Single-locus molecular barcoding is a useful method for identifying overlooked and undescribed biodiversity, providing the groundwork for further systematic study and taxonomic investigation. A variety of methods for delimiting species from barcoding libraries have been developed and applied, allowing for rapid estimates of species diversity in a broad range of taxa. However, tree-based and distance-based analyses can infer different group assignments, potentially over- or underestimating the number of putative species groups. Here, we explore diversity of mainland species of anole lizards from the Chortís Block biogeographical province of northern Central America using a DNA barcoding approach, generating and analyzing cytochrome oxidase subunit I (COI) sequences for over 400 samples assignable to 33 of 38 (86.8%) native and one introduced mainland species. We subsequently tested the effects different models of nucleotide substitution, different species-delimitation algorithms, and reducing our dataset had on species delimitation estimates. We performed of two distance-based (ABGD, RESL) and three tree-based (bPTP, mPTP, GMYC) analyses on both the full dataset and a dataset consisting only of unique halotypes. From 34 nominal taxa, analyses of the full dataset recovered between 34 and 64 operational taxonomic units (OTUs), while analyses of the reduced dataset inferred between 36 and 59. Reassigning individuals to either mPTP-inferred or ABGD clustered (7.2% threshold) groups improved the detection of a barcoding gap across three different models of nucleotide substitution, removing overlap between intra- and interspecific distances. Our results highlight the underestimated diversity of mainland Chortís Block anoles, but the lack of congruence between analyses demonstrates the importance of considering multiple analytical methods when dealing with single-locus datasets. We recommend future studies consider the effects of different models of nucleotide substitution on proposed barcoding gaps, as well as the effect reducing a dataset to unique haplotypes may have on proposed diversity estimates.

No abstract

A distinctive new species of Typhlops is described from Parque Nacional Montaña de Santa Bárbara, 1550 m elevation, Departamento de Santa Bárbara, Honduras. The holotype and only known specimen of this new taxon is the largest specimen of the genus thus far reported from Mexico and Central America, and is further differentiated from all other Mesoamerican Typhlops by having 22-22-22 scales around the body and by having a dark brownish gray dorsum with a well-defined pale yellowish gray to immaculate white ventral coloration. This species is a member of the Caribbean Arc Group of Typhlops. An updated key to the Typhlopidae of Mesoamerica is provided. ResumenSe describe una nueva distintiva especie de Typhlops procedente del Parque Nacional Montaña de Santa Bárbara a 1550 m de elevación en el Departamento de Santa Bárbara, Honduras. El holotipo y único espécimen conocido de este nuevo taxón es el espécimen más grande del género reportado hasta ahora para México y Centro América. Adicionalmente, se diferencia de las demás Typhlops de Mesoamérica por tener 22-22-22 escamas alrededor del cuerpo y por tener el dorso de color gris pardusco con un patrón ventral bien definido de color gris amarillento pálido a blanco inmaculado. Esta especie es un miembro del grupo de Typhlops del Arco Caribeño. Se proporciona una clave nueva para las serpientes Typhlopidae de Mesoamerica.

No abstract