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Las infracomunidades de parásitos de dos especies de Scartichthys (Pisces: Blenniidae) en localidades cercanas del norte de Chile Parasite infracommunities of two blennid species, Scartichthys (Pisces: Blenniidae), at nearby localities off northern Chile  [cached]
KAREN FLORES,MARIO GEORGE-NASCIMENTO
Revista chilena de historia natural , 2009,
Abstract: Se comparan las infracomunidades de parásitos de dos especies congenéricas y simpátridas de peces marinos: Scartichthys viridis (Valenciennes 1836) y Scartichthys gigas (Steindachner 1876) (Pisces: Blenniidae), en tres localidades del intermareal rocoso de Iquique (20°32' S, 70°11' O), norte de Chile, separadas por no más de 6 km, con muestras recolectadas entre agosto y septiembre de 2005. El objetivo fue evaluar la variabilidad de la riqueza, abundancia, diversidad, dominancia y composición en una escala espacial y temporal reducida. En total, se recolectaron 2.110 individuos parásitos en los 134 hospedadores examinados, los que pertenecían a 14 taxa. Se encontró una gran similitud en la composición y en las propiedades agregadas de las infracomunidades, tanto entre especies de hospedadores como entre sitios de estudio. Se interpreta que las condiciones ambientales, los factores ecológicos como el uso del habitat y de los recursos alimentarios, y los factores evolutivos como el alto grado de parentesco de estas especies de Scartichthys, son las principales influencias en la alta similitud parasitaria encontrada. The infracommunities of metazoan parasites in two congeneric and sympatric marine fish species, Scartichthys viridis (Valenciennes 1836) and Scartichthys gigas (Steindachner 1876), were studied and compared between three localities of the intertidal rocky shore off the coast of northern Chile, near Iquique (20°32' S, 70°11' W), which were separated by no more than 6 km. Samples were collected between August and September 2005. The goal of this study was to assess the variability in richness, abundance, diversity, dominance and parasite composition between close localities sampled within a short period. In all, 2,110 parasite individuals were collected from the 134 hosts examined, and 14 parasite taxa were identified. There was great similarity in the aggregated and compositional properties of the infracommunities, both between host species, as well as among study sites. We interpret these results as indicating that ecological factors such as habitat use and dietary composition, and evolutionary factors, such as the close relatedness between Scartichthys species are the main causes influencing the high similarity found in parasite communities of these fish species.
Las infracomunidades de parásitos de dos especies de Scartichthys (Pisces: Blenniidae) en localidades cercanas del norte de Chile
FLORES,KAREN; GEORGE-NASCIMENTO,MARIO;
Revista chilena de historia natural , 2009, DOI: 10.4067/S0716-078X2009000100004
Abstract: the infracommunities of metazoan parasites in two congeneric and sympatric marine fish species, scartichthys viridis (valenciennes 1836) and scartichthys gigas (steindachner 1876), were studied and compared between three localities of the intertidal rocky shore off the coast of northern chile, near iquique (20°32' s, 70°11' w), which were separated by no more than 6 km. samples were collected between august and september 2005. the goal of this study was to assess the variability in richness, abundance, diversity, dominance and parasite composition between close localities sampled within a short period. in all, 2,110 parasite individuals were collected from the 134 hosts examined, and 14 parasite taxa were identified. there was great similarity in the aggregated and compositional properties of the infracommunities, both between host species, as well as among study sites. we interpret these results as indicating that ecological factors such as habitat use and dietary composition, and evolutionary factors, such as the close relatedness between scartichthys species are the main causes influencing the high similarity found in parasite communities of these fish species.
Inter-population thermal variability and physiological response in the intertidal fish Scartichthys viridis (Blenniidae) Variabilidad térmica intrapoblacional y respuesta fisiológica en el pez intermareal Scartichthys viridis (Blenniidae)
JOSé M PULGAR,FRANCISCO BOZINOVIC,F. PATRICIO OJEDA
Revista chilena de historia natural , 2007,
Abstract: Determining habitat conditions that generate individual physiological variability represents key basic knowledge to understand the direction of animal's responses to habitat change. The coastal fish Scartichthys viridis inhabits low intertidal pools along the Chilean coast. Because seawater in the low intertidal is renewed during every tidal cycle, this zone is characterized by a low thermal variation and abundant food within and between localities. We evaluated whether seawater thermal conditions and food availability of low intertidal pools registered in three localities of Chilean coast are sufficient to generate physiological and energetic differences in individuals of S. viridis captured from three geographic separate populations spanning approximately 1,200 km. Southern fishes acclimatized to 25 °C showed higher metabolic rates than those from other localities and thermal treatments. On the other hand, southern fishes in natural conditions showed higher condition factor than northern fishes. This evidence is sufficient to indicate that slight latitudinal differences in tidepool seawater temperature associated to differential food availability induced an energetic constraint in this species. Moreover, southern population of S. viridis may suffer important effects on energetic allocation if seawater temperature increases slightly, with repercussions on its geographic distribution in southern Pacific Ocean Determinar las condiciones del ambiente que generan variabilidad fisiológica, representa un conocimiento básico para comprender el sentido de la respuesta de los animales a los cambios en su habitat. El pez costero Scartichthys viridis habita las pozas bajas del intermareal a lo largo de la costa chilena. Debido a que el agua de mar se renueva en cada ciclo de marea en las pozas bajas, esta zona está caracterizada por una baja variación térmica y abundante alimento entre localidades. Nosotros evaluamos si las condiciones térmicas y la disponibilidad de alimento descrita para pozas bajas registradas en tres localidades de la costa chilena son suficientes para generar diferencias fisiológicas y energéticas en individuos de S. viridis capturados desde tres poblaciones separadas geográficamente por aproximadamente 1.200 km. Los peces del sur aclimatados a 25 °C mostraron una tasa metabólica mayor que los peces de las otras localidades y tratamientos. Por otra parte, en el ambiente natural, los peces del sur mostraron un factor de condición mayor que los peces del norte. Esta evidencia es suficiente para indicar que suaves diferencias latitudinales en l
Parasite communities of Scartichthys viridis (Pisces: Blenniidae) from Central Chile: locality vs. host length
Mu?oz-Muga,Pilar; Mu?oz,Gabriela;
Revista de biología marina y oceanografía , 2010, DOI: 10.4067/S0718-19572010000100018
Abstract: se describen y comparan las comunidades de parásitos en el pez blénido scartichthys viridis de el tabo y las cruces, dos localidades cercanas de chile central. catorce especies parásitas fueron encontradas, cuatro de ellas fueron persistentes a través de las muestras. hubo una correlación positiva y significativa entre la riqueza, la abundancia infracomunitaria de parásitos y la longitud total del hospedador. scartichthys viridis de ambas localidades tuvo similar composición parasitaria, aunque las diferencias locales en los descriptores parasitarios poblacionales y comunitarios, mayores en peces de las cruces, podrían atribuirse a que el tama?o corporal del hospedador fue significativamente mayor en las cruces que en el tabo.
Inter-population thermal variability and physiological response in the intertidal fish Scartichthys viridis (Blenniidae)
PULGAR,JOSé M; BOZINOVIC,FRANCISCO; OJEDA,F. PATRICIO;
Revista chilena de historia natural , 2007, DOI: 10.4067/S0716-078X2007000400005
Abstract: determining habitat conditions that generate individual physiological variability represents key basic knowledge to understand the direction of animal's responses to habitat change. the coastal fish scartichthys viridis inhabits low intertidal pools along the chilean coast. because seawater in the low intertidal is renewed during every tidal cycle, this zone is characterized by a low thermal variation and abundant food within and between localities. we evaluated whether seawater thermal conditions and food availability of low intertidal pools registered in three localities of chilean coast are sufficient to generate physiological and energetic differences in individuals of s. viridis captured from three geographic separate populations spanning approximately 1,200 km. southern fishes acclimatized to 25 °c showed higher metabolic rates than those from other localities and thermal treatments. on the other hand, southern fishes in natural conditions showed higher condition factor than northern fishes. this evidence is sufficient to indicate that slight latitudinal differences in tidepool seawater temperature associated to differential food availability induced an energetic constraint in this species. moreover, southern population of s. viridis may suffer important effects on energetic allocation if seawater temperature increases slightly, with repercussions on its geographic distribution in southern pacific ocean
Diet and parasites of the insular fish Scartichthys variolatus (Blenniidae) from Robinson Crusoe Island, Chile: How different is this from two continental congeneric species?
Díaz,Pablo E; Mu?oz,Gabriela;
Revista de biología marina y oceanografía , 2010, DOI: 10.4067/S0718-19572010000200011
Abstract: this study analyzed the diet and parasites of an insular blenniid fish, scartichthys variolatus, and then compared that with data published for two congeneric species from the south american pacific coast, s. viridis and s. gigas. fifty-two specimens of fish were collected during 2008 and 2009 from the intertidal zone of the robinson crusoe island, about 700 km off the coast of central chile. the most frequent food items in all the fish analyzed were algae. just two specimens of s. variolatus (3.8%) were parasitized only by the nematode pseudodelphis chilensis. despite the fact that all scartichthys spp. are herbivorous, and the diet was composed of similar species, there were differences in frequencies of some of the algae, maily in chaetomorpha sp. and polysiphonia sp. the low parasite species richness of s. variolatus contrasts with that of the continental congeneric species, s. viridis with 13 parasite species, and s. gigas with 13 species. therefore, the diet of these fishes can not explain differences in their parasite composition, so it is possible that environmental conditions, and the distance between the location of robinson crusoe island and the south american coast, had limited dispersal and distribution of hosts and parasites over time.
The use of otoliths and larval abundance for studying the spatial ecology of the blenny Scartichthys viridis (Valenciennes, 1836) in coastal central Chile
Hernández-Miranda,Eduardo; Veas,Rodrigo; Espinoza,C. Valeria; Thorrold,Simon R; Ojeda,F. Patricio;
Revista de biología marina y oceanografía , 2009, DOI: 10.4067/S0718-19572009000300009
Abstract: several studies in marine ecology have focused on evaluating what determines the spatial and temporal structure of organisms within the intertidal and coastal zone. our results suggest that individuals of scartichthys viridis, separated by spatial scales greater that 200 km, would also be demographically separated, having independent reproductive activity and population dynamics. such spatial difference is suggested by analyzing trace elements found in the otoliths of recruited specimens, which were obtained simultaneously from los molles and isla negra, central chile. considering larval dispersion potential (92-106 days), based on daily micro increments of otoliths, both populations could be connected. however, this may not be the case, since the behavioral trend of these fish during larval stages seems to be near the areas where they hatched. although this study does not fully reveal the specific biophysical mechanisms involved, it proposes some alternatives that may address such questions. these results may assist in guiding further studies towards explicitly determining population segregation at minor spatial scales, as well as the specific biophysical mechanisms that determine transport, larval dispersion and population connectivity of fishes in intertidal environments.
Does Mugil liza Valenciennes 1836 (Teleostei: Mugiliformes) occur in Argentinean waters?
Cousseau,María B; González Castro,Mariano; Figueroa,Daniel E; Gosztonyi,Atila E;
Revista de biología marina y oceanografía , 2005, DOI: 10.4067/S0718-19572005000200006
Abstract: the present paper deals with the occurrence of two nominal species of mugil (mugil liza valenciennes 1836 and mugil platanus günther 1880) in argentinean waters. the investigation is necessary to clarify the distribution of these species before any regional study on the biology can be made. in argentinean bibliographies, two members of the familiy mugilidae are mentioned as living in argentinean waters, m. liza valenciennes 1836 and m. platanus günther 1880, while recent revisions on the southwestern atlantic members of this family recognised m. liza as living in the caribbean and northern brazil and m. platanus along the southern coast of brazil and north of argentina. samples from six coastal localities and from a freshwater lagoon between 36 and 42os latitude, comprising a total of 369 individuals were examined and compared with type specimens of both nominal species and a sample of 38 individuals of m. platanus from río grande do sul, brazil (32os). morphometric and meristic data were recorded: morphometrics was analyzed by normalization of the individuals of each locality followed by principal component analysis and meristics were compared with the values from types and fresh specimens corresponding to m. platanus and m. liza. the comparative analysis indicated that m. liza does not occur in argentinean waters, being m. platanus the only permanent present species.
Two new protist species, Trypanoplasma ojedae sp. n. (Mastigophora: Kinetoplastida) and Trichodina lascrucensis sp. n. (Ciliophora: Peritrichida) in a blenniid fish, Scartichthys viridis, from the coast of Chile
Khan,Rasul A; Díaz,Freddy; George-Nascimento,Mario;
Revista de biología marina y oceanografía , 2008, DOI: 10.4067/S0718-19572008000300017
Abstract: two new protistan species were observed in a blenniid fish, scartichthys viridis, inhabiting tide pools at las cruces, central chile. trypanoplasma ojedae sp. n. (mastigophora: kinetoplastida) in the blood is characterized by its small size (29.8 ± 5.0 x 5.1 +1.2 mm), short anterior flagellum (4.9 ± 0.6 mm), anterior located kinetoplast (2.4 ± 0.2) and a prominent undulating membrane. all of 18 fish were infected and 67% were parasitized on the gills by an unidentified piscicolid leech that harbored developing and infective biflagellated stages. trichodina lascrucensis sp. n. (ciliophora: peritrichida) parasitized the gill fillaments of all fish. the ciliate is characterized by its body size (70.8 ± 8.4 mm), adhesive disc (53 ± 5.4 mm), denticular ring (33 ± 3.1 mm), mean number of denticles (32.8 ± 3.0), mean number of denticular pins (9.5 ± 1.0) and ovoid micronucleus located near to one of the macronuclear arms. since none of the two parasites was similar to any species described from marine tide pool habitats as well as from the pacific ocean, both are considered new species with the characteristics described herein.
Infracomunidades de parásitos eumetazoos del bagre de mar Aphos porosus (Valenciennes, 1837) (Actinopterygii: Batrachoidiformes) en Chile central
Cortés,Yurima; Mu?oz,Gabriela;
Revista de biología marina y oceanografía , 2008, DOI: 10.4067/S0718-19572008000200004
Abstract: this study describes and quantifies the eumetazoan parasite community of the toadfish aphos porosus (valenciennes, 1837). to accomplish this purpose, 30 toadfish individuals were collected from intertidal rocky pools at el tabo, central chile between october 2006 and january 2007. the descriptors of the parasite infracommunity (abundance, richness, diversity and eveness) were calculated and correlated with the host body weight to determine if these variables have any relationship. the trophic level in which the toadfish is positioned in its community is also suggested, according to the life cycles of the parasites found in the fish. from the total sample, 93% fish were parasitized and 2,104 parasite individuals, belonging to nine taxa, were collected. the cestodes of tetraphyllidea and the nematode pseudoterranova sp. were the most prevalent and abundant parasites. at the infracommunity level, only the abundances (numeric and volumetric) of parasites increased significantly with host body weight which may be a consequence of a major consumption of infected prey and accumulation of parasites because several parasite species were larvae and encysted in the celomatic cavity and muscles of the fish. at the infrapopulation level only tetraphyllidea showed a significant correlation between abundances and host body size. the toadfish would be in an intermediate trophic level; it preys over crustaceans which are intermediate hosts for several parasite species found in this study. at the same time, toadfish can be preyed by elasmobranchs and marine mammals which usually are definitive hosts of most endoparasite species found.
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