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1.
Invertebr Syst ; 382024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38744497

RESUMEN

Despite the widespread use of integrative taxonomic approaches, many scleractinian coral genera and species remain grouped in polyphyletic families, classified as incertae sedis or simply understudied. Oculinidae Gray, 1847 represents a family for which many taxonomic questions remain unresolved, particularly those related to some of the current genera, such as Oculina Lamark, 1816 or recently removed genera, including Cladocora Ehrenberg, 1834 and Madrepora Linnaeus, 1758. Cladocora is currently assigned to the family Cladocoridae Milne Edwards & Haime, 1857 and a new family, Bathyporidae Kitahara, Capel, Zilberberg & Cairns, 2024, was recently raised to accommodate Madrepora . However, the name Bathyporidae is not valid because this was not formed on the basis of a type genus name. To resolve taxonomic questions related to these three genera, the evolutionary relationships are explored through phylogenetic analyses of 18 molecular markers. The results of these analyses support a close relationship between the species Oculina patagonica and Cladocora caespitosa , indicating that these may belong to the same family (and possibly genus), and highlighting the need for detailed revisions of Oculina and Cladocora . By contrast, a distant relationship is found between these two species and Madrepora oculata , with the overall evidence supporting the placement of Madrepora in the resurrected family Madreporidae Ehrenberg, 1834. This study advances our knowledge of coral systematics and highlights the need for a comprehensive review of the genera Oculina , Cladocora and Madrepora .


Asunto(s)
Antozoos , Filogenia , Animales , Antozoos/clasificación , Especificidad de la Especie
2.
Rev. biol. trop ; 68(3)sept. 2020.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1507696

RESUMEN

Introducción: El conocimiento de la Clase Ophiuroidea es muy escaso y deficiente, a pesar de ser la que presenta el mayor número de especies del Filo Echinodermata con hasta 2 100. Además, apenas existen publicaciones dedicadas específicamente al grupo de las ofiuras en la vertiente pacífica de Costa Rica. Objetivo: La caracterización morfológica y genética de las ofiuras de la franja intermareal y sublitoral somero del Parque Nacional Marino Las Baulas (Pacífico de Costa Rica). Métodos: El periodo de recolecta se extendió entre enero y abril de 2018 y tuvo lugar a lo largo de siete localidades: Punta del Morro, Playa Carbón, Playa Ventanas, Playa Grande, Playa Tamarindo Ciudad, Playa Tamarindo y Playa Langosta. Se ha realizado la caracterización de 214 ofiuras mediante claves taxonómicas, descripciones originales y el marcador mitocondrial citocromo c oxidasa subunidad I (COI). Resultados: En total, combinando los caracteres morfológicos y genéticos, se han identificado 11 especies, cuatro de las cuales podrían ser nuevas, nueve constituyen nuevos registros en el parque y una de las especies se ha encontrado por primera vez en Costa Rica (Ophiophragmus aff. stellatus). Además, se han identificado individuos juveniles y se han encontrado dos especies crípticas. Conclusión: Del estudio molecular se concluye que el marcador COI es útil para delimitar molecularmente las especies y establecer relaciones filogenéticas para los niveles taxonómicos de género y especie, pero no para los superiores. Se aportan observaciones morfológicas e imágenes como contribución a la taxonomía del grupo.


Introduction: Information on the class Ophiuroidea is very scarce, despite it consisting of the highest number of species within the phylum Echinodermata, with up to 2 100 species. In particular, there are hardly any study focused specifically to ophiuroids found along the Pacific coast of Costa Rica. Objective: Morphological and genetic characterization of ophiuroids of the shallow intertidal and sublittoral areas of Las Baulas Marine National Park (Pacific coast of Costa Rica). Methods: Sampling was conducted between January and April of 2018 at seven locations: Punta del Morro, Playa Carbón, Playa Ventanas, Playa Grande, Playa Tamarindo Ciudad, Playa Tamarindo and Playa Langosta. A total of 214 ophiuroids were characterized using taxonomic keys and original descriptions and a molecular analysis of the mitochondrial Cytochrome oxidase I (COI) gene. Results: An analysis of morphological and genetic characters indicates that 11 species are present in the study site. Four may represent new species, nine constitute new records for the area and one (Ophiophragmus aff. stellatus) is recorded in Costa Rica for the first time. Additionally, juvenile individuals of different species were identified, and two cryptic species were detected. Conclusions: According to the molecular analysis, COI is useful to delimit ophiuroid species and to establish phylogenetic relationships at lower (genera and species) but not higher taxonomic levels. This study also provides images and morphological remarks for future comparative studies.

3.
PLoS One ; 7(11): e50215, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23209679

RESUMEN

The cosmopolitan solitary deep-water scleractinian coral Desmophyllum dianthus (Esper, 1794) was selected as a representative model species of the polyphyletic Caryophylliidae family to (1) examine phylogenetic relationships with respect to the principal Scleractinia taxa, (2) check population structure, (3) test the widespread connectivity hypothesis and (4) assess the utility of different nuclear and mitochondrial markers currently in use. To carry out these goals, DNA sequence data from nuclear (ITS and 28S) and mitochondrial (16S and COI) markers were analyzed for several coral species and for Mediterranean populations of D. dianthus. Three phylogenetic methodologies (ML, MP and BI), based on data from the four molecular markers, all supported D. dianthus as clearly belonging to the "robust" clade, in which the species Lophelia pertusa and D. dianthus not only grouped together, but also shared haplotypes for some DNA markers. Molecular results also showed shared haplotypes among D. dianthus populations distributed in regions separated by several thousands of kilometers and by clear geographic barriers. These results could reflect limited molecular and morphological taxonomic resolution rather than real widespread connectivity. Additional studies are needed in order to find molecular markers and morphological features able to disentangle the complex phylogenetic relationship in the Order Scleractinia and to differentiate isolated populations, thus avoiding the homoplasy found in some morphological characters that are still considered in the literature.


Asunto(s)
Dianthus/fisiología , Animales , Antozoos , Secuencia de Bases , Núcleo Celular/metabolismo , ADN/genética , ADN Intergénico/metabolismo , ADN Mitocondrial/genética , Ecosistema , Evolución Molecular , Variación Genética , Genética de Población , Haplotipos , Región Mediterránea , Mitocondrias/metabolismo , Filogenia , Reacción en Cadena de la Polimerasa/métodos , Polimorfismo Genético , Análisis de Secuencia de ADN
4.
Mol Phylogenet Evol ; 54(1): 179-86, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19706330

RESUMEN

We studied phylogenetic relationships of the Eleutherodactylus auriculatus species group to infer colonization and diversification patterns in this endemic radiation of terrestrial frogs of the genus Eleutherodactylus in the largest of the Greater Antilles, Cuba. An initial screening of genetic diversity based on partial sequences of the 16S rRNA gene in almost 100 individuals of all species of the group and covering the complete known geographic range of their occurrence found most species endemic to small ranges in the eastern Cuban mountains while a single species was widespread over most of Cuba. Our molecular phylogeny, based on 3731 bp of four mitochondrial and one nuclear gene, suggests that most cladogenetic events within the group occurred among clades restricted to the eastern mountains, which acted as refugia and facilitated the diversification in this group. Our results reveal two separate colonization events of Central and Western Cuba and allow inferring the timing of the subsequent diversification events that occurred between 11 and 2 Mya. Because populations previously assigned to E. auriculatus represent four genetically strongly divergent lineages that also differ in their advertisement calls, we propose that E. auriculatus as currently recognized comprises four species. The difficulties in assigning the name auriculatus to any of these four species, and the fact that E. principalis is nested within one of them, stress the need for a thorough taxonomic revision of this group.


Asunto(s)
Anuros/genética , Núcleo Celular/genética , ADN Mitocondrial/genética , Evolución Molecular , Filogenia , Animales , Anuros/clasificación , Cuba , Especiación Genética , Geografía , Alineación de Secuencia , Análisis de Secuencia de ADN
5.
Mol Phylogenet Evol ; 33(2): 259-79, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15336662

RESUMEN

Squat lobsters (genus Munida and related genera) are among the most diverse taxa of western Pacific crustaceans, though several features of their biology and phylogenetic relationships are unknown. This paper reports an extensive phylogenetic analysis based on mitochondrial DNA sequences (cytochrome c oxidase subunit I and 16S rRNA) and the morphology of 72 species of 12 genera of western Pacific squat lobsters. Our phylogenetic reconstruction using molecular data supports the recent taxonomic splitting of the genus Munida into several genera. Excluding one species (M. callista), the monophyly of the genus Munida was supported by Bayesian analysis of the molecular data. Three moderately diverse genera (Onconida, Paramunida, and Raymunida) also appeared monophyletic, both according to morphological and molecular data, always with high support. However, other genera (Crosnierita and Agononida) seem to be para- or polyphyletic. Three new cryptic species were identified in the course of this study. It would appear that the evolution of this group was marked by rapid speciation and stasis, or certain constraints, in its morphological evolution.


Asunto(s)
Anomuros/clasificación , Anomuros/genética , ADN Mitocondrial/genética , Evolución Molecular , Filogenia , Animales , Anomuros/anatomía & histología , Complejo IV de Transporte de Electrones/genética , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
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