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From the recently discovered Montbrook locality, Levy County, Florida (late Miocene; late Hemphillian land mammal age), a complete coracoid and nearly complete scapula represent a large heron that we name Taphophoyx hodgei new genus and species. While the phylogenetic affinities of T. hodgei are not well resolved, the tiger-herons Tigrisoma spp. or boat-billed heron Cochlearius cochlearius (both Neotropical) may be the closest living relative(s) of Taphophoyx, based in large part on several shared characters of the facies articularis clavicularis and facies articularis humeralis. Nevertheless, the coracoid of Taphophoyx has a uniquely prominent facies articularis humeralis and a uniquely sterno-ventral surface of corpus coracoidei. All 21 taxa of birds recorded thus far from Montbrook (mostly aquatic forms such as swans, ducks, geese, grebes, cormorants, ibises, sandpipers, etc.) probably represent extinct species, although Taphophoyx hodgei is the only one assigned to an extinct genus.
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Population genetic structure and species delimitation of a widespread, Neotropical dwarf gecko, Gonatodes humeralis (Sphaerodactylidae: Gekkota)
Amazonia harbors the greatest biological diversity on Earth. One trend that spans Amazonian taxa is that most taxonomic groups either exhibit broad geographic ranges or small restricted ranges. This is likely because many traits that determine a species range size, such as dispersal ability or body size, are autocorrelated. As such, it is rare to find groups that exhibit both large and small ranges. Once identified, however, these groups provide a powerful system for isolating specific traits that influence species distributions. One group of terrestrial vertebrates, gecko lizards, tends to exhibit small geographic ranges. Despite one exception, this applies to the Neotropical dwarf geckos of the genus Gonatodes. This exception, Gonatodes humeralis, has a geographic distribution almost 1,000,000 km2 larger than the combined ranges of its 30 congeners. As the smallest member of its genus and a gecko lizard more generally, G. humeralis is an unlikely candidate to be a wide-ranged Amazonian taxon. To test whether or not G. humeralis is one or more species, we generated molecular genetic data using restriction-site associated sequencing (RADseq) and traditional Sanger methods for samples from across its range and conducted a phylogeographic study. We conclude that G. humeralis is, in fact, a single species across its contiguous range in South America. Thus, Gonatodes is a unique clade among Neotropical taxa, containing both wide-ranged and range-restricted taxa, which provides empiricists with a powerful model system to correlate complex species traits and distributions. Additionally, we provide evidence to support species-level divergence of the allopatric population from Trinidad and we resurrect the name Gonatodes ferrugineus from synonymy for this population.
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- Award ID(s):
- 1657662
- PAR ID:
- 10149219
- Date Published:
- Journal Name:
- Molecular phylogenetics and evolution
- Volume:
- 133
- ISSN:
- 1095-9513
- Page Range / eLocation ID:
- 54–66
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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