987 resultados para Freshwater fishes -- Iberian Peninsula


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The ability of 2 freshwater fishes, eastern rainbow fish Melanotaenia splendida splendida and fly-specked hardyhead Craterocephalus stercusmuscarum stercusmuscarum. native to North Queensland to prey on immature Aedes aegypti was evaluated under laboratory conditions. The predation efficiency of the 2 species was compared to the exotic guppy, Poecilia reticulata, which is commonly used as a biological control agent of mosquito larvae. Of the 3 fish species tested, M. s. splendida was shown to be the most promising agent for the biological control of Ae. aegypti that breed in wells. Melanotaenia s. splendida consumed significantly greater numbers of immature Ae. aegypti than P. reticulata, irrespective of developmental stage or light conditions. Unlike C. s. stercusmuscarum, M, s. splendida could be handled, transported, and kept in captivity for extended periods with negligible mortality. However, M. s. splendida was also an efficient predator of Litoria caerulea tadpoles, a species of native frog found in wells during the dry season. This result may limit the usefulness of M. s. splendida as a biological control agent of well-breeding Ae. aegypti and suggests that predacious copepods, Mesocyclops spp., are more suitable. However, the use of M. s. splendida as a mosquito control agent in containers that are unlikely to support frog populations (e.g., aquaculture tanks and drinking troughs) should be given serious consideration.

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We present new Rayleigh-wave dispersion maps of the western Iberian Peninsula for periods between 8 and 30 s, obtained from correlations of seismic ambient noise, following the recent increase in seismic broadband network density in Portugal and Spain. Group velocities have been computed for each station pair using the empirical Green's functions generated by cross-correlating one-day-length seismic ambient-noise records. The resulting high-path density allows us to obtain lateral variations of the group velocities as a function of period in cells of 0.5 degrees x 0.5 degrees with an unprecedented resolution. As a result we were able to address some of the unknowns regarding the lithospheric structure beneath SW Iberia. The dispersion maps allow the imaging of the major structural units, namely the Iberian Massif, and the Lusitanian and Algarve Meso-Cenozoic basins. The Cadiz Gulf/Gibraltar Strait area corresponds to a strong low-velocity anomaly, which can be followed to the largest period inverted, although slightly shifted to the east at longer periods. Within the Iberian Massif, second-order perturbations in the group velocities are consistent with the transitions between tectonic units composing the massif. (C) 2013 Elsevier B.V. All rights reserved.

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A new upper Miocene locality at Asseiceira (Rio Maior), near the top of the "Calcários de Almoster e Santarém" unit (Almoster and Santarém limestones) is studied. Animal and plant fossils are described. Comparisons are drawn to other localities related to the same unit: Freiria and Azambujeira (middle and upper levels, both with large mammals). Small mammals from Asseiceira and Freiria point out to a rather old age amidst the upper Vallesian, MN 10 mammal-unit. This gives a fairly accurate datation for the "Calcários de Almoster e Santarém" and for the short time span of the corresponding sedimentation. Climate was warm and quite dry, with contrasting seasons and arid events. During upper Vallesian times, climate in Iberian Peninsula was varied but drier than in France, and specially so in the inner basins. However in Portugal and in Catalonia climate would he less different in comparison with that of the Rhône basin. Environmental evolution has been important: at Freiria and Azambujeira (middle level) there were mainly shallow lacustrine environments that received ressurgence waters from the nearby "Maciço calcário". Humid areas were closely surrounded by dense forests and these by broader and drier savanna or steppe areas. Still later, carbonate sedimentation ended. For some time there was still a river system with oxbows; humid areas probably were decreasing in favour of surrounding, rather dry environments. This study stressed the nced for revision of the geology of the region of Rio Maior and for a new geological mapping of that area. Environmental evolution has been important: at Freiria and Azambujeira (middle level) there were mainly shallow lacustrine environments that received ressurgence waters from the nearby "Maciço calcário".

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Fragmentary skeletal remains of Percoid fishes (Teleostei, Percoidei) are described from the Upper Paleocene? or Lowermost Eocene(MN7) from Silveirinha. It is suggested that they belong to some primitive Percoids which are already known in the Iberian peninsula. They bear witness of an ancient westwards extension of the geographical distribution of Percoid fishes that are common in the lower levels of the Eocene in the Douro Basin in Spain.

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Constituted of isolated fragments with a smooth decoration, the turtle material from Silveirinha is examined in order to define its sure belonging to Neochelys, by comparison with other smooth turtles which may be present during the Palaeogene of Europe (freshwater Testudinidae, Erymnochelyinae, Bothremydidae). The elements are compared with the already known Neochelys species of the Eocene European localities. Questions are made about the possible geographical migrations of turtles between South and North during the early Eocene of western Europe. The phyletic relationships cannot be established but the species, seeming new and one of the more primitive as a whole (after the preserved elements), is the older from the Iberian Peninsula.

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One hundred and fourteen specimens of eleven different species of freshwater fishes from the Guaiba estuary, were examined for digenetic flukes. Saccocoelioides godoyi n.sp. proposed herein, is closest to S. magniovatus and to S. szidati; S. magniovatus is much smaller with comparably larger eggs and S. szidati has larger hermaphroditic sac and considerably larger testis. Creptotrema creptotrema is referred to a new host; Acanthostomum gnerii, Crepidostomum platense, Eocreadium intermedium (immature form), Parspina argentinensis and Zonocotyle bicaecata are reported. This paper confirms the similatary between the parasites of freshwater fishes from Argentina and Brazil. Measurements and original figures of all species are given.

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Procamallanus petterae n. sp. from Plecostomus albopunctarus and Spirocamallanus pintoi n. sp. from Corydoras paleatus are described. procamallanus petterae n. sp. differs from all other species of the genus by having a buccal capsule without spiral bands, with five teeth-like structures on its base and four plate-like structures near the anterior margin; length ratio of oesophagus muscular/glandular 1:1.4; spicules short, 21µ m and 16µ m long and tails ending abruptly in a sharp point, in both sexes. Spirocamallanus pintoi n. sp. is characterized by having 6 to 8 spiral thickenings in the buccal capsule of male and 9 to 10 in female, occupying 2/3 of the length of the capsule; length of glandular oesophagus more than twice the muscular; spicules short, the right 94µ m and the left 82µ m long.

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The pathology induced by the nematode Camallanus cotti in the aquarium fishes Beta splendens (beta fish) and Poecilia reticulata (guppy) consisted of gross and microscopic lesions, the former characterized by abdominal swelling with reddish parasites protruding from the anus in both fish hosts and the latter, similar in the beta fishes and guppies, by hemorrhage, congestion, edema, a few glandular elements, and extensive erosion areas in the rectum mucosa, with a marked thickening of the wall and absence of inflammatory infiltrate. Lesions were associated with the presence of several worms attached to the wall or free in the rectal lumen. This is the second reference of the parasite in Brazil and the first report of pathological findings related to this nematode species that is also briefly redescribed and illustrated for the first time on the basis of Brazilian samples.

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Seguimos para este taxon, en lo nomenclatural, a TAMURA & LAUENER (1979:459), mientras no se tipifique de forma adecuada A. lycoctonum L., considerado nom. ambig. ya por TUTIN (1964:212), con pocas posibilidades de que no sea diverso de A. vulparia. A. pyrenaicum L. es también algo muy distinto del taxon que nos ocupa y, en caso de no ser aceptada la proposición de que se lo considere ñamen rejiciendum, hecha por TAMURA & LAUENER (Le.: 447), seria el nombre correcto para A. barbatum Pers. (=A. squarrosum DC.) de Siberia. Otro nombre que aún podría ser prioritario, A. altissimum Miller (WARNCKE, 1964:30; TAMURA & LAUENER, l.c), no puede usarse en tanto no se localice algún material de aquel en que se basó la descripción un tanto ambigua de Miller....

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Al consultar los pliegos de Artemisia L. contenidos en el Herbario BCF, con motivo de la revisión de dicho género en la Península Ibérica, que estamos realizando como tesis doctoral, hemos hallado dos de ellos (BCF n.° 7473 y n.° 7475) recolectados por don Salvador Rivas Goday, el 17 de septiembre de 1948, en Titulcia (MADRID) y determinados como Artemisia variabilis Ten.

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The antibacterial and antifungal activity of 82 marine macroalgae (18 Chlorophyceae, 25 Phaeophyceae and 39 Rhodophyceae) was studied to evaluate their potential for being used as natural preservatives in the cosmetic industry. The bioactivity was analysed from crude extracts of fresh and lyophilised samples against three Gram-positive bacteria, two Gram-negative bacteria and one yeast using the agar diffusion technique. The samples were collected seasonally from Mediterranean and Atlantic coasts of the Iberian Peninsula. Of the macroalgae analysed, 67% were active against at least one of the six test microorganisms. The highest percentage of active taxa was found in Phaeophyceae (84%), followed by Rhodophyceae (67%) and Chlorophyceae (44%). Nevertheless, red algae had both the highest values and the broadest spectrum of bioactivity. In particular, Bonnemaisonia asparagoides, Bonnemaisonia hamifera, Asparagopsis armata and Falkenbergia rufolanosa (Bonnemaisoniales) were the most active taxa. Bacillus cereus was the most sensitive test microorganism and Pseudomonas aeruginosa was the most resistant. The highest percentages of active taxa from Phaeophyceae and Rhodophyceae were found in autumn, whereas they were found in summer for Chlorophyceae.

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Se presenta el estudio carpológico de las especies Ibéricas y Baleáricas del género Anthémis L. A partir de la valoración crítica de los caracteres empleados y de la descripción morfológica, al microscopio óptico y electrónico de barrido, de las cipselas de los táxones que integran el grupo, se ha confeccionado una clave que permite la identificación de las especies.

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Compsopogon coeruleus es un alga filamentosa de amplia distribución en aguas tropicales y subtropicales (KRISHNAMURTHY,/. Lian. Soc. (Bot.) 5 8 : 2 0 7 - 2 2 2 , 1962). En el curso del estudio sobre las fuentes de la zona de Banyoles (Gerona) la hemos recolectado en la Font de la Carpa, UTM: 31 TDG 7 6 ...

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En el presente trabajo se proponen cuatro cambios nomenclatures: Verbascum erosun Cav. (= V. laciniatum (Poiret) O. Kuntze); V. masguindali (Pau) comb, nov.; V. pseudocreticurn nom. nov. y V. fontqueri nom. nov. Se adjuntan dos nuevas ilustraciones, una clave dicotómica de las ocho especies ibéricas y baleáricas con cuatro estambres (Celsia L.) y una relación de los ejemplares de herbario estudiados. Verbascum masguindali se indica por primera vez en la Península Ibérica.