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Crecimiento y ciclo reproductivo de Polymesoda radiata (Bivalvia:Corbiculidae) en Costa Rica
Ruiz Campos,Eleazar; Cabrera Pe?a,Jorge; Cruz,Rafael A.; Palacios,José A.;
Revista de Biología Tropical , 1998,
Abstract: a population of green clam, polymesoda radiata was sampled from august 1992 through july 1993 in bebedero river, guanacaste, costa rica (n= 978) for demographic data. mean values (followed by ranges) were: shell length 32.29 ±7.63 mm (6.9-44.10 mm). the mean total weight was 11.13 ±5.71 g (0.4-23.98 g). data analysis showed a isometric relationship between length and total weight, represented by the equation : pt=2.07 x 10-4 lt3.01 (r=0.987, p < 0.01). von bertalanffy's equations were: for length lt=45 [1 - e{-1(t+0.06) (05/2 ) sen 2 ((t-065}] and for weight pt= 26.53 (1- e [-1 (t + 0.06)])3 . the growth rate for total length was 2.25 ±0.66 mm/month for the first year (0.83 ±0.24 the second year and 0.26 ±0.1 for other months). individuals become sexually mature throughout the year. the mean sex ratio was 1.00 male : 0.61 females. spawning suggested that minimum size at sexual maturity was 7.80 mm of lt. the largest number of ripe individuals was found in the dry season. spawning peaks were in december and march. histologically this is a dioecious bivalve with stable gonocorism.
Crecimiento y ciclo reproductivo de Polymesoda radiata (Bivalvia:Corbiculidae) en Costa Rica  [cached]
Eleazar Ruiz Campos,Jorge Cabrera Pe?a,Rafael A. Cruz,José A. Palacios
Revista de Biología Tropical , 1998,
Abstract: Se determinó el crecimiento, biometría, desarrollo gonádico, ciclo reproductivo y talla mínima reproductiva en Polymesoda radiata en el río Bebedero, Guanacaste Costa Rica, entre agosto 1992 y julio 1993. El promedio de la longitud total fue 32.29 ±7.63 mm (ámbito entre 6.90 to 44.10 mm). El peso total fue 11.13 ±5.71 g (ámbito entre 0.4 to 23.98 g). La relación Lt-Pt determinó que el crecimiento es de tipo isométrico y se rige por la ecuación Pt= 2.07 x 10-4 Lt3.01 (r=0.987, p 0.01). La ecuación generalizada de von Bertalanffy se rige para Lt por Lt= 45 [1 - e{-1(t+0.06) (05/2 ) sen 2 ((t-065}] y para peso total por Pt= 26.53 (1- e [-1 (t + 0.06)] )3. La tasa de crecimiento para Lt fue de 2.25 ±0.66 mm/mes para el primer a o, 0.83 ±0.24 mm/mes para el segundo a o y 0.26 ±0.1 mm/mes para el resto de los meses. Durante todo el a o se encontraron individuos en las diferentes etapas reproductivas. La proporción sexual para el periodo de estudio fue de 1.00 macho:0.61 hembras. La talla a la que se distinguen células sexuales tanto para machos como hembras fue de 6.62 mm y se establece como talla mínima reproductiva 7.80 mm, ya que a partir de ésta se observaron individuos desovados. La mayor actividad de desove se observó durante la época seca con dos picos máximos de desove al a o, uno en diciembre y el otro en marzo. El análisis histológico determinó que la especie es dioica con un bajo porcentaje de hermafroditismo en la población (2.15 %). A population of green clam, Polymesoda radiata was sampled from August 1992 through July 1993 in Bebedero river, Guanacaste, Costa Rica (n= 978) for demographic data. Mean values (followed by ranges) were: shell length 32.29 ±7.63 mm (6.9-44.10 mm). The mean total weight was 11.13 ±5.71 g (0.4-23.98 g). Data analysis showed a isometric relationship between length and total weight, represented by the equation : Pt=2.07 x 10-4 Lt3.01 (r=0.987, p < 0.01). Von Bertalanffy's equations were: for length Lt=45 [1 - e{-1(t+0.06) (05/2 ) sen 2 ((t-065}] and for weight Pt= 26.53 (1- e [-1 (t + 0.06)])3 . The growth rate for total length was 2.25 ±0.66 mm/month for the first year (0.83 ±0.24 the second year and 0.26 ±0.1 for other months). Individuals become sexually mature throughout the year. The mean sex ratio was 1.00 male : 0.61 females. Spawning suggested that minimum size at sexual maturity was 7.80 mm of Lt. The largest number of ripe individuals was found in the dry season. Spawning peaks were in December and March. Histologically this is a dioecious bivalve with stable gonocorism.
Distribución, abundancia y aspectos biológicos de la almeja Polymesoda solida Phillippi, 1846 (Bivalvia: Corbiculidae) en la Isla De Salamanca, Caribe Colombiano  [cached]
Hoz María Virginia de la,Campos Néstor,Blanco Jacobo
Acta Biológica Colombiana , 2006,
Abstract: Con el propósito de evaluar el estado actual de la almeja estuarina Polymesoda solida como recurso ecológico y pesquero, se estudiaron diversos aspectos de la población en el sector occidental de la isla de Salamanca, en el Caribe colombiano. El muestreo se llevó a cabo mensualmente en cuatro ciénagas interconectadas de este Parque Natural, tres de ellas sometidas a explotación, entre abril y noviembre de 2004. Se estimó la densidad por metro cuadrado y se efectuaron mediciones de largo, alto y espesor de las conchas para obtener las distribuciones de tallas y relaciones morfométricas. Para conocer la condición física de los animales se estimaron índices de condición con base en los pesos de concha y partes blandas y se calculó el porcentaje de materia orgánica en los tejidos blandos. El estado reproductivo se determinó a partir de observaciones en fresco del material gonadal. Se llevaron a cabo análisis de correlación y de regresión múltiple para conocer el grado de influencia de diversas variables ambientales sobre aspectos biológicos de la almeja. Las condiciones ambientales en las ciénagas variaron en función de la distancia al río Magdalena y al mar, mostrando para ciertas variables un patrón marcadamente estacional, obedeciendo a las épocas climáticas. Se destacaron las diferencias en las características de P. solida entre sitios de muestreo, presentándose rangos de tallas, densidades, índices de condición y tipo de sustrato muy característico para cada ciénaga. La densidad varió inversamente con la talla, las longitudes de los ejemplares oscilaron entre 9,8 mm y 50 mm, predominando el rango de 25-30 mm. Se encontraron reclutas (<5mm) ocasionalmente en orillas arenosas de algunos sectores. Las fluctuaciones en el índice de condición de los individuos se asociaron a los cambios en el estado fisiológico a lo largo del tiempo, muy dependientes del estado reproductivo. También se observaron diferencias entre ciénagas, se alándose la importancia de la salinidad, pH y transparencia del agua en las características biológicas de la población y por lo tanto se corroboró la importancia del régimen hídrico en su regulación. La mejor condición física de P. solida estuvo directamente relacionada con la menor salinidad a nivel espacial y temporal. Esto permitió establecer que la almeja en la zona de estudio posiblemente se adapta mejor a salinidades muy bajas en relación con lo encontrado en otros lugares del mundo. La gran variabilidad en las distribuciones de tallas y en la densidad de individuos se asoció a la heterogeneidad de un sistema estuarino altamente
Condición somática de la almeja Polymesoda solida (Veneroidea: Corbiculidae) durante el periodo lluvioso, enel Parque Natural Isla de Salamanca, Caribe colombiano
De La Hoz Aristizábal,María Virginia;
Revista de Biología Tropical , 2010,
Abstract: somatic condition of the clam polymesoda solida (veneroidea: corbiculidae) in the rainy season of the salamanca island natural park, colombian caribbean. the estuarine clam polymesoda solida is the main fishery resource in the salamanca island natural park. i sampled the clam in three interconnected lagoons (poza verde, el torno and atascosa) during the rainy period (april to november 2004). sixty individuals were monthly collected by hand on each lagoon; 30 to analyze two condition indexes (relationship between body and shell weight and between soft dry and wet weight), yield (meat percentage) and length-weight relationships. maturity of female gonad smears was assessed on the remaining individuals. measures of salinity, temperature, ph, dissolved oxygen, transparency and depth, were also taken at the collection places. increases of the condition indexes occurred when the magdalena river showed some decreases in its level, especially at poza verde and el torno. the condition indexes were higher at 27-33mm, (range where maturity size was reached). clams from poza verde, the lagoon nearest to the magdalena river, had the highest values in condition indexes, yield, fresh weight and maturity frequency. yield was directly correlated to the condition indexes and sexual maturity. the condition index (body weight/shell weight) showed a highest multiple regression coefficient with salinity, ph and transparency (r2=74%), indicating the relevance of the hydrological regime in the regulation of the condition of the organisms. p. solida seems to be more adapted to the lowest salinities of the system (0.0-0.4), corresponding to poza verde, where the influence of the magdalena river is more direct and steady. additionally, differences found between sites in the assessed variables, emphasize the importance of considering spatial heterogeneity of this kind of lagoon estuaries, and should be taken into account for future fisheries management in the rainy period and conservation of p
Condición somática de la almeja Polymesoda solida (Veneroidea: Corbiculidae) durante el periodo lluvioso, enel Parque Natural Isla de Salamanca, Caribe colombiano
María Virginia De La Hoz Aristizábal
Revista de Biología Tropical , 2010,
Abstract: Se evaluó la condición somática de la almeja Polymesoda solida en tres lagunas del Parque Isla de Salamanca (abril a noviembre de 2004), durante el periodo lluvioso. En 60 individuos por laguna, se analizaron mensualmente índices de condición, rendimiento, relación talla-peso y madurez gonadal en fresco. También se midió salinidad, temperatura, pH, oxígeno disuelto, transparencia y profundidad del agua. Los mayores índices de condición coincidieron con descensos en el nivel del río Magdalena, especialmente en Poza Verde y El Torno. Estos índices fueron más altos en tallas entre 27mm y 33mm, donde también se ubicó la talla media de madurez sexual. En Poza Verde, laguna con mayor influencia del río, se presentaron los mayores índices de condición, rendimiento, peso húmedo y frecuencia de madurez, revelando una mejor condición de los organismos. El índice de condición (peso cuerpo/ peso concha) presentó mayor coeficiente de regresión múltiple con la salinidad, pH y transparencia, sugiriendo la importancia del régimen hidrológico en su regulación. Las diferencias espaciales en las variables evaluadas, resaltan la necesidad de tener en cuenta la heterogeneidad de este tipo de estuarios para la conservación y manejo adecuado de la pesquería de P. solida. Somatic condition of the clam Polymesoda solida (Veneroidea: Corbiculidae) in the rainy season of the Salamanca Island Natural Park, Colombian Caribbean. The estuarine clam Polymesoda solida is the main fishery resource in the Salamanca Island Natural Park. I sampled the clam in three interconnected lagoons (Poza Verde, El Torno and Atascosa) during the rainy period (April to November 2004). Sixty individuals were monthly collected by hand on each lagoon; 30 to analyze two condition indexes (relationship between body and shell weight and between soft dry and wet weight), yield (meat percentage) and length-weight relationships. Maturity of female gonad smears was assessed on the remaining individuals. Measures of salinity, temperature, pH, dissolved oxygen, transparency and depth, were also taken at the collection places. Increases of the condition indexes occurred when the Magdalena River showed some decreases in its level, especially at Poza Verde and El Torno. The condition indexes were higher at 27-33mm, (range where maturity size was reached). Clams from Poza Verde, the lagoon nearest to the Magdalena River, had the highest values in condition indexes, yield, fresh weight and maturity frequency. Yield was directly correlated to the condition indexes and sexual maturity. The condition index (body weight/sh
PRIMER REGISTRO EN COLOMBIA DE CORBICULA FLUMINEA (MOLLUSCA: BIVALVIA: CORBICULIDAE), UNA ESPECIE INVASOR
De La Hoz Aristizábal,Maria V.;
Boletín de Investigaciones Marinas y Costeras - INVEMAR , 2008,
Abstract: the bivalve corbicula fluminea müller is recorded for the first time in colombia, in the national park isla de salamanca. this protected area includes freshwater channels and mixohaline lagoons influenced by waters of both the magdalena river and the caribbean sea. this exotic bivalve occurs locally in freshwater channels close to the magdalena river as well as in the latter, whereas another corbiculid native species, polymesoda solida, is commonly found in the mixohaline lagoons. densities of c. fluminea ranged from 10 to 100 ind/m2 along with low numbers of p. solida. lengths ranged form 10 to 43 mm in a predominant muddy substrate. local fishermen have stated that c. fluminea was established approximately in 1992; this clam is being artisanally exploited for human consumption along with p. solida, although fishery is mainly focused on the latter, due to its larger size.
Phylogeny and androgenesis in the invasive Corbicula clams (Bivalvia, Corbiculidae) in Western Europe
Lise-Marie Pigneur, Jonathan Marescaux, Kathleen Roland, Emilie Etoundi, Jean-Pierre Descy, Karine Van Doninck
BMC Evolutionary Biology , 2011, DOI: 10.1186/1471-2148-11-147
Abstract: There are three Corbicula morphotypes in Western Europe associated to three mitochondrial lineages and three genotypes. Form R shares the same COI haplotype as the American form A and the Japanese C. leana. Form S and the American form C have the same haplotype, although their morphologies seem divergent. The European form Rlc belongs to the same mitochondrial lineage as both the American form B and the Asian C. fluminea.Interestingly, within each haplotype/genotype or lineage, no genetic diversity was found although their invasive success is high. Moreover, we detected rare mismatches between mtDNA and nrDNA/morphology, indicative of androgenesis and mitochondrial capture between form R and form S and therefore challenging the phylogenetic relatedness and the species status within this genus. The global phylogenetic analysis revealed that the sexual Corbicula lineages seem restricted to the native areas while their androgenetic relatives are widespread and highly invasive.We clarified the discrepancies and incongruent results found in the literature about the European morphotypes of Corbicula and associated mitochondrial lineages. The three West European morphotypes belong to three distinct nuclear and mitochondrial lineages. However mitochondrial capture occurs in sympatric populations of forms R and S. The species status of the morphotypes therefore remains doubtful. Moreover the androgenetic lineages seem widely distributed compared to their sexual relatives, suggesting that androgenesis and invasive success may be linked in the genus Corbicula.The clams of the genus Corbicula are successful fresh and brackish water invaders considered 'r'-strategists, with rapid maturation, high fecundity, and high dispersal [1-3]. These bivalves are benthic filter-feeders which can reduce phytoplankton density [4-6], compete with native species [7,8] and damage industrial cooling systems [9]. The genus Corbicula is of particular interest both because of its diverse reproductiv
Contribui??o à conquiliometria de Neocorbicula limosa (Maton, 1811) (Bivalvia, Corbiculidae)
Garces, Liana Mercedes Maria Pares;Mansur, Maria Cristina Dreher;Thomé, José Willibaldo;
Revista Brasileira de Zoologia , 1989, DOI: 10.1590/S0101-81751989000300010
Abstract: the correlations among the total length, pré-umbonal length, width and height of the shell of neocorbicula limosa (maton, 1811), based on the examination of 100 shells from the rio guaíba basin are established. the radio index among these measures was calculated and the maximum, intermediary and minimum values are presented. as a result of data analysis it was pointed out that the relationship among the measures are positive and there is no allometry. it is also suggested that the proportion indexes could be used as helpful diagnostic character in conchologic studies.
Analysis of Condition Index in Polymesoda expansa (Mousson 1849)
Azimah Abdul Rahim,Mohd Hanafi Idris,Abu Hena Mustafa Kamal,S.K. Wong
Pakistan Journal of Biological Sciences , 2012,
Abstract: The Condition Index (CI) is a method to measure overall health of fish and that has been applied to estimate the effect that different environmental factors have on clam meat quality. The CI of local mangrove clam Polymesoda expansa in Kelulit, Miri Sarawak was determined from October 2010 to November 2011. Condition index that is generally used to characterize the physiological activity of organisms, varied from 1.8% in December 2010 to 3.4% in October 2011, with low values observed during the spawning period. The clam attained their best condition in quality of flesh weight during July-October. In present study, the CI showed a clear relationship with the reproductive cycle of P. expansa. However, no significant correlation (p>0.05) was found between CI and the different physicochemical parameter of seawater. The data presented is necessary for developing sustainable management strategies and broodstock selection for the species which is crucial in aquaculture development.
GENETIC VARIABILITY OF POLYMESODA EROSA POPULATION IN THE SEGARA ANAKAN CILACAP  [cached]
AGUS NURYANTO,AGUS HERY SUSANTO
BIOTROPIA : the Southeast Asian Journal of Tropical Biology , 2010,
Abstract: Mud clams, Polymesoda erosa, in the Segara Anakan Cilacap are highly exploited by the local communities for daily consumption. This is presumed causing population decline and potentially causing loss of genetic diversity. Genetic diversity level within population can be obtained by population genetic study using molecular marker such as randomly amplified polymorphic DNA (RAPD). Here we amplified RAPD marker using ten arbitrary primers to assess genetic diversity of P. erosa population in the Segara Anakan Cilacap to provide genetic data for its sustainable use. The results proved that the use of RAPD marker has high polymorphisms. The mud clam population also showed a high level of heterozygosity and genetic diversity. This has important implication for the management plan towards sustainable use of P. erosa in the Segara Anakan Cilacap.
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