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Las comunidades de helmintos del lenguado (Symphurus plagiusa) en la costa de Campeche, México The helminth communities of tonguefish (Symphurus plagiusa) of the Campeche coast, Mexico  [cached]
Abril Rodríguez-González,Víctor M. Vidal-Martínez
Revista mexicana de biodiversidad , 2008,
Abstract: Se caracterizaron las comunidades componentes e infracomunidades de helmintos de Symphurus plagiusa en 37 puntos de muestreo de mayo a septiembre de 2003 en la costa de Campeche. Además, se exploraron posibles asociaciones estadísticas entre la abundancia de cada especie y los parámetros ambientales (salinidad, oxígeno, volumen de descarga de agua de ríos) mediante análisis de redundancia (RDA). Se examinaron 531 hospederos, cuyas comunidades componentes e infracomunidades fueron pobres en número de especies (máximos: 8 y 3 ± 1 respectivamente), pero no en individuos (16775 y 47 ± 32). La diversidad fue baja (componente: Simpson = 1; infracomunidad: Brillouin = 0.24 ± 0.11). La similitud en cada mes fue baja para componente (cualitativa, Jaccard: 0.25 ± 0.34; cuantitativa, % de similitud: 51 ± 49) e infracomunidad (cualitativa: 0.59 ± 0.24; cuantitativa: 46 ± 24). La similitud entre meses fue alta en componente (cualitativa: 0.63 ± 0.28; cuantitativa: 82 ± 15) e infracomunidad (cualitativa: 0.89 ± 0.10; cuantitativa: 77 ± 21). Hubo asociaciones significativas entre la abundancia de especies y el volumen de descarga de agua de los ríos entre meses, lo que sugiere que este parámetro influye fuertemente sobre la composición y estructura de estas comunidades. The component communities and infracommunities of Symphurus plagiusa were characterized for 37 sampling points from May to September 2003 along the Campeche coast. Possible statistical associations were also studied between the abundance of each helminth species and environmental parameters (e.g. salinity, oxygen concentration, river discharge water volumes) using redundancy analysis (RDA). We examined 531 hosts, whose component communities and infracommunities were poor in species number (maximum: 8 and 3 ± 1 respectively); but not in number of individuals (16775 and 47 ± 32). Diversity was low (component: Simpson = 1; infracommunity: Brillouin = 0.24 ± 0.11). Similarity within months was also low for both component communities (qualitative, Jaccard: 0.25 ± 0.34; quantitative, % of similarity: 51 ± 49) and infracommunities (qualitative: 0.59 ± 0.24; quantitative: 46 ± 24). Similarity between months was high for component communities (qualitative: 0.63 ± 0.28; quantitative: 82 ± 15) and infracommunities (qualitative: 0.89 + 0.10; quantitative: 77 ± 21). There were significant associations between the abundance of species and the river water discharges between months, which suggest high influence of this parameter on the structure and composition of these helminth communities.
Primer registro de Etropus ectenes Jordan, 1889, Bothus constellatus Jordan & Goss, 1889, Achirus klunzingeri (Steindachner, 1880) y Symphurus elongatus (Günther, 1868) (Pisces, Pleuronectiformes) en Chile, con comentarios sobre la distribución de los lenguados chilenos
Sielfeld,Walter; Vargas,Mauricio; Kong,Ismael;
Investigaciones marinas , 2003, DOI: 10.4067/S0717-71782003000100006
Abstract: . the first records of the pleuronectiformes achirus klunzingeri (soleidae), etropus ectenes and bothus constellatus (bothidae), and symphurus elongatus (cynoglossidae) in chilean waters are reported. the morphological characteristics of the studied specimens are compared with previous descriptions. their distribution in the southeastern pacific and that of the order in chilean waters are discussed
Primer registro de Etropus ectenes Jordan, 1889, Bothus constellatus Jordan & Goss, 1889, Achirus klunzingeri (Steindachner, 1880) y Symphurus elongatus (Günther, 1868) (Pisces, Pleuronectiformes) en Chile, con comentarios sobre la distribución de los lenguados chilenos First records of Etropus ectenes Jordan, 1889, Bothus constellatus Jordan & Goss, 1889, Achirus klunzingeri (Steindachner, 1880)  [cached]
Walter Sielfeld,Mauricio Vargas,Ismael Kong
Investigaciones Marinas , 2003,
Abstract: Se comunican los primeros registros de los Pleuronectiformes Achirus klunzingeri (Soleidae), Etropus ectenes y Bothus constellatus (Bothidae) y Symphurus elongatus (Cynoglossidae) en aguas de chilenas. Las características morfológicas de los especímenes estudiados se confrontan con descripciones previas. Se discute su distribución en el Pacífico sur oriental y aquella del orden en aguas chilenas . The first records of the Pleuronectiformes Achirus klunzingeri (Soleidae), Etropus ectenes and Bothus constellatus (Bothidae), and Symphurus elongatus (Cynoglossidae) in chilean waters are reported. The morphological characteristics of the studied specimens are compared with previous descriptions. Their distribution in the Southeastern Pacific and that of the order in Chilean waters are discussed
Histological Study on the Gonad of the Protandrous Anemonefish (Amphiprion ocellaris)
A.B. Abol-Munafi,N.H. Norazmi-Lokman,N.A. Asma,S. Sarmiza,M.Y. Abduh
Journal of Animal and Veterinary Advances , 2012, DOI: 10.3923/javaa.2011.3031.3036
Abstract: Standard histological protocol were performed on fifteen families of A. ocellaris collected at Pulau Bidong, Terengganu to describe and differentiate the gonad morphology between male, female and the non-breeders of protandrous Anemonefish (Amphiprion ocellaris). Based on the observations, non-breeder fish (3.5-5.8 cm TL) possess intermixed ovotestes with no clear boundaries between testicular and ovarian tissues. The ovotestes contained previtellogenic oocytes interspersed with fewer spermatocytes. Male fishes (5.3-6.9 cm TL) exhibited a different type of ovotestes. Male fish ovotestes were dominated by spermatogenic cells with fewer numbers of surrounding previtellogenic oocytes. In contrast, female fish gonadal tissue (6.0-9.2 cm TL) only contained ovarian tissues with no evidence of any testicular tissues. The ovarian was also larger and more mature than male and non breeders ovarian tissue with well organised ovigerous lamellae filled with oocytes visible at different developmental stages. The absence of the testicular tissues in the female gonad shows that the change of sex from male to female is an irreversible process.
EMBRYONIC DEVELOPMENT OF CLOWNFISH Amphiprion ocellaris UNDER LABORATORY CONDITIONS  [PDF]
H. J. LIEW, M. A. AMBAK, A. B. ABOL- MUNAFI,T. S. CHUAH
Journal of Sustainability Science and Management , 2006,
Abstract: This study illustrates the embryonic development of false clownfish, Amphiprion ocellaris under laboratory conditions. Broodstock were reared and spawned under captive conditions. The newly deposited egg was prolate spherical in shape with orange-pink and numerous oil droplets in the yolk. Cleavage was fast and the first division took place at 1:20 h after insemination. Blastulation was observed 4 hours later, followed by gastrulation after 12 h with a yolk volume at 0.63. Organogenisis process occurred after 22 h when the blastopores closed and notochord started to form. The embryonic stage was recorded at 24 h with the appearance of forebrain, midbrain, hindbrain, melanophores on yolk-sac and 22 somites. Other organs had developed well 31 hours later. Heart started beating and blood circulation occurred at 78 h. Red pigmentation (erytrophores) appeared at 96 h with a yolk volume at 0.21 mm3. Mouth developed well eye was noticeable at 120 h. The head, pectoral fin and tail moved frequently at 144 h and embryo reached the pre-hatching stage at 168 h. The embryo started to hatch at 180 h after incubation.
Temperature and the progeny sex-ratio in Sciara ocellaris (Diptera, Sciaridae)
Nigro, Rogério G.;Campos, Maria Cristina C.;Perondini, André Luiz P.;
Genetics and Molecular Biology , 2007, DOI: 10.1590/S1415-47572007000100026
Abstract: we found that the sex-ratio of an amphigenic strain of sciara ocellaris varied widely from progenies with few males to progenies containing a larger proportion of males, with single-sex progenies being rare. the sex-ratio distributions were dependent on the temperature at which the stocks of flies were raised, with the sex-ratio distributions being symmetrical (i.e. about 50% males) at 18 °c and 20 °c while at the higher temperatures of 24 °c and 28 °c the distributions were skewed toward a high proportion of females with the mean proportion of males decreasing to about 30-37% per progeny. temperature-shift experiments showed that high temperatures were effective only during the last stages of female pupal development plus a period after adult emergence, stages corresponding to oocyte maturation. when imagine females were exposed to temperatures as low as 12 °c the sex-ratio distributions of their progeny were skewed toward a high proportion of males per progeny. no differential fecundity was involved in these progeny sex-ratio modifications. egg-to-adult survival was lower at 18 °c and 28 °c but no correlations with skewing in the sex ratio distributions were observed, indicating that modifications in progeny sex-ratio did not involve the differential survival of a particular sex.
A??o predadora do tucunaré (Cichla ocellaris) sobre a tilapia do congo (Tilapia rendalli) (Osteichthyes, Cichlidae)
Nomura, Hitoshi;Menezes, J. F. S.;Souza, M. B. F. A.;
Revista Brasileira de Zoologia , 1982, DOI: 10.1590/S0101-81751982000100010
Abstract: an extensive cuivivation of the cichlids tilapia rendalli and its predator cichla ocellaris was undertaken at a lake in the ribeir?o preto (state of s?o paulo) campus of the university of s?o paulo. comparison of the results with former ones, obtained before the introduction of the predator, showed a considerable increase of tilapias, both in total length and total weight, showing the advantage of rearing them together.
Las comunidades de helmintos del lenguado (Symphurus plagiusa) en la costa de Campeche, México
Rodríguez-González, Abril;Vidal-Martínez, Víctor M.;
Revista mexicana de biodiversidad , 2008,
Abstract: the component communities and infracommunities of symphurus plagiusa were characterized for 37 sampling points from may to september 2003 along the campeche coast. possible statistical associations were also studied between the abundance of each helminth species and environmental parameters (e.g. salinity, oxygen concentration, river discharge water volumes) using redundancy analysis (rda). we examined 531 hosts, whose component communities and infracommunities were poor in species number (maximum: 8 and 3 ± 1 respectively); but not in number of individuals (16775 and 47 ± 32). diversity was low (component: simpson = 1; infracommunity: brillouin = 0.24 ± 0.11). similarity within months was also low for both component communities (qualitative, jaccard: 0.25 ± 0.34; quantitative, % of similarity: 51 ± 49) and infracommunities (qualitative: 0.59 ± 0.24; quantitative: 46 ± 24). similarity between months was high for component communities (qualitative: 0.63 ± 0.28; quantitative: 82 ± 15) and infracommunities (qualitative: 0.89 + 0.10; quantitative: 77 ± 21). there were significant associations between the abundance of species and the river water discharges between months, which suggest high influence of this parameter on the structure and composition of these helminth communities.
Familia Cynoglossidae - lengüetas  [cached]
Revista de Biología Tropical , 2005,
Abstract:
Estratégia trófica dos linguados Citharichthys spilopterus Günther e Symphurus tessellatus (Quoy & Gaimard) (Actinopterygii, Pleuronectiformes) na Baía de Sepetiba, Rio de Janeiro, Brasil
Guedes, Ana Paula Penha;Araújo, Francisco Gerson;Azevedo, Márcia Cristina Costa de;
Revista Brasileira de Zoologia , 2004, DOI: 10.1590/S0101-81752004000400020
Abstract: the aim of this study was to assess the spatial and ontogenetic changes in diet of the flatfishes citharichthys spilopterus günther, 1862 and symphurus tessellatus (quoy & gaimard, 1824) in the sepetiba bay. the studied area was divided in three zones (inner, central e outer), where bottom trawls were performed during the day, from october 1998 to september 1999. citharichthys spilopterus showed higher indices of relative importance (iri) for mysidacea (0.3359) and amphipoda (0.0805), while s. tessellatus showed the highest iri for amphipoda (0.7515) and polychaeta (0.2586). the high percentage (67.61%) of empty guts in s. tessellatus suggests nocturnal feeding activity. smaller sized individuals (tl < 115 mm) of c. spilopterus fed on mysidacea in the three bay zones, while the larger sized (tl > 115 mm) fed on polychaeta the inner zone, gobiidae in the central and decapoda in the outer. the smaller individuals (tl < 155 mm) of s. tessellatus fed mainly on amphipoda while the largest (tl > 155 mm) fed on polychaeta in the inner zone, and amphipoda and polychaeta in the outer zone. citharichthys spilopterus, shows comparatively larger mouth and eye, and feed on organisms in the water column nearby, with a more specialized feeding habit, compared with s. tessellatus, which feed on organism on the substrate. although the two species feed basically on crustacea, they present low overlaping in the diet (0.197), and this is probably the trophic strategy developed to allow the coexistence of these two closely related species in the bay.
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