2016-12-23T18:52:10

To facilitate biological study we define “Caribbean Islands” as a biogeographic region that includes the Antilles, the Bahamas, and islands bordering Central and South America separated from mainland areas by at least 20 meters of water depth. The advantages of this definition are that it captures nearly all islands with endemic species and with at least some Antillean-derived species, and still circumscribes a region of high biodiversity and biogeographic significance. We argue that Caribbean islands, in this expanded sense, are also cohesive from a conservation standpoint in that they share high human population densities and similar conservation threats. A disadvantage of this definition, strictly applied, is that it includes some islands (e.g., Trinidad) that have mostly mainland species. However, we propose that researchers can increase the stringency of the definition so that it is less inclusive, and make comparisons between different definitions as needed. We provide an updated checklist with standardized common English names for the 1,013 species of amphibians and reptiles occurring in the region, along with principles for constructing common names.

Historical Background. 1 What Are Homalopsid Snakes?. Generic Designations, Why So Many Genera?. Homalopsidae Incertae Sedis. Common Names and Photographs. Methods. Accounts for Genera and Species.

No abstract

In this study, we analyse New World coral snakes in a phylogenetic framework based upon an increased molecular data set, including novel sequences for the only two sympatric species known from an island (Trinidad, West Indies). Their presence in Trinidad and absence in Tobago offers a unique system to study the phylogeography of the region. We assess the tempo and mode of colonisation of Micrurus on the island, in addition to discussing the phylogenetic relationships for the genus Micrurus concerning two phenotypic traits, body and tail banding patterns. These relationships are analysed for the first time on statistical coalescent phylogeographic discrete ancestral reconstruction. We find a robust phylogenetic component in these characteristics, where strongly supported clades are recovered: prior to the onset of the Early Miocene, a triadal and tricolour tail clade composed of species from South America, and a second clade dating to the Middle‐Late‐ Miocene with monadal and bicolour tails widely distributed from North to South America. The divergence between clades dates to the Oligocene and suggests an ancient pre‐isthmus divergence supporting the arrival of the triadal clade into South America, before the connection between Central and South America was established. We find the two coral snakes present in the West Indies, M. diutius and M. circinalis, belong to the triadal and monadal clades, respectively. Guyana and Trinidad Micrurus diutius share the same haplotypes suggesting a Late Pleistocene–Holocene vicariance when sea level rises separated Trinidad from the mainland. A second lineage of diutius‐like snakes is present in Guyana and is confirmed as M. lemniscatus which is assigned as a voucher and restricts the type locality for M. lemniscatus.