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Because the generic name Elliotia proposed by us (Stiles et al. 2017a) was found to be preoccupied, we herein rename this genus, including a detailed diagnosis; the generic circumscription and type species remain unchanged. This change does not affect the generic reorganization of the Trochilini presented by Stiles et al. (2017a).

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The generic nomenclature of the hummingbirds is unusually complicated. McGuire et al.'s (2014) recent phylogeny of the Trochilidae based on DNA sequence data has greatly clarified relationships within the family but conflicts strongly with the traditional classification of the family at the genus level, especially that of the largest and most recently derived clade, the Trochilini or "emeralds". We recently presented a historical review of this classification and the generic modifications required by the Code of the International Commission on Zoological Nomenclature. Herein we present a revised generic classification of the Trochilini based upon McGuire et al.'s genetic data, while producing diagnosable generic groupings and preserving nomenclatural stability insofar as possible. However, this generic rearrangement has necessitated the resurrection of nine generic names currently considered synonyms, the synonymization of seven currently recognized genera and the creation of one new genus. The generic changes we recommend to the classification are drastic, and we summarize these in tabular form in comparison with the three most recent classifications of the Trochilini. Where appropriate, we outline alternatives to our proposed arrangement. The classification treats 110 species in 35 genera, including two species that remain unplaced for lack of genetic samples.

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The generic classification of the Trochilidae is unusually complicated because early authors, faced with a deluge of specimens with little or no data, often based species and genus names on superficial plumage characters derived from figured plates of varying artistic quality and reproduction. Working independently and with little knowledge of species distributions and with the fixation of type species for genera inconsistent or ignored, these authors produced a bewildering array of generic synonyms. The generic nomenclature of the largest and most recently derived clade of hummingbirds, the tribe Trochilini or "emeralds", presents an unusually tangled web. Here we review the history of hummingbird generic nomenclature from Linnaeus to the present, giving detailed attention to two generic names that epitomize this confusion: Amazilia (the variety of spellings, supposed type species and circumscriptions makes for an especially complicated tangle) and Leucippus (for which nearly every successive author has advocated a different circumscription). Through application of the International Code for Zoological Nomenclature, this review lays the foundation for a revision of the generic nomenclature of the emeralds to bring it into conformity with recent genetic studies elucidating the phylogeny of this clade.

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The tempo of species diversification in large clades can reveal fundamental evolutionary mechanisms that operate on large temporal and spatial scales. Hummingbirds have radiated into a diverse assemblage of specialized nectarivores comprising 338 species, but their evolutionary history has not, until now, been comprehensively explored. We studied hummingbird diversification by estimating a time-calibrated phylogeny for 284 hummingbird species, demonstrating that hummingbirds invaded South America by ∼22 million years ago, and subsequently diversified into nine principal clades (see [5-7]). Using ancestral state reconstruction and diversification analyses, we (1) estimate the age of the crown-group hummingbird assemblage, (2) investigate the timing and patterns of lineage accumulation for hummingbirds overall and regionally, and (3) evaluate the role of Andean uplift in hummingbird speciation. Detailed analyses reveal disparate clade-specific processes that allowed for ongoing species diversification. One factor was significant variation among clades in diversification rates. For example, the nine principal clades of hummingbirds exhibit ∼15-fold variation in net diversification rates, with evidence for accelerated speciation of a clade that includes the Bee, Emerald, and Mountain Gem groups of hummingbirds. A second factor was colonization of key geographic regions, which opened up new ecological niches. For example, some clades diversified in the context of the uplift of the Andes Mountains, whereas others were affected by the formation of the Panamanian land bridge. Finally, although species accumulation is slowing in all groups of hummingbirds, several major clades maintain rapid rates of diversification on par with classical examples of rapid adaptive radiation.

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