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1.
Zebrafish ; 17(1): 38-47, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31994993

RESUMO

Neotropical cichlids include hundreds of species whose taxonomy has benefited of molecular phylogeny and whose karyotype evolution has been related to the amount and distribution of different classes of repetitive sequences. This study provides the first integrative molecular (cytochrome c oxidase subunit 1 and 16S sequences) and cytogenetic analyses of wild samples of the green terror Andinoacara rivulatus, a cichlid naturally distributed in Ecuador and spread throughout the world as an aquarium pet. Molecular data revealed that sequences of green terror constitute a single monophyletic clade within the genus and allowed species attribution of uncertain samples previously cytogenetically analyzed. Chromosome number (2n = 48) conforms to the general trend observed within neotropical cichlids. However, mapping of different classes of repeated sequences (18S rDNA, 5S rDNA, U1 snDNA and telomeric) revealed the presence of features uncommon among representatives of these fishes, like multiple major rDNA sites, and suggested a recent occurrence of rearrangements (fusion/inversion) in two chromosome pairs.

2.
Zootaxa ; 4671(3): zootaxa.4671.3.5, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31716044

RESUMO

Mugil setosus Gilbert 1892 was originally described by Gilbert based on specimens from Clarion Island, in the western and most remote of the Revillagigedo Islands, about 1,000 km off the western Pacific coast of Mexico. Examination of the type of material and recently collected specimens from Ecuador and Peru, resulted in the redescription provided herein. Diagnostic characters of the species were mainly: tip of the pelvic fin reaching beyond the vertical through the base of the third dorsal-fin spine, the pectoral-fin rays with ii+13-14 rays, the anterodorsal tip of second (soft) dorsal fin uniformly dark, and an external row of larger teeth, and more internally a patch of scattered smaller teeth, visible mainly in adults 150 mm SL. The expansion of geographic distribution of Mugil setosus and occurrence of Mugil curema Valenciennes 1836 in the Pacific Ocean are discussed.


Assuntos
Perciformes , Animais , Equador , Ilhas , México , Oceano Pacífico , Peru
3.
Neotrop. ichthyol ; 17(1): e170123, 2019. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-990196

RESUMO

Moenkhausia bonita occurs in numerous additional localities from the Bermejo, Paraná, Paraguay, and Uruguay river basins. Given that this finding greatly expands the distributional range of M. bonita, we carried out an intraspecific comparison, using multivariate methods for 18 morphometric and eight meristic characters taken from a comprehensive sample of 536 specimens. All localities were distributed in four major geographic groups as follows: Bermejo, Paraná, Paraguay, and Uruguay. Results of the morphometric comparisons showed significant differences among the studied groups except between the Paraguay and Uruguay groups. Statistical differences in meristic values were found for most between-group comparisons, especially in those resulting from discriminant canonical analyses (DCA). Specimens from the Bermejo basin were the most distinct group in most morphological comparisons. However, the overall subtle differences found in body morphology likely reflect intraspecific variation within M. bonita and seem to be mainly influenced by spatial and environmental features of drainages. As M. bonita was previously identified as M. intermedia in the río de La Plata basin, distributional comments on the latter species in that basin are provided.(AU)


Moenkhausia bonita es registrada en numerosas localidades adicionales de las cuencas de los ríos Bermejo, Paraná, Paraguay, y Uruguay. Dado que estos hallazgos expanden ampliamente el rango distribucional de M. bonita, nosotros llevamos a cabo una comparación intraespecífica, usando métodos multivariados para 18 características morfométricas y 8 merísticas que fueron tomados en una muestra exhaustiva de 536 especímenes. Todas las localidades fueron repartidas en cuatro grupos principales como sigue: Bermejo, Paraná, Paraguay y Uruguay. Los resultados de las comparaciones morfométricas mostraron diferencias significativas a través de los grupos bajo estudio, excepto entre los grupos Paraguay y Uruguay. Diferencias estadísticas fueron encontrados en la mayoría de las comparaciones entre los grupos, especialmente en aquellas obtenidas de los análisis discriminantes canónicos (ADC). Los especímenes de la cuenca del Bermejo fueron encontrados como el grupo más divergente en la mayoría de las comparaciones morfológicas. No obstante, estas leves diferencias encontradas en la morfología del cuerpo son consideradas dentro de la variación intraespecífica de M. bonita y parecen estar influidas por características ambientales y espaciales de los drenajes. Dado que M. bonita fue previamente identificada como M. intermedia en la cuenca del río de La Plata, comentarios distribucionales sobre esta última especie en esta cuenca son presentados.(AU)


Assuntos
Animais , Characidae/crescimento & desenvolvimento , Geomorfologia
4.
Neotrop. ichthyol ; 16(2): [e170086], jun. 2018. ilus, graf, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-948562

RESUMO

A new species of Moenkhausia is described from tributaries of the upper rio Sepotuba, Paraguay basin, Brazil. The new species is distinguished from its congeners by a combination of characters, including an inconspicuous oval-shaped vertically elongated humeral blotch, extending horizontally from third through five lateral-line scales, and vertically from third row above lateral line to first row below it, followed by a diffuse field of dark chromatophores in the flank, combined with a well-defined dark line at the base of the anal fin. Furthermore, the phylogenetic position of the new species is presented based on molecular data, showing a close relationship among species of Moenkhausia and Hemigrammus that have a well-defined dark line at the base of the anal fin. Until this moment, this species is only known from in the upper rio Sepotuba basin.(AU)


Uma nova espécie de Moenkhausia é descrita nos afluentes do rio Sepotuba, bacia do Paraguai, no Brasil. A nova espécie se distingue dos seus congêneres por uma combinação de caracteres, incluindo uma mancha umeral discreta de forma oval, alongada verticalmente, que se estende horizontalmente da terceira a quinta escamas da linha lateral e, verticalmente, da terceira fila de escamas acima da linha lateral até a primeira fila abaixo da linha lateral; seguida por escassos cromatóforos no flanco, combinado com uma linha escura bem definida na base da nadadeira anal. Além disso, a posição filogenética da nova espécie é apresentada com base em dados moleculares, mostrando um relacionamento próximo entre as espécies de Moenkhausia e Hemigrammus que possuem uma linha escura bem definida na base da nadadeira anal. Até o momento, essa espécie é conhecida apenas da bacia do Alto Sepotuba.(AU)


Assuntos
Animais , Filogenia , Characidae/classificação , Characidae/genética
5.
Zookeys ; (606): 127-40, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27551225

RESUMO

The Amazon Basin occupies a vast portion of northern South America and contains some of the highest species richness in the world. The northern Brazilian state of Amapá is delimited by the Amazonas River to the south, the Oyapock River to the northern boundary with French Guyana, and the Atlantic northeastern coast to Amazon estuary. Despite several expeditions to the Amazon in recent decades, little is known about the freshwater ichthyofauna from Amapá, with records limited to local inventories and species descriptions. This paper presents a compilation of the freshwater fish diversity sampled in fifteen sites covering two major Amapá ecoregions during the dry season of 2015. 120 species representing eight orders and 40 families are reported upon in this work. Eight species appear for the first time in the Brazilian territory providing new information for future conservation status evaluations.

6.
Zootaxa ; 4114(2): 123-38, 2016 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-27395119

RESUMO

The Hypsolebias antenori species group comprises a monophyletic clade of annual fishes occurring in the semi-arid region of Northeastern Brazil. Most species of this group are found in the Rio São Francisco basin, but there are three species that inhabit small coastal basins. Hypsolebias faouri new species, is described from a temporary pool located near Rio Preto, a tributary of the Rio São Francisco, and Hypsolebias martinsi new species, is described from an annual pool near Rio Icaraizinho, a coastal drainage. Molecular data corroborates the monophyly of Hypsolebias and both new species.


Assuntos
Ciprinodontiformes/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Brasil , Ciprinodontiformes/anatomia & histologia , Ciprinodontiformes/crescimento & desenvolvimento , Ecossistema , Feminino , Masculino , Tamanho do Órgão
7.
Zootaxa ; 3869(4): 409-19, 2014 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-25283927

RESUMO

Apistogramma ortegai, new species, is described from small streams tributaries of the Ampiyacu River near Pebas, in eastern Peru. It belongs to the Apistogramma regani species group and is distinguished from all other species of Apistogramma by the combination of contiguous caudal spot to bar 7, presence of abdominal stripes, short dorsal-fin lappets in both sexes, absence of vertical stripes on the caudal fin, and reduced number of predorsal and prepelvic scales.


Assuntos
Ciclídeos/anatomia & histologia , Ciclídeos/classificação , Animais , Feminino , Masculino , Peru , Rios
8.
Zookeys ; (406): 1-23, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24843279

RESUMO

A new species of Pseudancistrus is described from the Tapajós Basin, and assigned to the P. barbatus group by having hypertrophied odontodes along the snout and lacking evertible cheek plates. The new species is distinguished from other species in that group (P. barbatus, P. corantijniensis, P. depressus and P. nigrescens) by its pattern of spots, length and color of snout odontodes, greater head depth, cleithral width, anal-fin spine length, peduncle depth and internares width. Molecular phylogenetic results corroborate placement of the new species in the Pseudancistrus barbatus group which is otherwise distributed in the Xingu Basin and rivers draining the Guyana Shield into the Atlantic Ocean. Topology tests strongly reject alternative hypotheses supporting close relationships with Guyanancistrus, Lithoxancistrus or the species Pseudancistrus pectegenitor, P. sidereus and P. genisetiger. Additionally, we propose two hypotheses on the distribution of the new species in the rio Tapajós, a Brazilian Shield drainage. The first one proposes that ancestral stock of the P. barbatus group was widely distributed throughout rivers draining the Guyana and Brazilian shields, and the species P. zawadzkii and Pseudancistrus sp. L17 are in the limit of the distribution for the group in Tapajós and Xingu rivers. The second hypothesis proposes that ancestral stock of the P. barbatus group was restricted to Guyana Shield rivers, and that headwater capture events permitted several dispersal routs through Guyana and Amazon rivers, permitted that the ancestral lineages of Pseudancistrus sp. L17 and P. zawadzkii reached the rivers of Amazon basin.

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