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The Jamaican boa (Epicrates subflavus; also called Yellow boa) is an endemic species whose natural populations greatly and constantly declined since the late 19th century, mainly because of predation by introduced species, human persecution, and habitat destruction. In-situ conservation of the Jamaican boa is seriously hindered by the lack of information on demographic and ecological parameters as well as by a poor understanding of the population structure and species distribution in the wild. Here, using nine nuclear microsatellite loci and a fragment of the mitochondrial cytochrome b gene from 87 wild-born individuals, we present the first molecular genetic analyses focusing on the diversity and structure of the natural populations of the Jamaican boa. A model-based clustering analysis of multilocus microsatellite genotypes identifies three groups that are also significantly differentiated on the basis of F-statistics. Similarly, haplotypic network reconstruction methods applied on the cytochrome b haplotypes isolated here identify two well-differentiated haplogroups separated by four to six fixed mutations. Bayesian and metaGA analyses of the mitochondrial data set combined with sequences from other Boidae species indicate that rooting of the haplotypic network occurs most likely between the two defined haplogroups. Both analyses (based on nuclear and mitochondrial markers) underline an Eastern vs. (Western + Central) pattern of differentiation in agreement with geological data and patterns of differentiation uncovered in other vertebrate and invertebrate Jamaican species. Our results provide important insights for improving management of ex-situ captive populations and for guiding the development of proper in-situ species survival and habitat management plans for this spectacular, yet poorly known and vulnerable, snake.

Despite the attention given to them, the Galápagos have not yet finished offering evolutionary novelties. When Darwin visited the Galápagos, he observed both marine (Amblyrhynchus) and land (Conolophus) iguanas but did not encounter a rare pink blackstriped land iguana (herein referred to as ''rosada,'' meaning ''pink'' in Spanish), which, surprisingly, remained unseen until 1986. Here, we show that substantial genetic isolation exists between the rosada and syntopic yellow forms and that the rosada is basal to extant taxonomically recognized Galápagos land iguanas. The rosada, whose present distribution is a conundrum, is a relict lineage whose origin dates back to a period when at least some of the present-day islands had not yet formed. So far, this species is the only evidence of ancient diversification along the Galápagos land iguana lineage and documents one of the oldest events of divergence ever recorded in the Galápagos. Conservation efforts are needed to prevent this form, identified by us as a good species, from extinction.genetic isolation ͉ molecular phylogeny ͉ evolution ͉ islands ͉ lizards S ince Darwin's pioneering work in the archipelago, the Galápagos Islands have been a major scientific resource for evolutionary biologists. This archipelago, currently consisting of about a dozen volcanic islands and more than 100 associated islets, is located on the equator, about 1,000 kilometers west of the South-American coast (Fig. 1). Given their volcanic origin, the Galápagos Islands host unique flora and fauna that have evolved over millions of years in geographic isolation, generating a variety of endemic species with unique and varied ecological, morphological, and behavioral adaptations (1, 2).Land iguanas are among the most spectacular representative species of the Galápagos Islands. They once lived in many areas of the Galápagos archipelago (Fig. 1). Currently, many factors contribute to their threatened status (3), one of which may be incomplete taxonomy (4). Two species of Galápagos land iguanas are currently recognized: Conolophus pallidus and Conolophus subcristatus, with the former occurring only on Santa Fe, whereas C. subcristatus occurs on Fernandina, Isabela, Santa Cruz, Plaza Sur, Seymour Norte (a translocated population), and Baltra.Charles Darwin visited the Galápagos in 1835. During the 5 weeks of his stay in the archipelago, he did not explore Volcan Wolf (the northernmost volcano in Isabela). Thus, although he noticed and commented on both marine and land iguanas (5), he did not encounter a distinct form of land iguana that occurs only on that volcano. Perhaps even more surprising, this form (herein referred to as ''rosada,'' † meaning ''pink'' in Spanish) remained unrecorded despite many other scientists having visited Volcan Wolf over the past century. Since it was accidentally seen by some Galápagos National Park rangers in 1986, this form has received no attention. The rosada form is characterized by a distinct phenotype (Fig. 2). It can be clearly distinguished from the syntopic...

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