, pendulous inflorescence, glabrescent floral bracts, pedicels and sepals covered with glandular hairs, and white petals with a green central longitudinal stripe. The description is complemented with comments on the geographical distribution of the species, habitat, conservation status and a complete taxonomic discussion of its affinities within Puya. [ABSTRACT FROM AUTHOR]

The Ronnbergia alliance is a lineage of two genera, Ronnbergia and Wittmackia , which diversified in three centres of distribution; the Pacific Forest, the Atlantic Forest and the Caribbean. In this study, we reconstructed the most plausible biogeographic scenario that explain the disjunct evolution of the Ronnbergia alliance in these centres of diversity. We also compared the evolutionary rate dynamics of lineage diversification and floral evolution in each of these areas. Our results suggested that the Ronnbergia alliance originated in the Atlantic Forest c. 5.2 Mya. Ronnbergia originated c. 3.5 Mya after a long-distance dispersal event to the Pacific Forest. The diversification of Wittmackia started in the Atlantic Forest, c. 3.2 Mya, and experienced more heterogeneous evolutionary rate dynamics than Ronnbergia during its radiation. In Wittmackia a long-distance dispersal from the Atlantic Forest to Jamaica gave rise to the Caribbean clade, which diversified rapidly and experienced significantly higher rates of floral evolution. This study helped in understanding how bromeliad diversification occurs differently among major centres of biodiversity. In our case, we found how the Caribbean is a much more dynamic area of diversification than the Atlantic Forest or the Pacific Forest. [ABSTRACT FROM AUTHOR]

La distribución de la diversidad de Bromeliaceae en el Neotrópico es heterogénea, ya que la mayoría de las especies se concentran en hotspots de biodiversidad. Estudios filogenéticos han mostrado que los linajes que diversificaron en estas áreas muestran las tasas más altas de diversificación en toda la familia, las cuales probablemente son el reflejo de la evolución del hábito epífito acoplado con el reciente levantamiento de cordilleras. En este estudio presentamos el caso de la Alianza Ronnbergia, un linaje que diversificó en tres hotspots de diversidad: el noroccidente de Suramérica, la Mata Atlántica y el Caribe. Los resultados indican que hubo un evento vicariante que separó los linajes del noroccidente de Suramérica (=Ronnbergia) y la Mata Atlántica (=Wittmackia) hace 3.6 mya. Los linajes de Wittmackia que diversificaron en la Mata Atlántica experimentaron varios episodios de aceleración y desaceleración en las tasas de especiación que coinciden con las principales glaciaciones del pleistoceno. En estos linajes, sin embargo, las tasas de evolución floral se mantuvieron constantes y no hubo una variación fenotípica significativa. En la radiación de Wittmackia, dentro de la Mata Atlántica, un evento de dispersión a larga distancia desde Brasil hacia Jamaica dio origen a un linaje endémico del Caribe. Este linaje experimentó una aceleración significativa en las tasas de especiación y evolución floral, especialmente de estructuras relacionadas con protección contra herbívoros en especies que diversificaron en ambientes kársticos. Por otro lado, en la radiación de Ronnbergia en el noroccidente de Suramérica, las tasas de especiación y evolución floral fueron constantes, aunque la diversidad fenotípica floral es más alta que en Wittmackia, probablemente por la mayor diversidad de polinizadores presentes en esta región. Esta evidencia muestra la conexión y diferencias en las dinámicas evolutivas que dieron origen y mantienen la diversidad de linajes endémicos en los hotspots de diversidad. [ABSTRACT FROM AUTHOR]