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Registros recuperados: 34
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A ictiofauna do Parque Estadual do Cantão, Estado do Tocantins, Brasil Biota Neotropica
Ferreira,Efrem; Zuanon,Jansen; Santos,Geraldo dos; Amadio,Sidinéia.
O Parque Estadual do Cantão é uma área protegida no rio Araguaia. Em um inventário realizado durante um ciclo hidrológico completo, foram capturadas 271 espécies de peixes, pertencentes a 183 gêneros, 41 famílias e 12 ordens. Characidae foi a família mais diversa com 89 espécies (32,6% do total), seguida por Loricariidae com 23 espécies (8,4%) e Cichlidae com 21 espécies (7,7%), dez famílias foram representadas por uma única espécie. Os resultados mostraram que o PE Cantão é uma área com alta diversidade de espécies de peixes, e que as assembleias ainda estão bem preservadas, de modo que a existência e manutenção deste Parque é de alto interesse para a preservação da fauna de peixes do rio Araguaia.
Tipo: Info:eu-repo/semantics/article Palavras-chave: Biodiversidade; Amazônia; Unidade de conservação; Pesca; CPUE.
Ano: 2011 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1676-06032011000200028
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A new species of Astyanax (Characiformes: Characidae) from the rapids of the lower rio Xingu, Brazil Neotropical Ichthyology
Lima,Flávio C.T.; Zuanon,Jansen.
Astyanax dnophos, new species, is described from the lower rio Xingu, Pará, Brazil. The new species is distinguished from its purported congeners by the presence of a broad longitudinal, midlateral dark stripe that extends from the snout to the caudal peduncle. Astyanax dnophos dwells on shadowed, rocky shelters on rapids, and it is apparently one of the few species of Characidae outside Serrasalminae reported to be rheophilic.
Tipo: Info:eu-repo/semantics/article Palavras-chave: Rheophily; Amazon basin; Taxonomy; Longitudinal stripe; Rocky shelter.
Ano: 2004 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252004000300002
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A new species of Boehlkea (Characiformes: Characidae: Stevardiinae) from the rio Japurá, Amazon basin, Brazil Neotropical Ichthyology
Soares,Isabel M.; Bertaco,Vinicius A.; Ito,Priscila Madoka M.; Zuanon,Jansen.
ABSTRACT A new species of Boehlkea is described from rio Japurá, Amazon basin. The new species differs from B. fredcochui by the presence of a vertically elongate humeral spot (vs. absence), complete lateral line (vs. incomplete), four rows of scales below lateral line (vs. three), and lower number of branched anal-fin rays (17-21 vs. 22-25), and from B. orcesi by the higher number of maxillary teeth (13-14 vs. 5-12), greater head length (27.9-29.9% vs. 24.3-27.5% of SL), and by the color pattern (basal half of dorsal-fin, distal portion of pelvic-fin, lower caudal-fin lobe and anal-fin with black chromatophores vs. absence of black chromatophores in the fins).
Tipo: Info:eu-repo/semantics/article Palavras-chave: Characidae “Clade A”; Color pattern; Hemibrycon; Lateral line length; Taxonomy.
Ano: 2017 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252017000300206
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A new species of Paralithoxus (Siluriformes: Loricariidae: Ancistrini) from the highlands of Serra da Mocidade, Roraima State, Brazilian Amazon Neotropical Ichthyology
Rapp-Py-Daniel,Lúcia; Oliveira,Andreza S.; Bastos,Douglas A.; Ito,Priscila Madoka M.; Zuanon,Jansen; Briglia-Ferreira,Sylvio Romério.
ABSTRACT A new species of Paralithoxus is described from the Ajarani River, a small tributary of the Branco River basin, Roraima State, Brazilian Amazon. The genus Paralithoxus comprises species described from the Essequibo drainage in Guyana, Approuague and Maroni in French Guiana, Suriname River in Surinam, and more recently, from Jari and Amapá rivers, in Brazil. Despite occurring in a rock-bottomed fast-flowing stream as the other species of Paralithoxus, this is the first species of the genus collected at 900 m altitude, in the Serra da Mocidade highlands, an isolated and poorly accessible small mountain chain at the southern border of the Guiana Shield. The new species is distinguished from its congeners by having truncate teeth, color pattern with...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Altitudinal fishes; Morphology; Osteology; Rio Branco basin; Taxonomy.
Ano: 2019 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252019000500209
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A remarkable sand-dwelling fish assemblage from central Amazonia, with comments on the evolution of psammophily in South American freshwater fishes Neotropical Ichthyology
Zuanon,Jansen; Bockmann,Flávio A.; Sazima,Ivan.
We studied a specialised assemblage of sand-dwelling fish species from a streamlet in central Amazonia. The five sanddwelling species comprised 15.2 % of the total number in the streamlet (33 species). Two of the sand-dwellers are daytime foragers, Characidium cf. pteroides (Crenuchidae) and Stauroglanis gouldingi (Trichomycteridae), whereas three ones are night-time foragers, Gymnorhamphichthys rondoni (Rhamphichthyidae), "Imparfinis" pristos and Mastiglanis asopos (Heptapteridae). With the exception of C. cf. pteroides, the remainder species bury in the sand during their resting period. All five species bear a cryptic, sand-colour pattern, and some are translucent, traits which we regard as advantageous both for evasion from predators and for approaching...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Forest streams; Fish diversity; Phylogeny; Feeding behaviour; Drift-trap net.
Ano: 2006 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252006000100012
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Catfishes as prey items of Potamotrygonid stingrays in the Solimões and Negro rivers, Brazilian Amazon Biota Neotropica
Shibuya,Akemi; Zuanon,Jansen.
In spite of the fact that catfish have rarely been reported as food items in the diets of freshwater stingrays, they are commonly observed in the stomach contents of species inhabiting the Solimões and Negro rivers in the Brazilian Amazon. The stomach contents of six rays from the Solimões River and 64 from the Negro River were analyzed, and catfishes (distributed among the families Callichthyidae, Cetopsidae, Doradidae and Loricariidae) were found in the stomach contents of four and 10 of these rays, respectively, comprising a frequency of occurrence of 20%. These data indicate a relevant participation of catfishes in the diets of potamotrygonid rays in the Amazon, and may reflect the regional diversity and abundance of Siluriformes in the region.
Tipo: Info:eu-repo/semantics/article Palavras-chave: Diet; Feeding; Freshwater stingrays; Myliobatiformes; Siluriformes.
Ano: 2013 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1676-06032013000100041
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Centromochlus meridionalis, a new catfish species from the southern Amazonian limits, Mato Grosso State, Brazil (Siluriformes: Auchenipteridae) Neotropical Ichthyology
Sarmento-Soares,Luisa Maria; Cabeceira,Fernando G.; Carvalho,Lucélia Nobre; Zuanon,Jansen; Akama,Alberto.
Centromochlus actually comprises eleven species, being the most problematic genus among the Centromochlinae, including morphologically heterogeneous taxa. The Centromochlus species have a wide distributional area on northern South America. Centromochlus meridionalis, new species, is described from headwaters of rio Teles Pires, contributor of rio Tapajós, Mato Grosso State, Brazil, and represents one of the southernmost records of a centromochlin catfish for Meridional Amazon rivers. Centromochlus meridionalis is promptly distinguished from its congeners by the small orbital diameter (relative to head length), and also by the combination of absence of first nuchal plate, anterior margin of dorsal-fin spine smooth, six branched rays in anal fin, seven pairs...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Amazon; Centromochlinae; Forest streams; Taxonomy; Teles Pires.
Ano: 2013 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252013000400797
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Color changing and behavioral context in the Amazonian Dwarf Cichlid Apistogramma hippolytae (Perciformes) Neotropical Ichthyology
Rodrigues,Raoni Rosa; Carvalho,Lucélia Nobre; Zuanon,Jansen; Del-Claro,Kleber.
Animal coloration has many functions, and fishes are noted among vertebrates for presenting a wide variety of color patterns. Although in marine fishes the relationship between body coloration and behavioral context is well documented, there's not much information about freshwater fishes. Here we describe color patterns displayed by the dwarf cichlid Apistogramma hippolytae and suggest that these patterns are dependent on different social and behavioral settings. Field observations were conducted underwater in a pond in Central Amazonia, Brazil. We recorded six body coloration patterns related to seven different kinds of behavioral activities: foraging, resting, reproductive and agonistic displays, aggression (attacking and fleeing) and parental care....
Tipo: Info:eu-repo/semantics/article Palavras-chave: Intraspecific communication; Interspecific communication; Color changes; Parental care; Cichlidae.
Ano: 2009 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252009000400013
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Comparação da eficiência de dois métodos de coleta de peixes em igarapés de terra firme da Amazônia Central Acta Amazonica
Ribeiro,Odirlene Marinho; Zuanon,Jansen.
Em estudos sobre distribuição espacial, alimentação e estrutura de comunidades de espécies de peixes de pequeno porte em igarapés, são aplicados alguns métodos de coleta específicos para esses ambientes. Este trabalho teve como objetivo principal comparar dois métodos de coleta, um ativo (puçá e peneira) e outro passivo (armadilhas). A coleta com puçá foi mais eficiente, tanto em número de espécies registradas, quanto em número de indivíduos capturados. Houve uma taxa de escape aparentemente elevada nas armadilhas, assim como a predação de parte dos peixes capturados por jejus (Erythrinus erythrinus) dentro das armadilhas, o que pode ter contribuído para a menor eficiência desse método. A baixa similaridade entre os pares de amostras coletadas com os dois...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Ictiofauna; Riqueza de espécies; Riachos; Armadilha; Puçá.
Ano: 2006 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0044-59672006000300017
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Description of a new species of Parancistrus (Siluriformes: Loricariidae) from the rio Xingu, Brazil Neotropical Ichthyology
Rapp Py-Daniel,Lúcia H.; Zuanon,Jansen.
Parancistrus nudiventris, new species, is described and compared with the congener P. aurantiacus. The new species has only been recorded from rio Xingu and can be distinguished from P. aurantiacus by having a naked abdomen (plated in P. aurantiacus), the presence of bluish dots in living specimens or spotted in preserved specimens (uniformly dark or clear brown or mottled, never spotted in P. aurantiacus), larger interbranchial distance (39-56% in HL vs. 24.9-39.5% in P. aurantiacus), narrower interorbital distance (26.8-38% in HL vs. 38.5-43.1% in P. aurantiacus). Parancistrus nudiventris also has buccal teeth more conspicuous than in P. aurantiacus. Main skeletal differences include the presence of a strong condyle on the lateral ethmoid for...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Parancistrus nudiventris; Freshwater fishes; Amazon basin; Natural History; Neotropical catfishes.
Ano: 2005 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252005000400014
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Diet and trophic structure of the fish assemblage in the mid-course of the Teles Pires River, Tapajós River basin, Brazil Neotropical Ichthyology
Dary,Eurizângela P.; Ferreira,Efrem; Zuanon,Jansen; Röpke,Cristhiana P..
ABSTRACT This study was carried out in a section of the middle course of the Teles Pires River, a clear water river that drains ancient and highly eroded geological formations, and where five hydropower plants are planned or in construction. In this study we tested the hypothesis that local fish fauna is mainly sustained by autochthonous food resources, with modest changes in the trophic structure of fish assemblages along the hydrometric cycle. Sampling was performed every three months between July 2008 and May 2009 at seven sites distributed along a 50-km section of the river. Piscivores was the most representative group in terms of biomass, abundance and species richness, followed by herbivores, insectivores and omnivores. The trophic structure did not...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Amazon; Environmental impact; Food resources; Temporal dynamics; Trophic ecology.
Ano: 2017 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252017000400201
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Diet of two syntopic species of Crenuchidae (Ostariophysi: Characiformes) in an Amazonian rocky stream Biota Neotropica
Fernandes,Suzanne; Leitão,Rafael Pereira; Dary,Eurizângela Pereira; Guerreiro,Ana Isabel Camacho; Zuanon,Jansen; Bührnheim,Cristina Motta.
Abstract This study assessed the diet of two poorly known syntopic fish species of the family Crenuchidae, Characidium aff. declivirostre and Leptocharacidium omospilus, in a Presidente Figueiredo´ rocky stream, Amazonas, Brazil. The stomach contents were analyzed and their Frequency of Occurrence (FO %) and Relative Volume (Vol %) were combined in a Feeding Index (IAi). We examined 20 individuals of C. aff. declivirostre and 23 of L. omospilus. The Morisita-Horn Index was used to estimate the overlap between the diets of these species. Immature insects were the most valuable items consumed by both fish species. The diet of C. aff. declivirostre was mainly composed of larvae and pupae of Chironomidae, while L. omospilus predominantly consumed larvae of...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Stream fish; Co-existence; Feeding overlap.
Ano: 2017 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1676-06032017000100206
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Evidence of multiple paternity and cooperative parental care in the so called monogamous silver arowana Osteoglossum bicirrhosum (Osteoglossiformes: Osteoglossidae) Neotropical Ichthyology
Verba,Júlia Tovar; Rabello Neto,José Gurgel; Zuanon,Jansen; Farias,Izeni.
Monogamy is rare in fishes and is usually associated with elaborate parental care. When parental care is present in fishes, it is usually the male that is responsible, and it is believed that there is a relationship between the high energetic investment and the certainty of paternity (except in the case of sneaker males). Osteoglossum bicirrhosum is considered a monogamous fish, and has particular behavioral traits that permit the study of mating systems and parental care, such as male mouthbrooding. We investigated the genetic relationships of males with the broods found in their oral cavities in Osteoglossum samples collected in a natural environment in the lower Purus river basin, Amazonas, Brazil. Fourteen broods were analyzed for parentage (268 young...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Cooperative parental care; Microsatellite; Monogamy; Mouthbrooding.
Ano: 2014 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252014000100145
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Fallen leaves on the water-bed: diurnal camouflage of three night active fish species in an Amazonian streamlet Neotropical Ichthyology
Sazima,Ivan; Carvalho,Lucélia Nobre; Mendonça,Fernando Pereira; Zuanon,Jansen.
Resemblance to dead leaves is a well known type of camouflage recorded for several small vertebrates that dwell in the leaf and root litter on the ground. We present here instances of such resemblance in three species of nocturnal fishes (Siluriformes and Gymnotiformes) that spend the daytime among submersed root-tangle with leaf litter in Amazonian streams. All three species are very difficult to spot visually, due both to their shape and colors which blend with the substrate, as well as to the heterogeneous nature of their cover. Two species were recorded to lie on their sides, which adds to their resemblance to dead leaves. When disturbed, one species may drift like a waterlogged leaf, whereas another moves upwards the root-tangle, exposing its fore...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Crypsis; Leaf resemblance; Defence against predators; Siluriformes; Gymnotiformes.
Ano: 2006 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252006000100013
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Feeding behavior of the Neotropical freshwater stingray Potamotrygon motoro (Elasmobranchii: Potamotrygonidae) Neotropical Ichthyology
Shibuya,Akemi; Zuanon,Jansen; Tanaka,Sho.
The feeding mechanisms of elasmobranchs and their functioning have been receiving growing scientific attention, although less emphasis has yet to be directed towards batoid species. The present study investigated the use of orobranchial musculature during prey capture and processing behavior in Potamotrygon motoro. Ten orobranchial muscle groups were removed to determine their relative biomasses. The kinematics of the musculature was described based on videos of prey capture and manipulation under captive conditions recorded at 250 and 500 field/s. Analyses of the orobranchial musculature indicated that adductor muscles responsible for closing the mouth had high biomasses, which is consistent with their functions related to apprehend and manipulate the...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Batoidea; Kinematics; Orobranchial musculature; Prey manipulation.
Ano: 2012 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252012000100018
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Feeding ecology of the leaf fish Monocirrhus polyacanthus (Perciformes: Polycentridae) in a terra firme stream in the Brazilian Amazon Neotropical Ichthyology
Catarino,Michel F; Zuanon,Jansen.
Monocirrhus polyacanthus (Polycentridae) is a remarkable leaf-mimicking fish that inhabits streams, lake and river margins along the Amazon basin. Despite its obvious predatory habits and being frequently present in the international aquarium trade, little is known about its diet under natural conditions. We examined 35 specimens of leaf fish (28.5-82.0 mm SL), of which 19 had food the stomach. Thirty-three preys were found in the stomach contents, 19 of which were measured (2.0-33.0 mm total length). Up to five preys were found in the stomach contents of a single leaf fish specimen. The diet of the leaf fish was constituted by fish (63.15% FO, n = 12) and invertebrates (36.3% FO, n = 4); fish and invertebrate preys occurred together in three stomachs...
Tipo: Info:eu-repo/semantics/report Palavras-chave: Diet; Feeding behavior; Piscivory; Camouflage.
Ano: 2010 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252010000100022
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Feeding habits of giant otters Pteronura brasiliensis (Carnivora: Mustelidae) in the Balbina hydroelectric reservoir, Central Brazilian Amazon Rev. Bras. Zool.
Cabral,Márcia M. M.; Zuanon,Jansen; de Mattos,Gália E.; Rosas,Fernando C. W..
This study aimed to identify the diet of giant otters, Pteronura brasiliensis (Zimmermann, 1780) in the Balbina reservoir (01º55'S, 59º29'W), to compare it with literature data on the diet of giant otters from non-dammed areas, and to verify the effects of the seasonal changes in water levels on the feeding habits of Balbina otters. A total of 254 feces samples were collected and identified according to the lowest possible taxonomic level. Teleostei fish were present in 100% of the samples; two samples also presented monkey fur (n = 1) and sloth fur (n = 1), suggesting that the diet of P. brasiliensis, in the reservoir, is almost exclusively based on fish. Ten fish families were identified in our samples, six of which were exclusive to the Balbina Lake...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Amazon basin; Aquatic mammal; Conservation; Dam; Diet.
Ano: 2010 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702010000100008
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Following food clouds: feeding association between a minute loricariid and a characidiin species in an Atlantic Forest stream, Southeastern Brazil Neotropical Ichthyology
Leitão,Rafael P.; Caramaschi,Érica P.; Zuanon,Jansen.
Following behavior is a widespread feeding tactic among marine fishes, but remains poorly documented for freshwater fishes. The present study describes such association between two freshwater species: the minute armored catfish Parotocinclus maculicauda and the South American darter Characidium sp. During underwater observations in an Atlantic Forest stream, we recorded Characidium sp. closely following P. maculicauda (<5cm), catching the particles dislodged by this catfish's grazing activity. The following behavior displayed by the darter is considered opportunistic and possibly favors the capture of preys associated to the periphyton. This study is one of the few records of nuclear-follower feeding association between freshwater fishes and the first...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Following behavior; Foraging habits; Freshwater; Hypoptopomatinae; Crenuchidae.
Ano: 2007 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252007000300011
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Free meals on long-distance cruisers: the vampire fish rides giant catfishes in the Amazon Biota Neotropica
Zuanon,Jansen; Sazima,Ivan.
The trichomycterid catfishes known as candirus are renowned for their blood feeding, but information on their habits under natural conditions is very fragmentary and generally restricted to hosts or habitats. We recorded an undescribed species of the vandelliine genus Paracanthopoma riding the giant jau catfish, Zungaro zungaro (Pimelodidae), in the upper Amazon. The candirus were found on the host's caudal and pectoral fins, as well as the base of the dorsal fin, with their snouts buried up to the eyes in the tough skin of the catfish host. All of them had small amounts of partly digested blood in the distal part of the gut. Along the host's dorsal fin base we found a few additional tiny holes, most of them healed. We suggest that Paracanthopoma feeds on...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Trichomycteridae; Paracanthopoma sp.; Candiru; Blood-feeding; Phoresis; Dispersal; Pimelodidade; Zungaro zungaro; Amazon.
Ano: 2005 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1676-06032005000100012
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Functional trophic composition of the ichthyofauna of forest streams in eastern Brazilian Amazon Neotropical Ichthyology
Brejão,Gabriel Lourenço; Gerhard,Pedro; Zuanon,Jansen.
This study aimed to describe the functional organization of the ichthyofauna of forest streams from northeastern Pará State, Brazil, based on behavioral observation of species' feeding tactics. Seven streams were sampled between June and November, 2010, during snorkeling sessions, totaling 91h 51min of visual censuses at day, dusk, and night periods. Seventy three species distributed in six orders, 26 families and 63 genera were observed, with dominance of Characiformes, followed by Siluriformes. From information gathered by ad libitum observations, each species was included in one of 18 functional trophic groups (FTGs), according to two main characteristics: (1) its most frequently observed feeding tactic; and (2) its spatial distribution in the stream...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Feeding tactics; Natural history; Snorkeling.
Ano: 2013 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252013000200361
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