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The genus Basilichthys (Teleostei: Atherinopsidae) revisited along its Chilean distribution range (21° to 40° S) using variation in morphologyand mtDNA
VéLIZ,DAVID; CATALáN,LAURA; PARDO,RODRIGO; ACU?A,PATRICIO; DíAZ,ANGIE; POULIN,ELIE; VILA,IRMA;
Revista chilena de historia natural , 2012, DOI: 10.4067/S0716-078X2012000100004
Abstract: there is still doubt as to the number of species of the freshwater chilean ichthyofauna, 64 % of which have conservation problems. one of the groups is that of the silversides of the genus basilichthys. three morphological species of this genus have been described in chile with disjoint distributions: basilichthys semotilus, b. microlepidotus and b. australis; the latter two overlap in distribution only in the aconcagua river and are not easily distinguishable by morphological and meristic characters. in order to evaluate the efficacy of identification of these species by molecular techniques, we analyzed the sequence of 9 % of the mitochondrial dna (control region and coi) of individuals from the loa river (21°41' s) to the valdivia river (39°50' s), adding meristic features for b. microlepidotus and b. australis in order to study population variation to clarify the taxonomy of the native species of the genus. the phylogenetic analysis showed that the individuals of basilichthys semotilus form an haplogroup separated from the other species of the genus; however, b. australis and b. microlepidotus form a monophyletic group that shares the most common haplotypes. an analysis of meristic information showed no statistically significant differences in the number of lateral line scales or number of rays in the fins between b. microlepidotus and b. australis. these results do not support the current classification for the latter two species; there appears to be one group in the extreme north of the country (basilichthys semotilus) and a second group in central chile which should be called b. microlepidotus. this information will be useful to review the conservation status of the chilean fauna.
Cross-amplification of microsatellites from the Atherinopsidae Odontesthes perugiae and Odontesthes argentinensis to Chilean silversides of the genus Odontesthes and Basilichthys
Mu?oz,Pablo; Quezada-Romegialli,Claudio; Vila,Irma; Véliz,David;
Gayana (Concepción) , 2011, DOI: 10.4067/S0717-65382011000200007
Abstract: we tested the amplification potential of 8 microsatellites initially described for odontesthes perugiae and o. argentinensis in 3 species of odontesthes and 4 species of basilichthys. most of the microsatellites amplified and showed polymorphism; thus they will be useful in genetic conservation plans for these species.
Temperature, energy acquisition and energy use in the Chilean silverside Basilichthys australis Eigenmann (Atherinopsidae)
FUENTES,LEOPOLDO; VILA,IRMA; CONTRERAS,MANUEL;
Revista chilena de historia natural , 2005, DOI: 10.4067/S0716-078X2005000200014
Abstract: we evaluated the influence of water temperature (tw) on the energy acquisition and use in the chilean silverside basilichthys australis (eigenmann 1927), an endemic species inhabiting freshwater ecosystems in chile. we tested the effect of tw (11.5, 14.0, 18.0, 22.0 and 26.0 °c) on food intake, digestibility, food transit time and metabolic rate. as expected, this study demonstrated that many physiological variables under study were significantly affected by tw, as well as the net energy balance of this species. nevertheless, the net energy balance was not strictly related to the range of tws evaluated. at tws lower than 14 °c the energy budget was depressed, because food intake was lower than at tws between 14 and 26 °c, where food intake was higher and independent of tw. consequently, at these temperatures the energy balance was positive and also independent of tw. physiologically, b. australis appears to be a tolerant species with respect to the wide range of water temperature in habitats at different depths. thus, its distributions may extend through the entire profile of lakes and rivers, even in systems characterised by spatial and temporal thermal variability
Aspectos cinemáticos del mecanismo de mordida premaxilar en los géneros Cauque, Basilichthys y Austromenidia (Teleostei, Atherinidae) Kinematic of the premaxillary bite ofthe genera Cauque, Basilichthys and Austromenidia (Teleostei, Atherinidae)  [cached]
EDUARDO DE LA HOZ U
Investigaciones Marinas , 1994,
Abstract: Se analiza el mecanismo de mordida premaxilar de distintas especies de los géneros Cauque, Austromenidia y Basilichthys, a través de modelos cinemáticos de cuatro barras, que permiten describir las características de los movimientos de las piezas bucales. En Cauque y Austromenidia las trayectorias angulares de premaxilar y mandíbula son semejantes y muestran un incremento en la velocidad del premaxilar a medida que se aproxima a la posición de cierre, mientras que en las especies de Basilichthys el premaxilar se mueve muy poco en relación al desplazamiento de la mandíbula y mantiene una velocidad angular constante durante toda la trayectoria. Se relacionan las características funcionales del mecanismo con las siguientes proporciones estructurales medidas en especímenes de varias especies: borde mandibular / distancia cuadrado-palatino, borde mandibular / longitud premaxilar, distancia cuadrado-palatino / protracción premaxilar máxima, y distancia cuadrado-palatino / borde mandibular The premaxillary bite mechanism of various species ofthe genera Cauque, Austromenidia and Basilichthys are analyzed through the four-bar linkage models; these models allow the description ofthe nature ofthe buccal structures movements. In Cauque and Austromenidia the angular trajectories of premaxilla and maxilla are similar, they show an increasing premaxilla velocity towards the cIosing position. In the Basilichthys species, the premaxilla movement is shorter than that of the mandible, and its velocity is maintained constant during all the trajectory. The functional characteristics of the mechanism are related to the following structural ratios: mandibular edge / quadrate-palatine distance, mandibular edge / premaxilla length, quadrate-palatine distance / maximal premaxillary protrusion, and quadrate-palatine distance / mandibular edge
Cross-amplification of microsatellites from the Atherinopsidae Odontesthes perugiae and Odontesthes argentinensis to Chilean silversides of the genus Odontesthes and Basilichthys Amplificación cruzada de microsatélites de los Atherinopsidae Odontesthes perugiae y Odontesthes argentinensis en pejerreyes chilenos del género Odontesthes y Basilichthys
Pablo Mu?oz,Claudio Quezada-Romegialli,Irma Vila,David Véliz
Gayana (Concepción) , 2011,
Abstract: We tested the amplification potential of 8 microsatellites initially described for Odontesthes perugiae and O. argentinensis in 3 species of Odontesthes and 4 species of Basilichthys. Most of the microsatellites amplified and showed polymorphism; thus they will be useful in genetic conservation plans for these species. Se prueba el potencial de amplificación de 8 microsatélites descritos inicialmente para Odontesthes perugiae y O. argentinensis en 3 especies de Odontesthes y 4 especies de Basilichthys. La mayoría de los partidores microsatélites amplificaron correctamente y presentan polimorfismo por lo que serán de utilidad en planes de conservación genética de estas especies.
Temperature, energy acquisition and energy use in the Chilean silverside Basilichthys australis Eigenmann (Atherinopsidae) Temperatura, adquisición de energía y uso de energía en el pejerrey chileno Basilichthys australis Eigenmann (Atherinopsidae)  [cached]
LEOPOLDO FUENTES,IRMA VILA,MANUEL CONTRERAS
Revista chilena de historia natural , 2005,
Abstract: We evaluated the influence of water temperature (Tw) on the energy acquisition and use in the chilean silverside Basilichthys australis (Eigenmann 1927), an endemic species inhabiting freshwater ecosystems in Chile. We tested the effect of Tw (11.5, 14.0, 18.0, 22.0 and 26.0 °C) on food intake, digestibility, food transit time and metabolic rate. As expected, this study demonstrated that many physiological variables under study were significantly affected by Tw, as well as the net energy balance of this species. Nevertheless, the net energy balance was not strictly related to the range of Tws evaluated. At Tws lower than 14 °C the energy budget was depressed, because food intake was lower than at Tws between 14 and 26 °C, where food intake was higher and independent of Tw. Consequently, at these temperatures the energy balance was positive and also independent of Tw. Physiologically, B. australis appears to be a tolerant species with respect to the wide range of water temperature in habitats at different depths. Thus, its distributions may extend through the entire profile of lakes and rivers, even in systems characterised by spatial and temporal thermal variability En este trabajo evaluamos la influencia de la temperatura del agua (Ta) en la adquisición de energía y su uso por parte del pejerrey chileno Basilichthys australis (Eigenmann 1927), una especie endémica que habita los ecosistemas dulceacuícolas de Chile. Investigamos el efecto de Ta (11,5, 14,0, 18,0, 22,0 y 26,0 °C) en la ingesta de alimento, digestibilidad, tiempo de transito del alimento y tasa metabólica. De acuerdo a lo esperado, este estudio demostró que varias de las variables fisiológicas bajo estudio fueron significativamente afectadas por Ta, así como el balance energético de esta especie. Sin embargo, el balance neto de energía no estuvo estrictamente relacionado al rango de Tas evaluadas. En Tas inferiores a 14 °C el presupuesto de energía fue deprimido, debido a que la ingesta de alimento fue inferior que en Tas entre 14 y 26 °C, donde la ingesta de alimento fue mayor e independiente de Ta. Consecuentemente, en estas temperaturas el balance de energía fue positivo y también independiente de Ta. Fisiológicamente, B. australis parece ser una especie tolerante en un amplio rango de temperaturas acuáticas en hábitats de diferentes profundidades. Así, su distribución puede extenderse a través del entero perfil vertical de lagos y ríos, aun en sistemas caracterizados por presentar variabilidad termal en las escalas espacial y temporal
Aspectos cinemáticos del mecanismo de mordida premaxilar en los géneros Cauque, Basilichthys y Austromenidia (Teleostei, Atherinidae)
DE LA HOZ U,EDUARDO;
Investigaciones marinas , 1994, DOI: 10.4067/S0717-71781994002200003
Abstract: the premaxillary bite mechanism of various species ofthe genera cauque, austromenidia and basilichthys are analyzed through the four-bar linkage models; these models allow the description ofthe nature ofthe buccal structures movements. in cauque and austromenidia the angular trajectories of premaxilla and maxilla are similar, they show an increasing premaxilla velocity towards the ciosing position. in the basilichthys species, the premaxilla movement is shorter than that of the mandible, and its velocity is maintained constant during all the trajectory. the functional characteristics of the mechanism are related to the following structural ratios: mandibular edge / quadrate-palatine distance, mandibular edge / premaxilla length, quadrate-palatine distance / maximal premaxillary protrusion, and quadrate-palatine distance / mandibular edge
Registro de Atherinella blackburni (Schultz) (Actinopterygii, Teleostei, Atherinopsidae) na praia de Ponta da Ilha, Ilha de Itaparica, Bahia, Brasil
Lopes, Paulo Roberto Duarte;Oliveira-Silva, Jailza Tavares de;
Revista Brasileira de Zoologia , 2001, DOI: 10.1590/S0101-81752001000100012
Abstract: atherinella blackburni (schultz, 1949) (atherinopsidae), is known in the atlantic ocean in costa rica, south of caribe and from venezuela to central brazil. the distribution and the intraespecific variation of characters of a. blackburni are poorly known. this study records a. blackburni in bahia littoral and presents more informations about its intraespecific variation.
Lordosis in topsmelt Atherinops affinis (Ayres, 1860) (Teleostei: Atherinopsidae)
De La Cruz-Agüero,José; Perezgómez-Alvarez,Liduvina;
Revista de biología marina y oceanografía , 2001, DOI: 10.4067/S0718-19572001000100010
Abstract: the first report of lordosis (vertebral curvature) in topsmelt atherinops affinis is described from one specimen collected at laguna ojo de liebre, baja california sur (méxico).
Atherinella blackburni (Schultz, 1949) at Itamambuca Beach, Ubatuba, SP: ecological characterization and distribution on the Brazilian coast (Teleostei: Atheriniformes: Atherinopsidae)
Mattox, GMT.;Gondolo, GF.;Cunningham, PTM.;
Brazilian Journal of Biology , 2008, DOI: 10.1590/S1519-69842008000200011
Abstract: atherinella blackburni is a silverside species whose occurrence on the brazilian coast was not properly registered until recently. so far, records of its distribution along the brazilian shore were limited to itaparica island, bahia state, and porto inhaúma, rio de janeiro state. in a recent survey of the ichthyofauna of itamambuca beach, ubatuba, s?o paulo state, 100 specimens of this species were collected, yielding a considerable source of information regarding its ecology and a new southern limit of its distribution. a detailed survey of an ichthyological collection revealed lots of this species from regions of the brazilian northeast, resulting in a northward expansion of the occurrence of a. blackburni in brazilian waters. besides the populations found on the brazilian coast, the species also occurs discontinuously in the atlantic coasts of costa rica, panama and venezuela. meristic and morphometric analysis showed overlapped values between brazilian populations and the ones closer to the caribbean. an ecological study of a. blackburni at itamambuca beach revealed that it is a predominantly diurnal species with preference for warm and salty waters, often occurring in sandy-bottom environments. it was more abundant in summer and winter, when individuals with smaller values of length and weight also occurred.
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