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1.
Proc Biol Sci ; 290(2004): 20230543, 2023 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-37528708

RESUMO

Medusozoa (Cnidaria) are characterized by diverse life cycles, with different semaphoronts (medusa, medusoid, fixed gonophore, polyp) representing the sexual phase and carrying the gametes. Although egg size is often considered a proxy to understand reproductive and developmental traits of medusozoans, understanding of the processes influencing egg size variation in the group under an evolutionary context is still limited. We carried out a comprehensive review of the variation of egg size in Medusozoa to test whether this variation is related to biological/sexual or environmental traits. Egg size presents a strong phylogenetic signal (λ = 0.79, K = 0.67), explaining why closely related species with different reproductive strategies and different individual sizes have similar egg sizes. However, variation in egg size is influenced by the number of eggs, depth and temperature, with larger eggs frequently present in species with few eggs (1-15), in deep-sea species and in cold-water species. Conversely, the production of small eggs among cold-water species of Staurozoa might be associated with the development of a small benthic larvae in this group. Our study reinforces that egg sizes respond to reproductive and environmental traits, although egg size is highly conserved within medusa classes.


Assuntos
Cnidários , Animais , Filogenia , Reprodução , Evolução Biológica , Água
2.
PeerJ ; 9: e11954, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34589293

RESUMO

Cryptic species have been detected across Metazoa, and while no apparent morphological features distinguish them, it should not impede taxonomists from formal descriptions. We accepted this challenge for the jellyfish genus Aurelia, which has a long and confusing taxonomic history. We demonstrate that morphological variability in Aurelia medusae overlaps across very distant geographic localities. Even though some morphological features seem responsible for most of the variation, regional geographic patterns of dissimilarities are lacking. This is further emphasized by morphological differences found when comparing lab-cultured Aurelia coerulea medusae with the diagnostic features in its recent redescription. Previous studies have also highlighted the difficulties in distinguishing Aurelia polyps and ephyrae, and their morphological plasticity. Therefore, mostly based on genetic data, we recognize 28 species of Aurelia, of which seven were already described, 10 are formally described herein, four are resurrected and seven remain undescribed. We present diagnostic genetic characters for all species and designate type materials for newly described and some resurrected species. Recognizing moon jellyfish diversity with formal names is vital for conservation efforts and other studies. This work clarifies the practical implications of molecular genetic data as diagnostic characters, and sheds light on the patterns and processes that generate crypsis.

3.
Zoologia (Curitiba) ; 37: e50834, 2020. mapas, ilus, tab
Artigo em Inglês | VETINDEX | ID: vti-30528

RESUMO

The massive occurrence of jellyfish in several areas of the world is reported annually, but most of the data come from the northern hemisphere and often refer to a restricted group of species that are not in the genus Cassiopea. This study records a massive, clonal and non-native population of Cassiopea and discusses the possible scenarios that resulted in the invasion of the Brazilian coast by these organisms. The results indicate that this jellyfish might have invaded the Brazilian coast multiple times.(AU)


Assuntos
Animais , Cifozoários , Biodiversidade , Espécies Introduzidas
4.
PeerJ ; 7: e7848, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31608180

RESUMO

Hydrozoa medusae undergo blooms and seasonal fluctuations; however the drivers of such fluctuations are unknown. To understand how medusa populations fluctuate in response to seasonal factors such as temperature, salinity, dissolved oxygen, and chlorophyll a, and to enhance our taxonomic knowledge of Hydrozoa in Galveston Bay (TX), we performed frequent plankton sampling from September 2015 to September 2016. We collected 1,321 medusae in 190 sampling days. Using molecular barcoding and morphological analyses we identified 25 species, of which 21 are a first record for Galveston Bay and eight for the Gulf of Mexico. Daily medusa abundance is non-linearly related to temperature, with peak abundance estimated with multivariate regression analysis at approximately 21C. The role that temperature plays in driving medusa abundance has implications for future climate change scenarios, given that temperature in the Gulf of Mexico is expected to rise 4 °C by the end of the century. We also show that the biodiversity of the Galveston Bay and the Gulf of Mexico is underestimated and that molecular barcoding is an important and efficient tool to identify large number of medusae. We conclude that dense plankton sampling is necessary to capture both diversity and abundance of planktonic medusae.

5.
Zool Stud ; 58: e37, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31966338

RESUMO

This study provides the first observation that umbrellar tissue can lead to the formation of virtually all body structures in jellyfish of the order Rhizostomeae. The regeneration process was observed in two specimens of the upside-down jellyfish Cassiopea xamachana Bigelow, 1892, one housed at the Vienna Zoo, Austria and the other in a laboratory at the University of São Paulo, Brazil. The process was triggered by an injury and ended with the formation of two new sets of body structures. Our observation offers evidence that C. xamachana has a hidden regenerative capacity exceeding that previously recorded.

6.
Braz. j. biol ; Braz. j. biol;77(4): 665-672, Nov. 2017. graf
Artigo em Inglês | LILACS | ID: biblio-888809

RESUMO

Abstract The freshwater cnidarian Craspedacusta sowerbii Lankester 1880, has invaded lakes and ponds as well as artificial water bodies throughout the world. The first record in Uruguay corresponding to the jellyfish was made in 1961 in two artificial fountains, with no mention of the polyp form. Although local reports of other related polyp species have been made, information on the benthic form of C. sowerbii is lacking. Here we report the finding of live frustules, solitary individuals, medusae and colonies from a natural lagoon in August 2010, allowing us to observe the morphology and behavior of the polyp stage in captivity. In addition, molecular identification and remarks on the potencial path of introduction are presented. This is the first record in Uruguay of both polyp and medusa stages of C. sowerbii in a natural water body, Del Medio Lagoon (Dpto. de Florida), Uruguay.


Resumo O cnidário Craspedacusta sowerbii Lankester 1880 de água doce, tem invadido lagos e lagoas, bem como corpos de água artificiais em todo o mundo. O primeiro registro no Uruguai correspondente à água-viva foi feita em 1961, em duas fontes artificiais, sem mencionar a forma de pólipo. Embora existem relatórios locais de pólipos de outras espécies relacionados, informações sobre a forma bentônica de C. sowerbii ainda são escassas. Neste trabalho se relata a ocorrência de frústulas vivas, de indivíduos solitários, medusas e colônias de uma lagoa natural, em agosto de 2010, onde foi possível observar a morfologia e comportamento da fase de pólipo em cativeiro. Além disso, identificação molecular e observações sobre a potencial via de entrada da espécies são apresentados. Este é o primeiro registro no Uruguai de ambos estágios de vida de C. sowerbii em um corpo de água natural, Lagoa Del Medio (Dpto. De Florida), Uruguai.


Assuntos
Animais , Hidrozoários/fisiologia , Distribuição Animal , Estágios do Ciclo de Vida , Uruguai , Hidrozoários/crescimento & desenvolvimento , Espécies Introduzidas
7.
Braz. J. Biol. ; 77(4): 665-672, Nov. 2017. ilus, mapas
Artigo em Inglês | VETINDEX | ID: vti-20414

RESUMO

The freshwater cnidarian Craspedacusta sowerbii Lankester 1880, has invaded lakes and ponds as well as artificial water bodies throughout the world. The first record in Uruguay corresponding to the jellyfish was made in 1961 in two artificial fountains, with no mention of the polyp form. Although local reports of other related polyp species have been made, information on the benthic form of C. sowerbii is lacking. Here we report the finding of live frustules, solitary individuals, medusae and colonies from a natural lagoon in August 2010, allowing us to observe the morphology and behavior of the polyp stage in captivity. In addition, molecular identification and remarks on the potencial path of introduction are presented. This is the first record in Uruguay of both polyp and medusa stages of C. sowerbii in a natural water body, Del Medio Lagoon (Dpto. de Florida), Uruguay.(AU)


O cnidário Craspedacusta sowerbii Lankester 1880 de água doce, tem invadido lagos e lagoas, bem como corpos de água artificiais em todo o mundo. O primeiro registro no Uruguai correspondente à água-viva foi feita em 1961, em duas fontes artificiais, sem mencionar a forma de pólipo. Embora existem relatórios locais de pólipos de outras espécies relacionados, informações sobre a forma bentônica de C. sowerbii ainda são escassas. Neste trabalho se relata a ocorrência de frústulas vivas, de indivíduos solitários, medusas e colônias de uma lagoa natural, em agosto de 2010, onde foi possível observar a morfologia e comportamento da fase de pólipo em cativeiro. Além disso, identificação molecular e observações sobre a potencial via de entrada da espécies são apresentados. Este é o primeiro registro no Uruguai de ambos estágios de vida de C. sowerbii em um corpo de água natural, Lagoa Del Medio (Dpto. De Florida), Uruguai.(AU)

9.
Rev. biol. trop ; Rev. biol. trop;60(4): 1721-1729, Dec. 2012. graf, tab
Artigo em Espanhol | LILACS | ID: lil-662243

RESUMO

The cannonball jellyfish Stomolophus meleagris is regarded as a fishery resource with high commercial value, but with scarce biological information. With the aim to generate preliminary information on reproductive aspects, the present study analyzes its fecundity, based on the estimated number of vitellogenic oocytes in the gonad; in addition, we evaluated its relationship with the jellyfish body length, diameter and wet weight; and we established the relationship of the gonadosomatic index (IGS) with the jellyfish diameter and length. For this, a total of 30 specimens were collected, measured and weighed in a monthly basis, in Las Guásimas lagoon from January to May 2006. In order to estimate the gonad volume, 60 mature females were analyzed and their gonads were extracted and stained with hematoxylin-eosin. Gonad images from histological preparations were analyzed and the number of vitellogenic and previtellogenic oocytes obtained. We used catch data from The Guásimas for population recruitment analysis, that was estimated with FISAT II. Among results, we found that fecundity increased with jellyfish length, diameter and total wet weight. The lower fecundity rates occured on February and the highest during May (11 873 071 and 37 528 197 millions of vitellogenic oocytes per gonad, respectively). The IGS increased with length and diameter of the specimens, at its maximum value of 3.7% was observed in May. A continuous production of previtellogenic oocytes were observed during the full collection period. The maximum recruitment was observed in July and November (37.50% and 28.01% respectively). The high fecundity observed in S. meleagris, suggests a high population reproductive potential that may support the possibility of an important fishery consolidation on this jellyfish.


La medusa Stomolophus meleagris es considerada un recurso pesquero de alto valor comercial. Debido a la relevancia de conocer aspectos de importancia biológica actualmente desconocidos, el presente trabajo analiza la fecundidad con base en la estimación del número de ovocitos vitelogénicos en la gónada; su relación con la longitud, diámetro y peso húmedo; y la relación del índice gonadosomático (IGS) con su diámetro y longitud. De enero a mayo 2006 se recolectaron 30 ejemplares mensuales que fueron medidos y pesados, de los cuales se analizaron 60 hembras maduras para calcular el volumen de sus gónadas. Se extrajeron las gónadas, se tiñeron con hematoxilina-eosina y se seleccionaron las hembras con madurez gonadal. Mediante la digitalización de imágenes se estimó el número de ovocitos vitelogénicos y previtelogénicos. Se emplearon datos de captura en Las Guásimas para el análisis de reclutamiento poblacional, estimado con FISAT II. La fecundidad se incrementó con la longitud, el diámetro y el peso húmedo total. La menor fecundidad se observó en febrero y la mayor en mayo (11 873 071 y 37 528 197 millones de ovocitos vitelogénico por gónada, respectivamente). El IGS se incrementó con la longitud y diámetro de los ejemplares, con su máximo en mayo de 3.7%. Se observó una producción continua de ovocitos previtelogénicos en todo el periodo de recolecta. El máximo reclutamiento se observó en julio y noviembre (37.50% y 28.01% respectivamente). La alta fecundidad encontrada en S. meleagris sugiere un alto potencial reproductivo para la población y sustenta la posibilidad de la consolidación de una importante pesquería de esta medusa.


Assuntos
Animais , Feminino , Gônadas/anatomia & histologia , Oócitos , Cifozoários/fisiologia , Fertilidade/fisiologia , Gônadas/citologia , México , Estações do Ano , Cifozoários/anatomia & histologia
10.
Medicina (B.Aires) ; Medicina (B.Aires);72(5): 380-388, oct. 2012. ilus
Artigo em Espanhol | BINACIS | ID: bin-129305

RESUMO

La picadura de la medusa o agua viva Olindia sambaquiensis es de ocurrencia frecuente en las playas de la costa de la provincia de Buenos Aires. Se notifican entre quinientas y mil picaduras de medusas por temporada en la localidad balnearia de Monte Hermoso, al sur de la provincia de Buenos Aires. El daño cutáneo que provoca por su elevada acción urticante plantea un serio inconveniente para el desarrollo del turismo. Durante el mes de enero de 1998, en la localidad de Monte Hermoso se reunieron un total de 49 casos que fueron examinados dentro de la hora posterior a la picadura. Veintiocho eran de sexo masculino (57.1%). La edad promedio fue de 16 ± 4.1 (rango 5-80). El 54% presentó lesiones eritemato-edematosas de configuración lineal, el 28% presentó lesiones predominantemente eritematosas y el 18% presentó placas eritemato-edematosas. En el 73% de los casos las lesiones se localizaron en miembros inferiores. Hemos redefinido la lesión cutánea producida por la medusa O. sambaquiensis, su evolución, sus dimensiones y localizaciones más frecuentes. Además, se ha tipificado y cuantificado el dolor que produce, y otros signos y síntomas que acompañan a la picadura en la hora posterior, a las primeras 24 horas y a los 30 días. Describimos las conductas terapéuticas utilizadas en nuestra costa, evaluamos la efectividad de algunas de ellas en el control del dolor y finalmente proponemos un esquema terapéutico para dicha picadura.(AU)


Olindias sambaquiensis jellyfish sting occurs frequently in Buenos Aires province coast beaches. Among five hundred and one thousand stings by jellyfish are reported each season at Monte Hermoso, a beach village in the South of Buenos Aires province. The skin damage provoked because of its highly irritant effect poses a serious issue related to tourism development. A total number of 49 cases that were examined during the first hour after the sting were enrolled in Monte Hermoso during January 1998. Twenty eight were males (57.1%). The average age was 16 ± 4.1 (range 5-80). Of them, 54% showed linear erythema-edematous lesions, 28% showed predominantly erythematous lesions, and in 18% the injuries were erythema-edematous plaques. In 73% of the cases the lesions were located in lower limbs. We had hereby redefined cutaneous lesions produced by O. sambaquiensis, its evolution, its dimensions and most frequent localizations. Besides, it has been typified and quantified the pain it provokes and other signs and symptoms that go with the sting during the posterior hour, during the first 24 hours, and after 30 days. We described the therapeutic conducts used in our coasts and we assessed the effectiveness of some of them in pain control, and finally we propose a therapeutic scheme for this sting.(AU)


Assuntos
Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Mordeduras e Picadas/complicações , Venenos de Cnidários/intoxicação , Edema/etiologia , Eritema/etiologia , Hidrozoários , Dor/etiologia , Mordeduras e Picadas/terapia , Manejo da Dor , Estudos Prospectivos , Urticária/etiologia
11.
Medicina (B.Aires) ; Medicina (B.Aires);72(5): 380-388, oct. 2012. ilus
Artigo em Espanhol | LILACS | ID: lil-657533

RESUMO

La picadura de la medusa o agua viva Olindia sambaquiensis es de ocurrencia frecuente en las playas de la costa de la provincia de Buenos Aires. Se notifican entre quinientas y mil picaduras de medusas por temporada en la localidad balnearia de Monte Hermoso, al sur de la provincia de Buenos Aires. El daño cutáneo que provoca por su elevada acción urticante plantea un serio inconveniente para el desarrollo del turismo. Durante el mes de enero de 1998, en la localidad de Monte Hermoso se reunieron un total de 49 casos que fueron examinados dentro de la hora posterior a la picadura. Veintiocho eran de sexo masculino (57.1%). La edad promedio fue de 16 ± 4.1 (rango 5-80). El 54% presentó lesiones eritemato-edematosas de configuración lineal, el 28% presentó lesiones predominantemente eritematosas y el 18% presentó placas eritemato-edematosas. En el 73% de los casos las lesiones se localizaron en miembros inferiores. Hemos redefinido la lesión cutánea producida por la medusa O. sambaquiensis, su evolución, sus dimensiones y localizaciones más frecuentes. Además, se ha tipificado y cuantificado el dolor que produce, y otros signos y síntomas que acompañan a la picadura en la hora posterior, a las primeras 24 horas y a los 30 días. Describimos las conductas terapéuticas utilizadas en nuestra costa, evaluamos la efectividad de algunas de ellas en el control del dolor y finalmente proponemos un esquema terapéutico para dicha picadura.


Olindias sambaquiensis jellyfish sting occurs frequently in Buenos Aires province coast beaches. Among five hundred and one thousand stings by jellyfish are reported each season at Monte Hermoso, a beach village in the South of Buenos Aires province. The skin damage provoked because of its highly irritant effect poses a serious issue related to tourism development. A total number of 49 cases that were examined during the first hour after the sting were enrolled in Monte Hermoso during January 1998. Twenty eight were males (57.1%). The average age was 16 ± 4.1 (range 5-80). Of them, 54% showed linear erythema-edematous lesions, 28% showed predominantly erythematous lesions, and in 18% the injuries were erythema-edematous plaques. In 73% of the cases the lesions were located in lower limbs. We had hereby redefined cutaneous lesions produced by O. sambaquiensis, its evolution, its dimensions and most frequent localizations. Besides, it has been typified and quantified the pain it provokes and other signs and symptoms that go with the sting during the posterior hour, during the first 24 hours, and after 30 days. We described the therapeutic conducts used in our coasts and we assessed the effectiveness of some of them in pain control, and finally we propose a therapeutic scheme for this sting.


Assuntos
Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Mordeduras e Picadas/complicações , Venenos de Cnidários/intoxicação , Edema/etiologia , Eritema/etiologia , Hidrozoários , Dor/etiologia , Mordeduras e Picadas/terapia , Manejo da Dor , Estudos Prospectivos , Urticária/etiologia
12.
Junguiana ; 30(1): 53-57, jan.-jun. 2012.
Artigo em Português | Index Psicologia - Periódicos | ID: psi-53094

RESUMO

A autora propõe uma digressão sobre como a integração de polaridades simbólicas para o complexo do eu se forja, comparando essa integração ao conceito qualia, da neurociência. A integração ocorre com a mobilização de grande carga emocional e se dá pela consciência reflexiva que tem um caráter pós-patriarcal e qualifica esse padrão de consciência como dialogal. Propõe também que as polaridades simbólicas não estruturadas permanecem no reino da sombra como instâncias da própria identidade e passam a funcionar como inimigos de si mesmo, provocando a formação de anticorpos, que qualifica como anticorpos psíquicos. Conclui que o processo de individuação é o gerador da maior de todas as diversidades (AU)


The author proposes a digression on how the integration of polarities for the symbolic complex of Ego is forged, comparing to the concept integration of Qualia Neuroscience. The integration occurs through reflexive counsciousness which has a post-patriarcal character and qualifies this pattern of counsciousness as dialogical. It also proposes that the polarities symbolic unstructured remains in the realm of the shadow as instances of their own identity and operate as enemies of himself, causing the formation of psyche antibodies. The author concludes that the process of individuation is the generator of the greatest of all diversities (AU)


Assuntos
Conhecimento , Psicologia do Self , Consciência , Individuação
13.
Rev. biol. trop ; Rev. biol. trop;58(1): 119-130, mar. 2010. graf, tab
Artigo em Espanhol | LILACS | ID: lil-637812

RESUMO

Lipid variation in oocytes of the jellyfish Stomolophus meleagris (Scyphozoa: Rhizostomeae) from Las Guasimas Lagoon, Mexico, during gonadal development. The jellyfish Stomolophus meleagris has potential for commercial exploitation but there is little information on their reproductive biology. This paper seeks to evaluate some biochemical and demographic characteristics of the species. Samples were taken monthly during 2005 and 2006. Jellyfish collected in 2005 were used to describe the characteristics and quantity of oocyte triglycerides and phospholipids with the Sudan black technique, and to ascertain the degree of gonadal development and sex ratio by the hematoxylin-eosin technique. The 2006 jellyfish were used to determine the size at first maturity and protein and total lipids contents. Four stages of development in both sexes were determined, with a continuous gamete development. The highest percentage of mature organisms was recorded in April. The proportion of sexes was 0.7:1.3. We found higher concentrations of triglycerides than phospholipids in the cytoplasm. There was a positive correlation between triglycerides and the diameter of the oocyte. The size at first maturity for both sexes was 105mm. The highest protein and lipids contents were obtained in April and March respectively. Rev. Biol. Trop. 58 (1): 119-130. Epub 2010 March 01.


La medusa S. meleagris, ha mostrado potencial de explotación pero hay escasa información sobre su biología reproductiva. El presente trabajo pretende conocer el contenido de los triglicéridos y fosfolípidos en los ovocitos durante el desarrollo gonadal, así como la proporción de sexos, talla de primera madurez y la concentración de proteínas y lípidos totales en la medusa. Se realizaron muestreos mensuales durante 2005 y 2006. A las medusas recolectadas en 2005, se les aplicó la técnica del sudán negro, para describir las características del ovocito y la cantidad triglicéridos y fosfolípidos y la técnica de hematoxilina-eosina para conocer el grado de desarrollo gonádico y la proporción de sexos. Las medusas del 2006 se emplearon para determinar la talla de primera madurez y el contenido de proteínas y lípidos totales. Se observaron cuatro fases de desarrollo en ambos sexos, con un desarrollo gamético continúo. El mayor porcentaje de organismos maduros se registró en abril. La proporción de sexos fue de 0.7:1.3. Se encontró mayor concentración de triglicéridos que de fosfolípidos en el citoplasma. Se obtuvo una correlación positiva entre triglicéridos y el diámetro del ovocito. La talla de primera madurez para ambos sexos fue de 105 mm. El mayor contenido de proteínas se obtuvo en abril y para lípidos en marzo.


Assuntos
Animais , Feminino , Masculino , Gônadas/crescimento & desenvolvimento , Oócitos/química , Fosfolipídeos/análise , Cifozoários/química , Maturidade Sexual/fisiologia , Triglicerídeos/análise , México , Oócitos/crescimento & desenvolvimento , Estações do Ano , Razão de Masculinidade , Cifozoários/classificação , Cifozoários/fisiologia
14.
Biota neotrop. (Online, Ed. port.) ; 7(1)2007. ilus, mapas, tab
Artigo em Inglês | LILACS | ID: lil-459172

RESUMO

The occurrence of the freshwater jellyfish Craspedacusta sowerbii (=sowerbyi) Lankester, 1880 was recorded in April 2006 in the Lagoa Misteriosa water body, a calcareous lake (doline) in Mato Grosso do Sul State, Brazil. Only Rotifera composed the zooplankton community was composed only of Rotifera and the environment was meso-eutrophic system. The nomenclature of C. sowerbii is discussed with regard to the use of the correct spelling and an alternative one. The distributions of C. sowerbii in Brazil include eight states and in South America the distribution includes four countries.


A ocorrência da água-viva de água doce Craspedacusta sowerbii (=sowerbyi) Lankester, 1880 foi registrada em abril de 2006, na lagoa Misteriosa, um lago calcário (dolina) no estado do Mato Grosso do Sul, Brasil. A comunidade zooplanctônica foi composta apenas por Rotifera e a qualidade da água do sistema apresentou uma classificação de meso-eutrófico. A nomenclatura foi discutida quanto às formas usuais de grafia do nome e proposta uma alternativa. A distribuição da C. sowerbii no Brasil inclui oito estados e na América do Sul a distribuição apontou quatro países onde a espécie foi registrada.


Assuntos
Cnidários/classificação , Fauna Aquática/análise , Fauna Aquática/classificação , Hidrozoários/anatomia & histologia , Hidrozoários/classificação , Lagos/análise , Zooplâncton/classificação
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