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1.
Acta amaz ; 50(1): 44-53, jan. - mar. 2020.
Artigo em Inglês | LILACS | ID: biblio-1118654

RESUMO

Diplodon granosus was one of the first freshwater mussels to be described for South America. However, the status of the species was confusing for a long time, receiving different taxonomic treatments. In this paper, we redescribe the shell, with new data on the soft parts and information on the distribution and conservation of D. granosus, a rarely recorded species. The shell is thin, not inflated; the macrosculpture is composed only by granules that cover the whole shell, not forming bars; the microsculpture comprises short spikes. In the soft parts we highlight the few, weak and irregularly distributed lamellar connections of the outer demibranch and some features of the stomach, such as the distally enlarged minor typhlosole. There are records of D. granosus over a large area of South America, from Guiana to Argentina. However, most of these records are related to other species and the distribution of D. granosus is restricted to the north of South America in the basins of the Amazonas and Orinoco rivers, and coastal rivers in between. Despite this wide distribution, the species occurs in specific habitats, mainly streams (igarapés), resulting in an extremely fragmented occurrence. Thus, any disturbance to these habitats can threat this freshwater mussel. (AU)


Assuntos
Classificação , Conservação dos Recursos Naturais , Unionidae
2.
Braz. j. biol ; 72(3): 545-552, Aug. 2012. ilus
Artigo em Inglês | LILACS | ID: lil-649343

RESUMO

The unionid Anodontites trapesilais (Lamarck, 1819) like most freshwater mussels is a parasite of fish. So it is trivial to assume that the availability of hosts is an important factor for the maintenance of unionoid populations. What seems obvious is not always so easy to demonstrate. This study proposes to investigate the effects of abiotic and biotic variables related to the incubation of larvae in A. trapesialis. For this, we estimate different biological indexes and try to capture the dimensionality of the fish, along with the temporal variation of environmental variables. From the application of a CCA, it was demonstrated that there was a synchronicity among the factors and variables proposed here, and we infer that the flood pulse acts as a synergistic factor in this process.


O bivalve Anodontites trapesilais (Lamarck, 1819), como a maioria dos mexilhões de água doce, é parasita de peixes. Então, seria trivial supor que a disponibilidade de hospedeiros é um fator importante para a manutenção das populações dos unionoideos. Porém, o que parece óbvio nem sempre é tão simples de ser demonstrado. Este estudo se propõe a investigar os efeitos de variáveis abióticas e bióticas relacionadas com a incubação de larvas de A. trapesialis. Para tanto, nós estimamos diferentes Índices Biológicos e tentamos capturar a dimensionalidade da comunidade de peixes juntamente com a variação temporal das variáveis ambientais. A partir da aplicação de uma CCA, demonstramos que há uma sincronicidade entre os fatores e as variáveis aqui propostas, e inferimos que o pulso de inundação atua como fator sinergético desse processo.


Assuntos
Animais , Peixes/parasitologia , Interações Hospedeiro-Parasita , Unionidae/fisiologia , Água Doce , Larva/fisiologia , Densidade Demográfica , Simbiose , Movimentos da Água
3.
Rev. cient. (Maracaibo) ; 18(5): 595-606, sept.-oct. 2008. tab, graf, mapas
Artigo em Espanhol | LILACS | ID: lil-548643

RESUMO

Se evaluó la calidad sanitaria de los mejillones Perna perna y P. viridis, así como de las aguas de extracción en tres zonas de producción del estado Sucre, Venezuela. Se realizaron doce muestreos entre agosto 2003 a agosto 2004. En las muestras de agua se determinó la carga (NMP/100 ml) de coliformes totales (CT) y coliformes fecales (CF), mientras que a los mejillones se les realizó recuento en placa de aerobios mesófilos (AM), carga de CF (NMP/g) y Escherichia coli, además de la detección de Salmonella spp. In situ se midió la temperatura superficial del agua, salinidad y oxígeno disuelto. El agua de las zonas de Bahía Iglesia y Punta Patilla cumplió con los criterios de CT y CF (legislación venezolana y FDA-EUA), no así la procedente de la Ensenada La Chica, en donde se obtuvo para los meses de noviembre y diciembre, valores máximos de los mismos grupos, que fueron comparativamente con los límites establecidos. Los recuentos de AM en mejillones cumplieron con los criterios microbiológicos para su comercialización establecidos por la FDA-EUA. Los mejillones procedentes de la Ensenada La Chica mostraron contaminación, ya que los CF y E. coli mostraron la cifra de los 230 NMP/g (limite permitido). Solo en una oportunidad (marzo 2004) en Bahía Iglesia, se encontraron altas cargas bacterianas en el mejillón (1,1x104 NMP/g de CF y E. coli). Se detectó Salmonella en la Ensenada La Chica solamente en octubre. No se encontró correlación entre las variables físico-químicas y las poblaciones bacterianas evaluadas. Se recomienda realizar monitoreos mensuales del agua y los mejillones para que estas zonas de producción de mejillones puedan ser clasificadas y certificadas correctamente.


The sanitary quality of the mussels, Perna perna and P. viridis, was evaluated, as well as that of the water in three zones of extraction in Sucre State, Venezuela. Twelve samplings were made between August 2003 and August 2004. In water samples, the total coliforms (TC) and fecal coliforms (FC) load were determined (MPN/100 ml), while in mussel samples a plate count of aerobial mesophils (AM), load of FC (MPN/g) and Escherichia coli were made, besides detection of Salmonella spp. In situ, the surface water temperature, salinity and dissolved oxygen were measured. Waters from Bahía Iglesia and Punta Patilla met the criteria for TC and FC (according to the Venezuelan legislation and FDA-USA), but that from Ensenada La Chica during November and December did not, since the maximum values for these two groups were comparatively higher than the allowed limits. The bacterial counts of mussels from the former two areas met the microbiological criteria for commercialization, but those from Ensenada La Chica showed an elevated contamination, since FC and E. coli surpassed the value of 230 MPN/g (allowed limit). Only in one opportunity (March, 2004) at Bahía Iglesia there was high bacterial load in mussels (1.1x104 MPN/g of FC and E. coli). Salmonella was only detected in Ensenada La Chica in October. No relationship was found between the physical and chemical variables and the evaluated bacterial loads. A periodical monitoring of water and mussels is recommended in order to have a correct classification and certification of the mussel extraction zones.


Assuntos
Bivalves/microbiologia , Coliformes/análise , Salmonella/citologia , Unionidae/microbiologia , Microbiologia da Água , Biologia Marinha
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