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Summary A new species ofTriolena,endemic to Colón Province, Panama, is described and illustrated. The specimens of this taxon were previously identified asTriolena lanceolata, but closer inspection has shown them to be morphologically and geographically distinct.Triolena anisophyllaK.Samra & Michelang. grows on rocks and tree trunks along rivers in Colón Province. This species is distinguishable by its strongly anisophyllous leaves and unique trichomes on the adaxial surface of the leaves. A complete description, distribution map, preliminary conservation assessment, taxonomic notes, and regional key are provided. 

ABSTRACT Anisophylly is a peculiar leaf trait in some opposite‐leaved taxa where opposing leaves are distinctly unequal. This study uses an expert‐curated specimen dataset to explore relationships of canopy cover and climate with the presence and intraspecific variation of anisophylly in the genusTriolena.Canopy and climate conditions are investigated between species and within a single species through beta regression models. No relationship was found between canopy cover and anisophylly. However, anisophylly is associated with conditions of high precipitation and high isothermality, which is evident acrossTriolenaand within a single species. In addition, partitioned ecoregion analyses illustrate that different types of anisophyllous leaf states occur in distinct ranges of precipitation and isothermality. Results suggest that anisophylly is associated with climate inTriolena. 

Abstract The Greater Antilles are renowned as a biodiversity hotspot and known to be geologically complex, which has led, in part, to the generation of organismal diversity in this area. One of the most species-rich montane groups within the Greater Antilles is the tribe Miconieae (Miconia s.l.) of the Melastomataceae, with ca. 325 species found there. The most diverse clade of Miconia in the Caribbean, the Caribbean clade, composes roughly half of that diversity, with an estimated 160 species, nearly all of which are endemic to the Greater Antilles. It is unclear how that diversity has been generated through time or where it originated, but we now have sufficiently well-sampled and robust datasets to test these patterns. Using a custom-built plastome dataset, we generated a robust phylogenetic hypothesis for 106 of the 160 Caribbean clade members and tested biogeographical patterns among the islands. Our results suggest that the Caribbean clade originated in the mid-Miocene, probably from a South American ancestor, and diversified substantially on the island of Cuba before repeatedly dispersing across other parts of the Greater Antilles, especially into nearby Hispaniola and then, to a lesser extent, into Jamaica, Puerto Rico and, finally, into the Lesser Antilles.