Reassessing a Holocene extinction: multiple lines of evidence do not support the historical presence and recent extirpation of a protected anole on the island of Anguilla

Accurate assessment of historical species ranges is important for conservation science and management. Inaccurate historical species ranges can lead to incorrect assumptions about local extinctions, population trends, and potential sites for reintroductions. Yet, historical knowledge is often lacking for many species. Here, we present body size data on the case of the bearded anole, Anolis pogus, which is long believed to have been recently extirpated from the island of Anguilla. Body size data consists of snout-vent length for adult male and female Anolis pogus, A. schwartzi, and A. gingivinus. These data were generated from a mix of field measurements and samples from natural history collections. We then compared these data with the size distributions of anole fossils found on the island of Anguilla. We show that rather than a two-species community, the fossil size data better corresponds to sexual dimorphism in a single-species community consisting only of A. gingivinus. Thus, fossil data do not support the historical presence of A. pogus as previously suggested. We also generated WGS libraries from archival samples of Anolis pogus allegedly collected on Anguilla. We show that all of these museum samples are actually A. schwartzi and originated from a nearby island, St. Eustatius. Thus, there are no existing collections of A. pogus from the island of Anguilla. Scripts for analyzing these genomic data are archived on Zenodo. Raw sequence data are hosted on NCBI's SRA database.