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The effect of abiotic factors on the hatching of Moina micrura Kurz, 1874 (Crustacea: Cladocera) ephippial eggs
ROJAS, N. E. T.;MARINS, M. A.;ROCHA, O.;
Brazilian Journal of Biology , 2001, DOI: 10.1590/S1519-69842001000300005
Abstract: the roles of some abiotic factors in controlling the hatching rates of moina micrura ephippial eggs were investigated. determination of optimum hatching conditions would be important in developing the use of this species as a food for fish larvae in aquaculture. ephippia were exposed to different treatments in the laboratory, and monitored for hatching over a period of seven days. optimum hatching conditions were: ph 5-9, temperature 25oc, photoperiod eight or more hours light per day and light intensity equal to or greater than 850 lux. differences in water ionic concentrations (from deionized water to 880 mg.l-1 of selected salts) had no effect.
The effect of abiotic factors on the hatching of Moina micrura Kurz, 1874 (Crustacea: Cladocera) ephippial eggs  [cached]
ROJAS N. E. T.,MARINS M. A.,ROCHA O.
Brazilian Journal of Biology , 2001,
Abstract: The roles of some abiotic factors in controlling the hatching rates of Moina micrura ephippial eggs were investigated. Determination of optimum hatching conditions would be important in developing the use of this species as a food for fish larvae in aquaculture. Ephippia were exposed to different treatments in the laboratory, and monitored for hatching over a period of seven days. Optimum hatching conditions were: pH 5-9, temperature 25oC, photoperiod eight or more hours light per day and light intensity equal to or greater than 850 lux. Differences in water ionic concentrations (from deionized water to 880 mg.L-1 of selected salts) had no effect.
Conducta alimentaria de Daphnia ambigua Scourfield 1947, Moina micrura Kurz 1874 y Ceriodaphnia dubia Richard 1895 (Cladocera) frente a un gradiente de concentración de alimento
MARTINEZ,GINGER;
Revista chilena de historia natural , 2000, DOI: 10.4067/S0716-078X2000000100006
Abstract: because cladocera is the most abundant group of filter-feeders in the freshwater zooplankton and their populations are usually found under limited resources conditions, the individual response under a resources concentration gradient has important consequences on the population and community patterns. feeding behavior of moina micrura, ceriodaphnia dubia and daphnia ambigua (cladocera) on the microalgae chlorella sp. and oocystis sp. (chlorophyceae) was compared by using the following parameters: maximum ingestion rate (imax), incipient limiting concentration (ilc) and consumption efficiency (b), which were obtained through a model of functional response. results indicated that d. ambigua showed the highest imax and ilc on both resources, however, this specie presented the lowest b. whereas, d. ambigua did not show differences in b on chlorella sp. or oocystis sp., m. micrura showed a higher b on chlorella sp. and c. dubia on oocystis sp. these results reveal significant interspecific differences in the feeding response of cladocera, which showed a complex behavior exposed to variations in the availability of food resources
Conducta alimentaria de Daphnia ambigua Scourfield 1947, Moina micrura Kurz 1874 y Ceriodaphnia dubia Richard 1895 (Cladocera) frente a un gradiente de concentración de alimento Feeding behaviour of Daphnia ambigua Scourfield 1947, Moina micrura Kurz 1874 and Ceriodaphnia dubia Richard 1895 (Cladocera) under a food concentration gradient  [cached]
GINGER MARTINEZ
Revista chilena de historia natural , 2000,
Abstract: Debido a que Cladocera es el grupo de microfiltradores más abundante del zooplancton límnico y cuyas poblaciones se encuentran usualmente limitadas por alimento, la respuesta de los individuos frente a un gradiente de concentración de recursos tendría significativas implicancias sobre los patrones poblacionales y comunitarios. Se comparó la conducta alimentaria de Moina micrura, Ceriodaphnia dubia y Daphnia ambigua (Cladocera) frente a las microalgas Chlorella sp. y Oocystis sp. (Chlorophyceae) mediante los siguientes parámetros: Tasa de Ingesta Máxima (Imax), Concentración Limitante Incipiente (CLI) y Eficiencia de Consumo (b), los cuales fueron obtenidos a través de un modelo de respuesta funcional. Los resultados mostraron que D. ambigua presentó las mayores Imax y CLI sobre ambos recursos, sin embargo, esta especie presentó la menor b. Mientras que D. ambigua no presentó diferencias en b sobre Chlorella sp. y Oocystis sp., M. micrura presentó una mayor b sobre Chlorella sp. y C. dubia sobre Oocystis sp. Estos resultados revelan significativas diferencias interespecíficas en la respuesta alimentaria de Cladocera, grupo que presentó un complejo comportamiento frente a variaciones en la disponibilidad de recursos alimentarios Because Cladocera is the most abundant group of filter-feeders in the freshwater zooplankton and their populations are usually found under limited resources conditions, the individual response under a resources concentration gradient has important consequences on the population and community patterns. Feeding behavior of Moina micrura, Ceriodaphnia dubia and Daphnia ambigua (Cladocera) on the microalgae Chlorella sp. and Oocystis sp. (Chlorophyceae) was compared by using the following parameters: Maximum Ingestion Rate (Imax), Incipient Limiting Concentration (ILC) and Consumption Efficiency (b), which were obtained through a model of functional response. Results indicated that D. ambigua showed the highest Imax and ILC on both resources, however, this specie presented the lowest b. Whereas, D. ambigua did not show differences in b on Chlorella sp. or Oocystis sp., M. micrura showed a higher b on Chlorella sp. and C. dubia on Oocystis sp. These results reveal significant interspecific differences in the feeding response of Cladocera, which showed a complex behavior exposed to variations in the availability of food resources
Distribution and abundance of Cladocera (Branchiopoda) in the Paraíba do Sul River estuary, Rio de Janeiro, Brazil
Sterza, José Mauro;Fernandes, Luiz Loureiro;
Brazilian Journal of Oceanography , 2006, DOI: 10.1590/S1679-87592006000300003
Abstract: to characterize the cladoceran community of the paraíba do sul river estuary, located in the district of s？o jo？o da barra, rio de janeiro, brazil, cladocerans were collected monthly in nine sampling stations from september 2002 until august 2003. samples were obtained by subsurface tows using a plankton net with a 30 cm opening mouth and 70 micron mesh size, fitted with a mechanical flowmeter. environmental parameters such as salinity and temperature were also obtained. seventeen species of cladocera were identified: pseudoevadne tergestina, penilia avirostris, macrothrix triserialis, moina micrura, simocephalus kerhervei, simocephalus vetalus, simocephalus latirostris, simocephalus serrulatus, alona rectangula, alona quadrangularis, bosmina longirostris, bosminopsis deitersi, camptocercus dadayi, ceriodaphnia richardi, diaphanosoma fluviatile, kurzia latissima and pleuroxus similis. the highest total abundance of cladocera occurred in april in the marine zone of the estuary. the most abundant species during this period was penilia avirostris. at the mixing and freshwater zones of the estuary, the most abundant species were moina micrura, mainly in january; and simocephalus vetalus and bosmina longirostris during spring. from this scenario, it can be inferred that the cladoceran community of the paraíba do sul river estuary presents characteristics of marine, brackish and freshwater environments. temperature and salinity seem to limit the occurrence and distribution of cladocerans in the estuary.
Population dynamics of Moina minuta Hansen (1899), Ceriodaphnia cornuta Sars (1886), and Diaphanosoma spinulosum Herbst (1967) (Crustacea: Branchiopoda) in different nutrients (N and P) concentration ranges
Vieira, Ana Carolina Brito;Medeiros, Ana Maria Alves;Ribeiro, Leonardo Le？ncio;Crispim, Maria Cristina;
Acta Limnologica Brasiliensia , 2011, DOI: 10.4322/actalb.2011.018
Abstract: aim: aquatic environments of semi-arid regions are subject to changes in water quality and volume due to short and irregular rain seasons. consequently, zooplankton composition changes in association to fluctuations in the trophic degree. to comprehend these processes, this study analyzed the influence of nutrient concentrations (n and p) on the population dynamics of three species of cladocera - moina minuta, ceriodaphnia cornuta, and diapahnosoma spinulosum - from the taperoá ii dam, paraíba, brazil; methods: animals were experimentally submitted to different nutrient concentrations as a means to reproduce specific trophic conditions from natural environments. zooplankton densities were evaluated once every three days, with food (i.e. algal cultures) being supplied in alternate days. to compare population growth, an anova was performed, followed by tukey's hsd post-hoc test; results: the population growth of the three species differed significantly both among species and among treatments. moina minuta populations showed higher growth rates under higher nutrient concentrations, whereas ceriodaphnia cornuta growed more efficiently in intermediate concentrations, and diaphanosoma spinulosum showed a better development in low nutrient concentrations; conclusions: the results from the experimental approach, presented here, are similar to what is observed in the field, based on previous studies carried out in the taperoá ii dam. therefore, these results suggest that the hydrological cycle seems to be the major determinant of zooplankton population dynamics in aquatic semi-arid environments
The Biodiversity of Crustacean Zooplankton in Lake Baiyangdian
白洋淀浮游甲壳动物的生物多样性研究
YI Lei,LIU Cun-qi,xun xiao guang,wang jun xia,zhang yao juan,
易磊,刘存歧,邢晓光,王军霞,张亚娟
水生态学杂志 , 2010,
Abstract: Based on the crustacean zooplankton survey from April to December 2006 in Lake Baiyangdian, 19 Cladocera and 16 Copepoda were recorded, which belong to 9 family and 19 genera. The biodiversity index revealed significant seasonal variation of the crustacean diversity. The dominant Cladocera species in spring, summer and autumn-winter were Moina micrura, Bosmina longirostris, Diaphanosoma leuch, respectively. Cyclopidae strenuus was the dominant Copepoda species in winter-spring while Eucyclopinae macruroides and Thermocyclops tsihokurnsisin summer-autumn. Similarly, species diversity remained high in spring and autumn, but decreased in summer and winter. The highest dividual density was in spring, and the lowest was in winter. According to integrated biological diversity index, water quality of Baiyangdian was mesotrophication.
Method for hatching resting eggs from tropical zooplankton: effects of drying or exposing to low temperatures before incubation
Santangelo, Jayme Magalh？es;Araújo, Luciana Rabelo;Esteves, Francisco de Assis;Manca, Marina;Bozelli, Reinaldo Luiz;
Acta Limnologica Brasiliensia , 2011, DOI: 10.4322/actalb.2011.017
Abstract: aim: in this study we tested the effects of drying or refrigerating (4 °c) cladoceran resting eggs from a tropical aquatic system on the hatching rates and time to hatching, in order to determine what conditions should or should not be applied to break dormancy in tropical cladocerans; methods: resting eggs from two cladoceran species were isolated from the sediment of a coastal lagoon and exposed to drying conditions or low temperatures for four months before incubation under control conditions; results: for moina micrura, drying as well as refrigerating eggs reduced the proportion of eggs hatched, but refrigeration also reduced the time to hatching. for diaphanosoma birgei, refrigeration had no effects either in the proportion of eggs hatched or in time to hatching. drying resting eggs of d. birgei resulted in no hatchlings after re-hydration; conclusions: our results indicate that the pre-exposure of tropical cladoceran resting eggs to low temperatures might not be necessary to break dormancy. additionally, cooling might even reduce the hatching rates of some species. we suggest that tropical cladoceran resting eggs might be incubated soon after sampling the sediment or, if a period for breaking dormancy is required, they should be better kept under dark and at room temperature conditions.
The effect of light on ingestion capacity of Moina mongolica Daday (Cladocera: Moinidae)
光照对蒙古裸腹溞摄食强度的影响
ZHAO Wen,
赵文
生态学报 , 2005,
Abstract: Moina mongolica Daday, which appears to be the only halophilic species of Moina in the old world, distributes from north Africa, across the Middle East and the Central Russia, Aral Sea, Spain. It is a new record of Cladocera in China. Dalian Fisheries University has initiated a saline water research program including its autecology, reproductive biology, feeding ecology and perspective as live food for marine fish larviculture. However, the effect of light on the ingestion capacity is not reported. A di...
Cladocerans (Branchiopoda) of a tropical estuary in Brazil
Paranaguá, M. N;Neumann-Leit？o, S;Nogueira-Paranhos, J. D;Silva, T. A.;Matsumura-Tundisi, T.;
Brazilian Journal of Biology , 2005, DOI: 10.1590/S1519-69842005000100015
Abstract: the study was conducted in the capibaribe river estuary in recife (brazil) to assess the role played by cladocerans in a eutrophic environment. samplings were carried out monthly at 4 fixed stations along the estuary from july 1987 to june 1988. collections were made with a plankton net of 65 micrometers mesh size. six cladocerans species were registered: penilia avirostris, diaphanosoma spinulosum, chydorus barroisi, ceriodaphnia rigaudi, ilyocryptus spinifer, and moina micrura. the most frequent species was moina micrura with 49%. the only true marine species was penilia avirostris, which was registered at station 1 (close to the river mouth), during high and low tide and in the dry season. the cladocera average density decreased from 329 ind.m-3 (august 1987, high tide) to 2 ind.m-3 (march 1988, high tide) due to the high load of organic and chemical pollution received by the estuary. at all stations, d. spinulosum, m. micrura, and c. barroisi occurred with a wide distribution, mainly during the rainy season. c. rigaudi and i. spinifer were rare, occurring only during the rainy season. cladocerans played an important role in the food webs of the plankton community of the capibaribe tropical estuary and the dominance of a few small species indicated a hypereutrophic environment. a high level of disturbance was indicated by the decline in diversity of specialized species and the increase in abundance of opportunistic species like m. micrura.
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