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1.
Aim The origins of the Cuban biota are of long‐standing interest in biogeography, and the source of a small live oak (Quercus series Virentes) population on Cuba remains unresolved. Based on morphological evidence, previous authors have hypothesized a Florida origin from either Q. geminata or Q. virginiana or both; a Mexican origin from Q. oleoides; or a hybrid origin from both sources. We use molecular data and taxonomically informative leaf morphology to identify the source species and timing of colonization. Location Cuba, Central America, Mexico and the south‐eastern United States. Methods  We collected representative samples of Cuban oaks and each putative source species and genotyped each sample at 12 nuclear microsatellites and two chloroplast DNA sequences. We estimated population structure using a Bayesian clustering analysis and F‐statistics, pairwise migration rates among taxa, and divergence time using an isolation‐with‐migration model. We measured seven leaf traits and conducted an analysis of similarity (ANOSIM) to determine which putative source species was most similar to Cuban oaks. Results Cuban oak contains one chloroplast DNA haplotype, which is common in southern Florida. Bayesian clustering analysis of microsatellites revealed that the Cuban oak forms a distinct and pure population cluster, and F‐statistics showed that Cuban oaks are differentiated least from Q. virginiana and most from Q. geminata. Migration rates were highest out of Cuba to Q. oleoides. Molecular diversity, the ratio of allelic richness to allele size range, and effective population size of the Cuban oak were relatively low, suggesting a founder effect. Divergence time estimates fell entirely within the Pleistocene (628–6 ka), considering a range of mutation rates and generation times. Cuban oaks were morphologically most similar to Q. virginiana and least similar to Q. geminata. Main conclusions Molecular and morphological data support a Pleistocene dispersal of Q. virginiana from Florida to Cuba, followed by isolation and divergence, then limited dispersal and introgression from Cuba to Q. oleoides in Central America. Birds could have dispersed acorns to Cuba during a glacial period when sea levels were low. These results highlight the varied origin of the Cuban biota and the possible role of Pleistocene glaciations in the establishment of temperate taxa in the tropics.  相似文献   

2.
There are a few baseline reef-systems available for understanding the microbiology of healthy coral reefs and their surrounding seawater. Here, we examined the seawater microbial ecology of 25 Northern Caribbean reefs varying in human impact and protection in Cuba and the Florida Keys, USA, by measuring nutrient concentrations, microbial abundances, and respiration rates as well as sequencing bacterial and archaeal amplicons and community functional genes. Overall, seawater microbial composition and biogeochemistry were influenced by reef location and hydrogeography. Seawater from the highly protected ‘crown jewel’ offshore reefs in Jardines de la Reina, Cuba had low concentrations of nutrients and organic carbon, abundant Prochlorococcus, and high microbial community alpha diversity. Seawater from the less protected system of Los Canarreos, Cuba had elevated microbial community beta-diversity whereas waters from the most impacted nearshore reefs in the Florida Keys contained high organic carbon and nitrogen concentrations and potential microbial functions characteristic of microbialized reefs. Each reef system had distinct microbial signatures and within this context, we propose that the protection and offshore nature of Jardines de la Reina may preserve the oligotrophic paradigm and the metabolic dependence of the community on primary production by picocyanobacteria.  相似文献   

3.
Synopsis Permit, Trachinotus falcatus are economically and ecologically important throughout their range of the Caribbean, subtropical and tropical western Atlantic, and Gulf of Mexico. Despite their economic importance, little is known about the biology and ecology of permit, and most existing information is from Florida. While sufficient information is available to paint a general picture of permit life history, details are lacking for most life stages. For the juvenile life stage, nursery habitats and size and age at settlement have not yet been defined. Although six distinct habitat types (medium energy and low energy windward beaches, leeward beaches, and windward, leeward, and lagoon interior mangrove shorelines) were sampled to determine spatial patterns of habitat use by early juvenile permit at Turneffe Atoll, Belize, Central America, and the Florida Keys, USA, 99% of juvenile permit were found along medium energy windward beaches, indicating their role as nursery habitat for this species. A sub-sample of juvenile permit from Florida was examined to estimate spawning date and age at settlement from otoliths. Size-frequency distributions and otolith age analysis indicate that larval duration is approximately 15 – 20 days, and settlement occurs year-round. Since permit in Florida spawn March through July, from March through September in Cuba, and from February through October in Belize, year-round settlement indicates population connectivity via larval transport. These results lay the foundation for future research on larval supply, population connectivity, and juvenile ecology, and will aid in the ongoing formulation of a conservation plan toward a sustainable fishery for permit.  相似文献   

4.
ABSTRACT We used nucleotide sequence data from a mitochondrial DNA fragment to characterize variation within the endangered Lower Keys marsh rabbit (Sylvilagus palustris hefneri). We observed 5 unique mitochondrial haplotypes across different sampling sites in the Lower Florida Keys, USA. Based on the frequency of these haplotypes at different geographic locations and relationships among haplotypes, we observed 2 distinct clades or groups of sampling sites (western and eastern clades). These 2 groups showed low levels of gene flow. Regardless of their origin, marsh rabbits from the Lower Florida Keys can be separated into 2 genetically distinct management units, which should be considered prior to implementation of translocations as a means of offsetting recent population declines.  相似文献   

5.
Taxonomic uncertainties within the genus Chondrohierax stem from the high degree of variation in bill size and plumage coloration throughout the geographic range of the single recognized species, hook-billed kite Chondrohierax uncinatus . These uncertainties impede conservation efforts as local populations have declined throughout much of its geographic range from the Neotropics in Central America to northern Argentina and Paraguay, including two island populations on Cuba and Grenada, and it is not known whether barriers to dispersal exist between any of these areas. Here, we present mitochondrial DNA (mtDNA; cytochrome B and NADH dehydrogenase subunit 2) phylogenetic analyses of Chondrohierax , with particular emphasis on the two island taxa (from Cuba, Chondrohierax uncinatus wilsonii and from Grenada, Chondrohierax uncinatus mirus ). The mtDNA phylogenetic results suggest that hook-billed kites on both islands are unique; however, the Cuban kite has much greater divergence estimates (1.8–2.0% corrected sequence divergence) when compared with the mainland populations than does the Grenada hook-billed kite (0.1–0.3%). Our findings support species status for the Cuban form, as Chondrohierax wilsonii , and subspecific status for the Grenada form. For mainland taxa, we do not find support for the currently recognized subspecies Chondrohierax uncinatus aquilonis in western Mexico, but we do find evidence for a genetic subdivision between populations in Central and South America, a difference previously unsuspected. The results of this study help identify conservation priorities associated with these unique Neotropical raptors. This information is of immediate interest because the Cuban kite has not been reliably seen since 1992, and <50 hook-billed kites currently inhabit Grenada.  相似文献   

6.
The eastern North American population of the monarch butterfly (Danaus plexippus plexippus) has different migratory routes. The majority fly to overwintering colonies in Mexico and others take an eastern route through Florida and Cuba. Monarchs migrating through Florida–Cuba do not overwinter and are mostly found nectaring and flying close to vegetation. This present study explores whether Florida–Cuba versus Mexican migrants differ in (1) phenotypic traits important for migration (e.g. wing size and condition, lipid and lean mass content, and reproductive status) and (2) migratory strategies. The monarch natal grounds (e.g. migrants versus residents) were determined through thin‐layer chromatography cardenolide fingerprint and stable isotopes (hydrogen δ2H and carbon δ13C). In addition, wing size and condition, lipid and lean mass, and reproductive status were determined. The results suggest that Mexican migrants are better suited for longer sustained flights and successful overwinter periods as a result of larger wings in better condition, reproductive diapause, and significant fat content. By contrast, Florida–Cuba migrants are more suited for shorter flights and opportunistic migratory strategies, given that their wings were in poor condition, as well as the active reproductive status of > 50% of these butterflies and their significantly low fat content. Eastern monarch migration is more complex and diverse than previously assumed. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, ?? , ??–??.  相似文献   

7.
Invasive mammals in Cuba have a negative impact on the conservation of endemic fauna. Rats, mice, mongooses, cats, dogs, among others, pose a threat to the conservation of the Cuban solenodon, the capromyid rodents, and many species of birds, reptiles, amphibians, and invertebrates. The current state of introduced and invasive mammal species in Cuba, their impact, available information about their introduction, habits, field observations, distribution, etc., is reviewed. A total of 29 species of invasive mammals in 40 islands of the Cuban Archipelago are reported; the black rat, dog, cat, mouse, mongoose, pig, goat, brown rat, and cattle are the most important. A control policy on invasive species of mammals is urgently needed for the conservation of the fauna of the Cuban Archipelago.  相似文献   

8.
The Indo-pacific panther grouper (Chromileptes altiveli) is a predatory fish species and popular imported aquarium fish in the United States which has been recently documented residing in western Atlantic waters. To date, the most successful marine invasive species in the Atlantic is the lionfish (Pterois volitans/miles), which, as for the panther grouper, is assumed to have been introduced to the wild through aquarium releases. However, unlike lionfish, the panther grouper is not yet thought to have an established breeding population in the Atlantic. Using a proven modeling technique developed to track the lionfish invasion, presented is the first known estimation of the potential spread of panther grouper in the Atlantic. The employed cellular automaton-based computer model examines the life history of the subject species including fecundity, mortality, and reproductive potential and combines this with habitat preferences and physical oceanic parameters to forecast the distribution and periodicity of spread of this potential new invasive species. Simulations were examined for origination points within one degree of capture locations of panther grouper from the United States Geological Survey Nonindigenous Aquatic Species Database to eliminate introduction location bias, and two detailed case studies were scrutinized. The model indicates three primary locations where settlement is likely given the inputs and limits of the model; Jupiter Florida/Vero Beach, the Cape Hatteras Tropical Limit/Myrtle Beach South Carolina, and Florida Keys/Ten Thousand Islands locations. Of these locations, Jupiter Florida/Vero Beach has the highest settlement rate in the model and is indicated as the area in which the panther grouper is most likely to become established. This insight is valuable if attempts are to be made to halt this potential marine invasive species.  相似文献   

9.
In 2000, a pathogenic virus was discovered in juvenile Caribbean spiny lobsters Panulirus argus from the Florida Keys, U.S.A. Panulirus argus virus 1 (PaV1) is the first naturally occurring pathogenic virus reported from lobsters, and it profoundly affects their ecology and physiology. PaV1 is widespread in the Caribbean with infections reported in Florida (U.S.A.), St. Croix, St. Kitts, Yucatan (Mexico), Belize, and Cuba. It is most prevalent and nearly always lethal in the smallest juvenile lobsters, but this declines with increasing lobster size; adults harbor the virus, but do not present the characteristic signs of the disease. No other PaV1 hosts are known. The prevalence of PaV1 in juvenile lobsters from the Florida Keys has been stable since 1999, but has risen to nearly 11% in the eastern Yucatan since 2001. Heavily infected lobsters become sedentary, cease feeding, and die of metabolic exhaustion. Experimental routes of viral transmission include ingestion, contact, and for newly settled juveniles, free virus particles in seawater. Prior to infectiousness, healthy lobsters tend to avoid diseased lobsters and so infected juvenile lobsters mostly dwell alone, which appears to reduce disease transmission. However, avoidance of diseased individuals may result in increased shelter competition between healthy and diseased lobsters, and greater predation on infected lobsters. Little is known about PaV1 outside of Mexico and the USA, but it poses a potential threat to P. argus fisheries throughout the Caribbean.  相似文献   

10.
The G protein of 23 strains of human respiratory syncytial virus isolated in Havana, Cuba, between October 1994 and January 1995 was analyzed at the antigenic and genetic level. All viruses reacted with 10 of 11 antibodies specific for the Long strain. Moreover, the G protein gene of the Cuban isolates had only five nucleotide differences from the sequence of the Long gene. The homogeneity of the Cuban isolates and their resemblance to an ancient strain, such as Long, are at odds with previous findings for viruses isolated in countries with a temperate climate and different socioeconomic status. The G proteins of three of four other viruses isolated in Havana 2 years later (1996) were also identical to those of the 1994-to-1995 isolates, and the fourth virus had a single extra nucleotide difference. This, again, is unusual, since no identical viruses had been isolated in different epidemics previously. The singular characteristics of the Cuban isolates reported here are discussed in terms of the epidemiological, climatic, and socioeconomic characteristics of Cuba.  相似文献   

11.
The possibility of cultivation of fungi on sugar cane waste (leaves and stalk tops) was tested. Having been crushed, macerated and heated, this material becomes a suitable substrate for cultivation of oyster mushrooms. Selected hybrids ofPleurotus ostreatus × P. ostreatus form Florida rapidly colonized the substrate and, in the first phase, yielded more than 10% of fresh fruiting bodies per initial mass of the wet substrate, which is considered, to be the efficiency limit of this technology. The growth cycle in Cuba is shorter than in Europe. Under the tested temperature and light conditions in Cuba, all strains formed white fruiting bodies, as compared to a multicolored variety developed in Czechoslovakia. Some of the newly obtained hybrids were found to have better properties than the original production strains. Hybrids of Cuban origin should be prepared. Besides common, well-known pests, several species of ants damage the cultures of oyster mushrooms. Translated by Č. Novotny  相似文献   

12.
Although the population of Hispaniola, Cuba's most similar neighbour in the Caribbean, continues to be threatened by parasitic diseases (including malaria), many tropical parasitic infections in Cuba have been eliminated or controlled. However, some parasitic infections remain important in the Cuban population, and the occurrence of vectors and the high possibility of introduction of parasites mean that Cuban diagnosticians must remain alert. Some key aspects of human parasitology in Cuba are reviewed here, including historical information, comparative data from Hispaniola and Jamaica, and how Cuba strives to maintain and improve its control against parasitic infections. Data from recent key novel parasitology research conducted in Cuba are also described.  相似文献   

13.
Current understanding of Cuban ichneumonids (Hymenoptera: Ichneumonoidea) is analysed. A new Subfamily (Tersilochinae) including 13 genera and two species are first reports for Cuba. In contrast with Braconidae, the sister group, the ichneumonids are poorly known because of the lack of local taxonomists and bacause nets, rather than interception, light and yellow pan traps have been used. Using Ophioninae as a reference, and comparing the percentage of ophionines in the fauna of Costa Rican ichneumonids, the ratio of species of Costa Rican to Cuban Ophioninae and the increase in the number of described Cuban ophionines, we suggest that actual Cuban biodiversity in this group may be between 400 and 600 species.  相似文献   

14.
Among crocodilians, Crocodylus rhombifer is one of the world's most endangered species with the smallest natural distribution. In Cuba, this endemic species coexists with the American crocodile (Crocodylus acutus). Hybridization between these two species is well known in captivity and might occur in the wild, but has never been demonstrated genetically. Here, we combined molecular data with environmental, geographic, and fossil data to infer the evolutionary history of Crocodylus in the Cuban Archipelago, and to evaluate genealogical support for species boundaries. We analyzed seven microsatellite loci plus DNA sequence data from nuclear (RAG-1) and mitochondrial (cytochrome b and cytochrome oxidase I) genes from 89 wild-caught individuals in Cuba, Grand Cayman Island, Jamaica, and Central America, and two samples from zoo collections. Microsatellites showed evidence of introgression, suggesting potential hybridization among Cuban groups. In Cuba, C. acutus contained one mitochondrial DNA (mtDNA) haplotype, whereas C. rhombifer contained two haplotypes. MtDNA data showed that C. acutus is paraphyletic with respect to C. rhombifer, revealing 1% sequence divergence between species within Cuba vs. 8% divergence between Cuban forms and mainland C. acutus. We suggest that hybridization has been a historical as well as a current phenomenon between C. acutus and C. rhombifer. These findings suggest that long-term conservation of crocodiles in Cuba will require identification of genetically pure and hybrid individuals, and a decrease in anthropogenic activities. We also recommend more extensive morphological and genetic analyses of Cuban population to establish clear boundaries of the hybrid zone between C. acutus and C. rhombifer.  相似文献   

15.
Ipomoea microdactyla Griseb. (Convolvulaceae) is restricted to the Bahamian archipelago, Cuba, and southeastern Florida. The species is listed as a state endangered species in Florida, where it is mostly restricted to the hyperfragmented pine rockland of Miami‐Dade County. Using seven DNA microsatellite loci, we assessed levels of genetic diversity for 12 populations of this species from Andros Island in the Bahamas (six sites), Cuba (one site), and Florida (five sites). We found significantly greater mean numbers of alleles, and higher mean values for both observed and expected heterozygosity in populations from the continuous forest on Andros than those from the habitat fragments in Florida. It is unknown if these patterns of genetic diversity in the Florida populations are the result of habitat fragmentation or founder effects. The population from Cuba exhibited relatively high levels of genetic variation, suggesting that this island is a major center of diversity and dispersal for this species. It appears that hybrid introgression for I. carolina alleles within I. microdactyla individuals occurred at a single site on Andros Island. Overall, the mean inbreeding coefficient value was 0.089, suggesting low levels of inbreeding. The highest inbreeding coefficient values were mostly recorded in Florida. Two groups were revealed, one containing the populations from Florida, and the second one encompassing those from the Bahamas and Cuba. Our results highlight the negative genetic consequences of habitat fragmentation and support initiatives recently established to establish corridors to connect the remnants of the pine forest of the Miami‐Dade County.  相似文献   

16.
Centroceras internitens n. sp. (Rhodophyceae, Ceramiaceae) was found in the Florida Keys and Bermuda only as an epiphyte on Ceramium nitens (C. Agardh) J. Agardh. It is described on the basis of many collections, including an abundance of reproductive material representing all stages of the life history. Laboratory culture has not been successful. The type locality is a well-known limestone platform on the Atlantic Ocean side of West Summerland Key, Florida Keys. In addition to living material, C. internitens was found on eight herbarium specimens of Ceramium nitens at the United States National Museum, thereby establishing records of its occurrence throughout the Caribbean Sea and dating back to 1887.  相似文献   

17.
We used ancient DNA analysis of seven museum specimens of the endangered North American ivory-billed woodpecker (Campephilus principalis) and three specimens of the species from Cuba to document their degree of differentiation and their relationships to other Campephilus woodpeckers. Analysis of these mtDNA sequences reveals that the Cuban and North American ivory bills, along with the imperial woodpecker (Campephilus imperialis) of Mexico, are a monophyletic group and are roughly equidistant genetically, suggesting each lineage may be a separate species. Application of both internal and external rate calibrations indicates that the three lineages split more than one million years ago, in the Mid-Pleistocene. We thus can exclude the hypothesis that Native Americans introduced North American ivory-billed woodpeckers to Cuba. Our sequences of all three woodpeckers also provide an important DNA barcoding resource for identification of non-invasive samples or remains of these critically endangered and charismatic woodpeckers.  相似文献   

18.
Clonal propagation is an important life history trait for many sessile organisms, and often leads to the formation of monoclonal aggregations. In the marine environment, sea anemones have been model species for testing theory regarding the evolution of sex and understanding the contribution of sexual versus asexual reproduction to the population structure in facultatively clonal animals. However, little attention has been paid to tropical actiniarians. The corkscrew anemone Bartholomea annulata is common in tropical marine habitats in the western Atlantic and Caribbean; it forms small aggregations (2–4 anemones) on coral reefs and larger aggregations (>10 anemones) in mangrove habitats. We used field surveys and molecular analyses to investigate patterns of distribution, abundance, and genetic structure of aggregations formed by B. annulata on a reef in the US Virgin Islands and in a unique mangrove habitat in the Florida Keys. Abundance was greatest at the abandoned rock quarry mangrove habitat in the Florida Keys, where anemones formed continuously distributed aggregations carpeting the exposed limestone walls. Genetic diversity assessed via intersimple sequence repeats (ISSRs) and six microsatellite loci revealed that asexual reproduction plays only a minor role in the formation of both small and large anemone aggregations. Specifically, ISSR analyses showed that only ~10% of anemone aggregations were clonal in the US Virgin Islands, while microsatellite genotyping identified clonality in only 1 of 35 aggregations. In the Florida Keys, only four clonal genotypes were recovered within aggregations, but eight clones, representing 33% of the total surveyed population, had individuals in multiple aggregations. Thus, population structure of B. annulata appears to rely primarily on sexual reproduction, although asexual reproduction may play a nontrivial role in some environments. Mechanisms that drive the formation of genotypically diverse aggregations remain unknown, but may include attraction toward conspecifics, shared use of preferred habitats, or the local retention of larvae in partially enclosed habitats.  相似文献   

19.
We used acoustic telemetry to quantify permit Trachinotus falcatus habitat use and connectivity in proximity to the Florida Keys, USA, and assessed these patterns relative to current habitat and fisheries management practices. From March 2017 to June 2018, 45 permit tagged within 16 km of the lower Florida Keys were detected at stationary acoustic receivers throughout the south Florida region, the majority of which remained within the Special Permit Zone, where more extensive fisheries harvest regulations are implemented. There was a high level of connectivity between nearshore flats (i.e., <3 m water depth) and the Florida reef tract (FRT; 15–40 m water depth), with 75% of individuals detected in both habitats. These locations probably function primarily as foraging and spawning habitats, respectively. Permit occupancy on the FRT peaked during the months of March–September, with the highest number of individuals occurring there in April and May. Specific sites on the FRT were identified as potentially important spawning locations, as they attracted a high proportion of individuals that exhibited frequent visits with high residency durations. There were also significant positive relationships between seasonal habitat-use metrics on the FRT and an empirical permit gonadosomatic index. Large aggregations of permit at spawning sites on the FRT are potentially vulnerable to the effects of fishing (including predation during catch and release) at a critical point in their life cycle. These data on permit space use and movement, coupled with knowledge of stressors on their ecology, provide insights for implementing science-based strategic management plans.  相似文献   

20.
The Paleogene tectono-sedimentary evolution of the Cuban island is dominated by block tectonics with rotations and strike-slip motion along the northern boundary of the Caribbean plate. The Capdevila Formation, which is the oldest basin fill of the Los Palacios strike-slip basin, preserves this final stage of the Cuban orogeny in western Cuba during the Early Eocene. Petrographic investigations of Capdevila Formation sedimentary records were performed at two localities near to Pinar del Rio (PR) and near to San Diégo de los Baños (SDB) close to the basin-bounding Pinar Fault zone. The studied marine hybrid arenites are interpreted as deposits of tectonically active regions causing the mixture of terrigenous and marine detritus and a differentiated development of the source areas and the basin margin. Bioclastic components (foraminifera and red algae) originate from shallow-marine carbonate platforms, being exemplarily formed at the SDB site and incompletely developed at the PR site, which is shown on the basis of foraminiferal assemblages. Among the terrigenous siliciclastic constituents, lithogenic fragments, in particular mafic to intermediate volcanic rock detritus prevail, accompanied by frequent plagioclase grains. Higher quartz portions as well as metamorphic rock clasts, which lack at the SDB site, muscovite flakes and plutonic rock fragments, characterize the lithogenic spectrum of the PR arenites. Framework composition of point-counted arenites reveal magmatic arc provenance for both successions indicating the presence of Cretaceous volcanic arc rocks on top of the northerly situated Guaniguanico Mountains, from where lithogenic detritus derived. Those findings support the idea that the North American Passive margin was overthrown by the Cretaceous volcanic arc rocks during the Cuban orogeny and affirm earlier published assumptions.  相似文献   

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