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1.
Folia Parasitol (Praha) ; 712024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38567406

RESUMO

Morphological data are used to describe a new nematode species, Heterocheilus floridensis sp. n. (Heterocheilidae) from the digestive tract of the Florida manatee Trichechus manatus latirostris (Harlan) (Trichechidae, Sirenia) from Florida, USA. Examination by light and scanning electron microscopy revealed that the new species differs from the related Heterocheilus tunicatus Diesing, 1839 mainly by having dentigerous ridges on the inner surface of the lips, a median unpaired papilla located anterior to the cloaca, and a considerably larger body size. Sequence data for subunits I and II of mitochondrial cytochrome oxidase gene, 18S small subunit and 28S ribosomal RNA genes were provided for molecular characterisation of the new species. However, the current unavailability of homologous sequence data for congeneric specimens precluded a molecular assessment of the morphological species hypothesis, and ascaridoid phylogenetic hypotheses could not be advanced. Specimens of Heterocheilus sp. collected from the Antillean manatee Trichechus manatus manatus Linnaeus in Puerto Rico, on loan from the US National Museum of Natural History, were morphologically consistent with the new species, so apparently all congeneric nematodes reported from both subspecies of the West Indian manatee Trichechus manatus Linnaeus and previously identified as H. tunicatus belong rather to H. floridensis sp. n. Heterocheilus hagenbecki (Khalil et Vogelsang, 1932) Sprent 1980 is here considered to be a species inquirenda. A key to valid species of Heterocheilus Diesing, 1839 is provided.


Assuntos
Nematoides , Trichechus manatus , Animais , Sirênios , Filogenia
2.
Ecology ; 102(8): e03426, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34091898

RESUMO

Estimates of age-specific survival probabilities are needed for age-structured population models and to inform conservation decisions. However, determining the age of individuals in wildlife populations is often problematic. We present a hidden Markov model for estimating age-specific survival from capture-recapture or capture-recapture-recovery data when age is unknown and indicators of age, such as size and growth layer counts, are imprecise. The model is evaluated through simulations, and its implementation is illustrated with maximum likelihood and Bayesian approaches in commonly used software. The model is then applied to genetic capture-recapture data of Florida manatees to estimate age- and time-variant survival probabilities. The approach is broadly applicable to studies aiming to quantify age-specific effects of environmental change and management actions on population dynamics, including studies that rely on minimally invasive methods such as genetic and photo identification.


Assuntos
Teorema de Bayes , Fatores Etários , Humanos , Dinâmica Populacional , Probabilidade , Incerteza
3.
Folia Parasitol (Praha) ; 682021 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-33871382

RESUMO

Two new species of philometrid nematodes (Philometridae) from needlefishes (Belonidae) in Florida are described based on morphological and genetic characteristics: Philometra aequispiculata sp. n. (males and females) collected from the ovary of Strongylura marina (Walbaum) (type host) and Strongylura notata (Poey), and Philometra notatae sp. n. (females) from the swimbladder of S. notata. Both species are described and illustrated based on light and scanning electron microscopical examinations. Morphologically, P. aequispiculata sp. n. differs from all congeners mainly in the unique structure of the distal tip of the gubernaculum, whereas P. notatae sp. n. is mainly characterised by the presence of eight markedly large cephalic papillae of the outer circle in gravid and subgravid females, the body length of the gravid female (54 mm) and by the absence of caudal projections. Molecular characterisation of the new species was assessed from phylogenetic analysis of mitochondrial cytochrome c oxidase I (COI) and SSU rRNA small-subunit ribosomal RNA (SSU) sequences among closely related philometrids by way of Bayesian inference. Phylogenetic reconstructions based on COI and SSU sequences show each of the new species comprise discrete ancestor-descendent lineages.


Assuntos
Beloniformes/parasitologia , Nematoides , Sacos Aéreos/parasitologia , Animais , Complexo IV da Cadeia de Transporte de Elétrons/genética , Estuários , Feminino , Florida , Genes de Helmintos , Masculino , Microscopia Eletrônica de Varredura , Nematoides/anatomia & histologia , Nematoides/genética , Nematoides/isolamento & purificação , Ovário/parasitologia , Filogenia , RNA Ribossômico/genética , Especificidade da Espécie
4.
Mol Ecol Resour ; 12(4): 779-81, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22642264

RESUMO

This article documents the addition of 171 microsatellite marker loci and 27 pairs of single nucleotide polymorphism (SNP) sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Bombus pauloensis, Cephalorhynchus heavisidii, Cercospora sojina, Harpyhaliaetus coronatus, Hordeum vulgare, Lachnolaimus maximus, Oceanodroma monteiroi, Puccinia striiformis f. sp. tritici, Rhea americana, Salmo salar, Salmo trutta, Schistocephalus solidus, Sousa plumbea and Tursiops aduncus. These loci were cross-tested on the following species: Aquila heliaca, Bulweria bulwerii, Buteo buteo, Buteo swainsoni, Falco rusticolus, Haliaeetus albicilla, Halobaena caerulea, Hieraaetus fasciatus, Oceanodroma castro, Puccinia graminis f. sp. Tritici, Puccinia triticina, Rhea pennata and Schistocephalus pungitii. This article also documents the addition of 27 sequencing primer pairs for Puffinus baroli and Bulweria bulwerii and cross-testing of these loci in Oceanodroma castro, Pelagodroma marina, Pelecanoides georgicus, Pelecanoides urinatrix, Thalassarche chrysostoma and Thalassarche melanophrys.


Assuntos
Bases de Dados Genéticas , Repetições de Microssatélites , Polimorfismo de Nucleotídeo Único , Ecologia , Marcadores Genéticos
5.
J Hered ; 102(4): 416-32, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21670172

RESUMO

Five diagnostic codominant nuclear DNA markers and a diagnostic mitochondrial DNA marker were used to survey weakfish (Cynoscion regalis) and sand seatrout (C. arenarius), with particular focus on heretofore uncharacterized juvenile populations along the Florida (FL) Atlantic coast. Geographic and reproductive ranges of weakfish and sand seatrout were shown to overlap on the Atlantic coast along north and central FL. An active bidirectional zone of introgressive hybridization exists between these taxa, centered in the St Johns River, FL. Strong patterns of Hardy-Weinberg, linkage, and cytonuclear disequilibrium and a bimodal hybrid index distribution were observed for juvenile cohorts in the zone center, coupled with narrow (∼240 km) concordant clines. Parental forms had disparate habitat preferences; hybrid forms occurred predominantly in intermediate habitats. All genetic data were consistent with the hypothesis that the C. arenarius-C. regalis hybrid zone is maintained by a dynamic equilibrium between continued interspecific gene flow and one or more opposing forces. Cytonuclear analyses indicated that parental forms mate assortatively in the zone but that mate recognition was imperfect. Ethological mating dynamics are likely stabilized by some form of endogenous or exogenous postfertilization selection against hybrids such that parental taxa will likely continue to evolve independently.


Assuntos
Demografia , Ecossistema , Genética Populacional , Hibridização Genética/genética , Perciformes/genética , Animais , Oceano Atlântico , DNA Mitocondrial/genética , Florida , Fluxo Gênico/genética , Marcadores Genéticos/genética , Desequilíbrio de Ligação , Comportamento Sexual Animal/fisiologia , Especificidade da Espécie
6.
Mol Ecol Resour ; 8(1): 126-8, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21585734

RESUMO

Fifteen polymorphic microsatellite DNA loci for Atlantic tarpon, Megalops atlanticus, were isolated by using PIMA, a polymerase chain reaction-based technique. The number of alleles at each locus ranged from two to 24 (mean = 7.7) in 65 specimens from Tampa Bay, Florida. Observed and expected heterozygosities ranged from 0.27 to 0.92 (mean = 0.60) and from 0.28 to 0.95 (mean = 0.62), respectively. Genotypes at one locus deviated significantly from Hardy-Weinberg equilibrium. In exact tests for genotypic disequilibrium, there was no evidence of associations between any pair of loci. Overall, loci were well resolved and highly polymorphic, confirming their suitability for DNA fingerprinting applications and other genetic studies.

7.
Mol Ecol Resour ; 8(2): 328-31, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21585782

RESUMO

Here we describe 18 polymorphic microsatellite loci for Trichechus manatus latirostris (Florida manatee), isolated using a polymerase chain reaction-based technique. The number of alleles at each locus ranged from two to four (mean = 2.5) in specimens from southwest (n = 58) and northeast (n = 58) Florida. Expected and observed heterozygosities ranged from 0.11 to 0.67 (mean = 0.35) and from 0.02 to 0.78 (mean = 0.34), respectively. Departures from Hardy-Weinberg equilibrium occurred at two loci. There was no evidence of genotypic disequilibrium for any pair of loci. For individual identification, mean random-mating and θ-corrected match probabilities were 9.36 × 10(-7) and 1.95 × 10(-6) , respectively.

8.
Mol Ecol Resour ; 8(2): 354-6, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21585790

RESUMO

Twelve polymorphic microsatellite loci were isolated for the bonefish, Albula vulpes using a polymerase chain reaction-based procedure. The number of alleles ranged from two to 23 (mean = 8.8) in 37 specimens from south Florida. Observed and expected heterozygosities ranged from 0.07 to 0.77 (mean = 0.42) and from 0.07 to 0.84 (mean = 0.48), respectively. There were no significant departures from Hardy-Weinberg equilibrium and no evidence of genotypic disequilibrium between any pair of loci. In a cross-amplification test, all markers yielded appropriately sized alleles for specimens of the provisional Albula sp. B and 11 of the 12 loci amplified for those of Albula glossodonta.

9.
Mol Ecol Resour ; 8(3): 650-2, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-21585860

RESUMO

We describe 10 microsatellite loci for Panulirus argus (Caribbean spiny lobster). The number of alleles at each locus ranged from four to 39 (mean = 21.8) in 89 juvenile specimens collected at two different times at a recruitment site in south Florida. Levels of expected and observed heterozygosities ranged from 0.48 to 0.96 (mean = 0.83) and from 0.32 to 0.98 (mean = 0.71), respectively. Significant departures from Hardy-Weinberg equilibrium were observed at two loci. There was no evidence of genotypic disequilibrium for any pair of loci. Overall, the loci were well resolved, highly polymorphic and independently segregating, confirming their utility for population genetic studies.

10.
Mar Biotechnol (NY) ; 6(2): 175-85, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14586768

RESUMO

The mitochondrial DNA control regions of red snapper (Lutjanus campechanus) from the Gulf of Mexico (n = 140) and Atlantic coast of Florida (n = 35) were sequenced to generate a prestocking genetic baseline for planned stock enhancement. Intrasample haplotype and nucleotide diversities ranged from 0.94 to 1.00 and 1.8% to 2.5%, respectively. All population analyses were consistent with the hypothesis that red snapper constitute a single, panmictic population over the sampled range. A ubiquitous, predominant haplotype, shared by 23% of the specimens, appeared to be evolutionarily recent, in contrast to previous findings based on restriction fragment length polymorphism data. Tajima's D values were suggestive of a recent bottleneck. Mismatch distributions from Gulf samples were smooth and unimodal, characteristic of recent population expansion. However, the Atlantic sample exhibited a comparatively broader, possibly multimodal distribution, suggestive of a more stable population history. Additional control-region data may clarify potentially disparate demographic histories of Gulf and Atlantic snapper.


Assuntos
DNA Mitocondrial/genética , Evolução Molecular , Variação Genética , Genética Populacional , Perciformes/genética , Animais , Oceano Atlântico , Sequência de Bases , Análise por Conglomerados , Geografia , Haplótipos/genética , Região de Controle de Locus Gênico/genética , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA
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