Results 211 to 220 of about 1,823 (231)

Phylogeography, genetic diversity and population structure of the freshwater stingray, Paratrygon aiereba (Müller & Henle, 1841) (Myliobatiformes: Potamotrygonidae) in the Colombian Amazon and Orinoco basins

Mitochondrial DNA. Part A, DNA mapping, sequencing, and analysis, 2020
The freshwater stingray Paratrygon aiereba have coloration, osteological and morphometric variations that could suggest the existence of more than one species in Colombia.
Maira A. Rizo-Fuentes, Camilo A. Correa-Cárdenas, C. Lasso, Mónica A Morales-Betancourt, Dalia C. Barragán-Barrera, S. Caballero   +5 more
semanticscholar   +1 more source

Stingers in a strange land: South American freshwater stingrays (Potamotrygonidae) in Singapore

Biological Invasions, 2009
South American freshwater stingrays of the family Potamotrygonidae have long been popular worldwide as ornamentals in the aquarium trade. Despite this, there have so far not been any reported cases of their establishment elsewhere in the world. Here, we document the ocellate river stingray, Potamotrygon motoro, as having established itself in Singapore.
Ng, H.H., Tan, H.H., Yeo, D.C.J., Ng, P.K.L.   +3 more
openaire   +1 more source

Morphology of the Digestive Tube of the Amazonian Freshwater Stingray Potamotrygon wallacei (Elasmobranchii: Potamotrygonidae): A Stereological Approach

Journal of morphology
This work aimed to describe and quantify the tissue components of the digestive tube of the neotropical freshwater stingray, Potamotrygon wallacei. For this, conventional histology and stereological methods were used to estimate tissue volume.
R. Machado, W. Duncan
semanticscholar   +1 more source

Potamotrygon marquesi, a new species of neotropical freshwater stingray (Potamotrygonidae) from the Brazilian Amazon Basin.

Journal of Fish Biology, 2019
Potamotrygon marquesi, sp. nov., is described and compared with other species of Potamotrygon occurring in the Amazon Basin. The identity of this new species is supported by an extensive external and internal morphological study including coloration ...
João Paulo Capretz Batista da Silva, Thiago Silva Loboda   +1 more
semanticscholar   +1 more source

Systematics and morphology of Potamotrygon orbignyi (Castelnau, 1855) and allied forms (Chondrichthyes: Myliobatiformes: Potamotrygonidae)

Zootaxa, 2015
The Neotropical freshwater stingray Potamotrygom orbignyi (Castelnau, 1855), and other similar "reticulated" species occurring in northern South American basins, were submitted to a thorough taxonomic analysis based on an extensive external and internal morphological study. The identity of P.
João Paulo C B Da, Silva, Marcelo R De, Carvalho   +1 more
openaire   +2 more sources

The neurocranium of Potamotrygonidae: morphology and phylogenetic significance

Zoological Journal of the Linnean Society
Abstract The family Potamotrygonidae is part of the Neotropical ichthyofauna and has the largest diversity of freshwater elasmobranchs in the world. The neurocranium in Potamotrygonidae is an elongated and dorsoventrally flattened structure that articulates anterolaterally with the anterior portion of the propterygium, posteriorly with ...
Marcus V G Araújo, Diego F B Vaz, Jade Medeiros, Arthur de Lima, Ricardo S Rosa, Thiago S Loboda, João Paulo C B da Silva   +6 more
openaire   +1 more source

Chromosomes of three freshwater stingrays (Rajiformes Potamotrygonidae) from the Rio Negro basin, Amazon, Brazil

Genetica, 2006
Potamotrygonidae is the representative family of South American freshwater elasmobranchs. It is a monophyletic group containing 20 species grouped into three genera. Three species belonging to two genera of this family were collected from the middle Negro River, Amazonas, Brazil, and studied cytogenetically: Paratrygon aiereba, Potamotrygon motoro and ...
Valentim, Francisco Carlos Souza de, Falcão, José das Neves, Porto, Jorge Ivan Rebelo, Feldberg, Eliana   +3 more
openaire   +3 more sources

Mitochondrial DNA diversity and population structure of the ocellate freshwater stingray Potamotrygon motoro (Müller & Henle, 1841) (Myliobatiformes: Potamotrygonidae) in the Colombian Amazon and Orinoco Basins

Mitochondrial DNA. Part A, DNA mapping, sequencing, and analysis, 2019
The lack of clarity regarding the taxonomy of the ocellate river stingray (Potamotrygon motoro) and the absence of previous studies regarding its genetic diversity and population structure makes this species vulnerable to overexploitation, being now the ...
Mariana Renza-Millán, C. Lasso, Mónica A Morales-Betancourt, F. Villa, S. Caballero   +4 more
semanticscholar   +1 more source

Plesiotrygon iwamae, a New Genus and Species of Neotropical Freshwater Stingray (Chondrichthyes: Potamotrygonidae)

Copeia, 1987
A new genus and species of neotropical freshwater stingray are described from the upper and mid-Amazon drainage, in Ecuador and Brazil (Rio Napo and Rio Solimbes). The new taxa are characterized by a long filiform tail, reduced eyes, and low number of pectoral-fin radials.
Ricardo S. Rosa, Hugo P. Castello, Thomas B. Thorson   +2 more
openaire   +1 more source

Clasper gland morphology and development in Potamotrygon magdalenae (Elasmobranchii: Potamotrygonidae).

Journal of morphology, 2017
Clasper gland morphology and development in Potamotrygon magdalenae and its relation with the acquisition of reproductive maturity is described in males of different developmental stages (embryos, neonates, juveniles, and reproductively active and resting adults). The glands are subcutaneous masses in the proximal base of each clasper.
Paola, Anaya-López, Martha Patricia, Ramírez-Pinilla   +1 more
openaire   +1 more source