TY - JOUR
T1 - Between a rock and a dry place
T2 - phylogenomics, biogeography, and systematics of ridge-tailed monitors (Squamata: Varanidae: Varanus acanthurus complex)
AU - Pavón-Vázquez, Carlos J.
AU - Esquerré, Damien
AU - Fitch, Alison J.
AU - Maryan, Brad
AU - Doughty, Paul
AU - Donnellan, Stephen C.
AU - Keogh, J. Scott
N1 - Publisher Copyright:
© 2022 Elsevier Inc.
PY - 2022/8
Y1 - 2022/8
N2 - Genomic data are a powerful tool for the elucidation of evolutionary patterns at the population level and above. The combined analysis of genomic and morphological data can result in species delimitation hypotheses that reflect evolutionary history better than traditional taxonomy or any individual source of evidence. Here, we used thousands of single nucleotide polymorphisms, mitochondrial sequences, and comprehensive morphological data to characterize the evolutionary history of the ridge-tailed monitors in the Varanus acanthurus complex (V. acanthurus, V. baritji, and V. storri), a group of saxicolous lizards with a wide distribution in Australia, the driest vegetated continent. We found substantial genetic structure in the group and identify nine geographically clustered populations. Based on admixture patterns and species delimitation analyses we propose a taxonomic scheme that differs from current taxonomy. We consider V. acanthurus as monotypic, synonymize V. baritji with V. a. insulanicus (as a redefined V. insulanicus), elevate the subspecies of V. storri to full species (V. storri and V. ocreatus), and describe a new species from a previously identified center of endemism. The relationships among the species remain unresolved, likely as a result of fast speciation. Our study highlights the capability of large datasets to illuminate admixture patterns, biogeographic history, and species limits, even when phylogeny is not completely resolved. Furthermore, our results highlight the impact that the Cenozoic aridification of Australia had on saxicolous taxa and the role of mesic rocky escarpments as refugia. These habitats apparently allowed the persistence of lineages that became sources of colonization for arid environments.
AB - Genomic data are a powerful tool for the elucidation of evolutionary patterns at the population level and above. The combined analysis of genomic and morphological data can result in species delimitation hypotheses that reflect evolutionary history better than traditional taxonomy or any individual source of evidence. Here, we used thousands of single nucleotide polymorphisms, mitochondrial sequences, and comprehensive morphological data to characterize the evolutionary history of the ridge-tailed monitors in the Varanus acanthurus complex (V. acanthurus, V. baritji, and V. storri), a group of saxicolous lizards with a wide distribution in Australia, the driest vegetated continent. We found substantial genetic structure in the group and identify nine geographically clustered populations. Based on admixture patterns and species delimitation analyses we propose a taxonomic scheme that differs from current taxonomy. We consider V. acanthurus as monotypic, synonymize V. baritji with V. a. insulanicus (as a redefined V. insulanicus), elevate the subspecies of V. storri to full species (V. storri and V. ocreatus), and describe a new species from a previously identified center of endemism. The relationships among the species remain unresolved, likely as a result of fast speciation. Our study highlights the capability of large datasets to illuminate admixture patterns, biogeographic history, and species limits, even when phylogeny is not completely resolved. Furthermore, our results highlight the impact that the Cenozoic aridification of Australia had on saxicolous taxa and the role of mesic rocky escarpments as refugia. These habitats apparently allowed the persistence of lineages that became sources of colonization for arid environments.
KW - Aridification
KW - Australia
KW - Morphometrics
KW - Phylogeography
KW - Refugia
KW - Species delimitation
UR - http://www.scopus.com/inward/record.url?scp=85131902924&partnerID=8YFLogxK
U2 - 10.1016/j.ympev.2022.107516
DO - 10.1016/j.ympev.2022.107516
M3 - Article
SN - 1055-7903
VL - 173
JO - Molecular Phylogenetics and Evolution
JF - Molecular Phylogenetics and Evolution
M1 - 107516
ER -