Determining whether a conflict between gene trees and species trees represents incomplete lineage sorting (ILS) or hybridization involving native and/or invasive species has implications for reconstructing evolutionary relationships and guiding conservation decisions. Among vertebrates, turtles represent an exceptional case for exploring these issues because of the propensity for even distantly related lineages to hybridize. In this study we investigate a group of freshwater turtles (Trachemys) from a part of its range (the Greater Antilles) where it is purported to have undergone reticulation events from both natural and anthropogenic processes. We sequenced mtDNA for 83 samples, sequenced three nuDNA markers for 45 samples, and cloned 29 polymorphic sequences, to identify species boundaries, hybridization, and intergrade zones for Antillean Trachemys and nearby mainland populations. Initial coalescent analyses of phased nuclear alleles (using (*)BEAST) recovered a Bayesian species tree that strongly conflicted with the mtDNA phylogeny and traditional taxonomy, and appeared to be confounded by hybridization. Therefore, we undertook exploratory phylogenetic analyses of mismatched alleles from the "coestimated" gene trees (Heled and Drummond, 2010) in order to identify potential hybrid origins. The geography, morphology, and sampling context of most samples with potential introgressed alleles suggest hybridization over ILS. We identify contact zones between different species on Jamaica (T. decussata × T. terrapen), on Hispaniola (T. decorata × T. stejnegeri), and in Central America (T. emolli × T. venusta). We are unable to determine whether the distribution of T. decussata on Jamaica is natural or the result of prehistoric introduction by Native Americans. This uncertainty means that the conservation status of the Jamaican T. decussata populations and contact zone with T. terrapen are unresolved. Human-mediated dispersal events were more conclusively implicated for the prehistoric translocation of T. stejnegeri between Puerto Rico and Hispaniola, as well as the more recent genetic pollution of native species by an invasive pet turtle native to the USA (T. scripta elegans). Finally, we test the impact of introgressed alleles using the multispecies coalescent in a Bayesian framework and show that studies that do not phase heterozygote sequences of hybrid individuals may recover the correct species tree, but overall support for clades that include hybrid individuals may be reduced.

No abstract

Hispaniolan hylid frogs are represented by four endemic species: Hypsiboas heilprini, Osteopilus dominicensis, O. pulchrilineatus and O. vastus. There are two tadpole ecomorphs represented in the hylid frogs of Hispaniola: lentic (O. dominicensis and O. pulchrilineatus) and lotic (H. heilprini and O. vastus). Tadpoles of the four species may be found sympatrically, but in different microhabitats. Hispaniolan hylid tadpoles reach a moderate size (up to 57 mm in total length is recorded in H. heilprini), and differ from those of Peltophryne, Rhinella, Leptodactylus and Lithobates (the other genera with free-living larvae present on the island), by having the oral discs not emarginated and, from the first three taxa, by a dextral vent opening. Oral deformities observed in most tadpoles of H. heilprini from Ébano Verde, Cordillera Central, were caused by the chytrid fungus Batrachochytrium dendrobatidis. An identification key is also provided.

A new species of frog, Eleutherodactylus geitonos sp. nov., is described from the southeastern slope of the Cordillera Central, Dominican Republic. The new frog is closely related to E. haitianus and both species share a small size. They differ in some morphological proportions and other external features, coloration, advertisement calls and DNA sequences of the 16S rRNA gene. Morphological and bioacoustic comparisons with other species in the  E. abbotti species group are also provided. Our preliminary genetic data suggest that the taxonomic status of E. neodreptus (a synonym of E. audanti) and E. melatrigonum need to be re-evaluated.

Se realizó un inventario de los reptiles presentes en el área protegida y refugio de vida silvestre El Cañón del río Gurabo o Furnia de Gurabo, localizada al suroeste del municipio de Mao, provincia Valverde, República Dominicana. Se registran 15 especies para la zona, agrupadas en 10 familias y 12 géneros. Se amplía la distribución del gecko gigante de la Hispaniola, Aristelliger lar.