L. Lanés - Academia.edu (original) (raw)
Papers by L. Lanés
Brazilian Journal of Biology
Annual fish live exclusively in temporary wetlands and are among the shortest-lived vertebrates i... more Annual fish live exclusively in temporary wetlands and are among the shortest-lived vertebrates in the world. These fish persist in these habitats due to drought-resistant eggs, that which, through diapauses are able to detect stimuli from the environment to start the development processes. They are also able to direct their embryonic development in different trajectories with different development times. Our objective in this paper was to describe the different stages of embryonic development of Austrolebias wolterstorffi, a critically endangered annual fish. A total of 27 stages of embryonic development were identified for the two observed developmental pathways (direct and diapause 2). Of these 27 developmental stages observed, 24 were identical between the two types of trajectories and three different. A total of 90% of the embryos that completed their development proceeded normally, without pauses. One embryo had a different development from the others, entering diapause 2, wit...
Check List, 2010
The present note extends the distribution of annual killifish Austrolebias periodicus, a endanger... more The present note extends the distribution of annual killifish Austrolebias periodicus, a endangered species,endemic of the Pampas region, in Ibicuí River basin, state of Rio Grande do Sul, southern Brazil. This information is neededto develop conservation strategies for this species and its habitat, which are at high risk due to the expansion of riceproduction and exotic forests in southern Brazil.
Check List, 2010
The present study records for the first time the small cichlidae fish Laetacara dorsigera (Heckel... more The present study records for the first time the small cichlidae fish Laetacara dorsigera (Heckel, 1840) atUruguay River basin and state of Rio Grande do Sul, southern Brazil, previously known from Amazon, Paraná and ParaguayRiver basins. Although the ichthyofauna of Uruguay River basin is relatively well known, this record suggests that thereare still unexplored environments, such as wetlands, where there may be species not yet reported, and found in otherhydrographic systems.
Ecology of Freshwater Fish, Mar 1, 2014
ABSTRACT Annual fishes, which inhabit temporary pools with extremely limited habitat complexity a... more ABSTRACT Annual fishes, which inhabit temporary pools with extremely limited habitat complexity and niche availability, display remarkable sexual dimorphism, rapid growth, and enormous investment into reproduction, all traits associated with high energy requirement. This study tests three hypotheses for two syntopic annual fishes (Austrolebias minuano and Cynopoecilus fulgens) found in six wetlands of southern Brazil: (i) considerable morphological differences result in low dietary overlap, (ii) sexual dimorphism in both species leads to intraspecific diet segregation, and (iii) dietary richness increases during ontogenetic development, and is narrower in C. fulgens than A. minuano due to morphological limitations imposed by reduced size. The diet of 82 A. minuano and 211 C. fulgens individuals was analyzed over two annual cycles. The morphology was characterized by 26 measurements covering the entire body of both species. There was no evidence of morphological specialization related to food competition and the diet of A. minuano and C. fulgens showed high overlap. High food availability, high predator abundance, and high connectivity of adjacent wetlands are likely the main mechanisms allowing coexistence of both species. Within species, sexual dimorphism did not result in a decrease in dietary overlap, which reinforces the idea that morphological differences between the sexes did not evolve as a mechanism to decrease food competition. Large A. minuano did not have a more diverse diet than the smaller C. fulgens; however, increase in body size allowed both species to ingest larger prey. Morphological variability in both species was mainly related to ontogenetic development and reproduction.
Neotropical Ichthyology
The family Rivulidae is the fourth most diverse clade of Neotropical fishes. Together with some g... more The family Rivulidae is the fourth most diverse clade of Neotropical fishes. Together with some genera of the related African family Nothobranchiidae, many rivulids exhibit a characteristic annual life cycle, with diapausing eggs and delayed embryonic development, which allows them to survive in the challenging seasonal ponds that they inhabit. Rivulidae also includes two species known as the only the self-fertilizing vertebrates and some species with internal fertilization. The first goal of this article is to review the systematics of the family considering phylogenetic relationships and synapomorphies of subfamilial clades, thus unifying information that is dispersed throughout the literature. From this revision, it is clear that phylogenetic relationships within Rivulidae are poorly resolved, especially in one of the large clades that compose it, the subfamily Rivulinae, where conflicting hypotheses of relationships of non-annual and annual genera are evident. The second goal of...
Journal of Applied Ichthyology, 2013
Journal of Applied Ichthyology, 2011
Journal of Applied Ichthyology, 2015
ABSTRACT Two hypotheses were tested: that the artificial sandbar opening decreases the richness, ... more ABSTRACT Two hypotheses were tested: that the artificial sandbar opening decreases the richness, diversity and abundance of fishes and alters the fish composition in floodplain ponds; that the salinity variations influence fish richness, diversity, abundance, as well as composition. Results suggest that artificial sandbar openings did not reduce the richness or diversity of freshwater fishes in southern Brazil floodplain ponds. Nevertheless, this process causes an increase in salinity, which determines significant differences in species composition between natural and managed areas. In this sense, the artificial sandbar opening must be considered with caution, since the area of study is one of the most important conservation units in wetland systems of southern Brazil.
Italian Journal of Zoology, 2013
Studies with annual fish diet have shown that the generalist habit is a dominant strategy within ... more Studies with annual fish diet have shown that the generalist habit is a dominant strategy within this group. Cynopoecilus fulgens (Cyprinodontiformes: Rivulidae) is a restricted range species, endemic to a small area in Southern Brazil, and aspects of its biology and ecology are poorly known. The main goal of the study was to determine the diet of C. fulgens throughout its life cycle and compare it with the prey availability in Southern Brazil wetlands. Specifically, we analyzed samples collected in different stages of ontogenetic development (immature and adult fishes) in various year seasons. A total of 52 food items were found in the diet of C. fulgens, and invertebrates comprised 96.4% of the counts observed. The richness of consumed and available prey changed along with the seasons. The seasonal variation of the consumed prey richness was mainly related to increase in fish size along the annual cycle. Microcrustaceans represented 75.6%, 80.9%, and 68.4% of the consumed prey in autumn, winter and spring, respectively. Prey composition varied with the seasons and it was not correlated to prey availability. Diet selectivity was different among male, female and immature fish. Our study reported the feeding habits of Cynopoecilus fulgens to improve knowledge of the biological and ecological traits of annual killifishes in Southern Brazil wetlands, where more than 90% of the original wetlands have been lost due to agricultural expansion.
Australian Mammalogy, 2013
Journal of Applied Ichthyology, 2015
ABSTRACT Two hypotheses were tested: that the artificial sandbar opening decreases the richness, ... more ABSTRACT Two hypotheses were tested: that the artificial sandbar opening decreases the richness, diversity and abundance of fishes and alters the fish composition in floodplain ponds; that the salinity variations influence fish richness, diversity, abundance, as well as composition. Results suggest that artificial sandbar openings did not reduce the richness or diversity of freshwater fishes in southern Brazil floodplain ponds. Nevertheless, this process causes an increase in salinity, which determines significant differences in species composition between natural and managed areas. In this sense, the artificial sandbar opening must be considered with caution, since the area of study is one of the most important conservation units in wetland systems of southern Brazil.
Brazilian Journal of Biology
Annual fish live exclusively in temporary wetlands and are among the shortest-lived vertebrates i... more Annual fish live exclusively in temporary wetlands and are among the shortest-lived vertebrates in the world. These fish persist in these habitats due to drought-resistant eggs, that which, through diapauses are able to detect stimuli from the environment to start the development processes. They are also able to direct their embryonic development in different trajectories with different development times. Our objective in this paper was to describe the different stages of embryonic development of Austrolebias wolterstorffi, a critically endangered annual fish. A total of 27 stages of embryonic development were identified for the two observed developmental pathways (direct and diapause 2). Of these 27 developmental stages observed, 24 were identical between the two types of trajectories and three different. A total of 90% of the embryos that completed their development proceeded normally, without pauses. One embryo had a different development from the others, entering diapause 2, wit...
Check List, 2010
The present note extends the distribution of annual killifish Austrolebias periodicus, a endanger... more The present note extends the distribution of annual killifish Austrolebias periodicus, a endangered species,endemic of the Pampas region, in Ibicuí River basin, state of Rio Grande do Sul, southern Brazil. This information is neededto develop conservation strategies for this species and its habitat, which are at high risk due to the expansion of riceproduction and exotic forests in southern Brazil.
Check List, 2010
The present study records for the first time the small cichlidae fish Laetacara dorsigera (Heckel... more The present study records for the first time the small cichlidae fish Laetacara dorsigera (Heckel, 1840) atUruguay River basin and state of Rio Grande do Sul, southern Brazil, previously known from Amazon, Paraná and ParaguayRiver basins. Although the ichthyofauna of Uruguay River basin is relatively well known, this record suggests that thereare still unexplored environments, such as wetlands, where there may be species not yet reported, and found in otherhydrographic systems.
Ecology of Freshwater Fish, Mar 1, 2014
ABSTRACT Annual fishes, which inhabit temporary pools with extremely limited habitat complexity a... more ABSTRACT Annual fishes, which inhabit temporary pools with extremely limited habitat complexity and niche availability, display remarkable sexual dimorphism, rapid growth, and enormous investment into reproduction, all traits associated with high energy requirement. This study tests three hypotheses for two syntopic annual fishes (Austrolebias minuano and Cynopoecilus fulgens) found in six wetlands of southern Brazil: (i) considerable morphological differences result in low dietary overlap, (ii) sexual dimorphism in both species leads to intraspecific diet segregation, and (iii) dietary richness increases during ontogenetic development, and is narrower in C. fulgens than A. minuano due to morphological limitations imposed by reduced size. The diet of 82 A. minuano and 211 C. fulgens individuals was analyzed over two annual cycles. The morphology was characterized by 26 measurements covering the entire body of both species. There was no evidence of morphological specialization related to food competition and the diet of A. minuano and C. fulgens showed high overlap. High food availability, high predator abundance, and high connectivity of adjacent wetlands are likely the main mechanisms allowing coexistence of both species. Within species, sexual dimorphism did not result in a decrease in dietary overlap, which reinforces the idea that morphological differences between the sexes did not evolve as a mechanism to decrease food competition. Large A. minuano did not have a more diverse diet than the smaller C. fulgens; however, increase in body size allowed both species to ingest larger prey. Morphological variability in both species was mainly related to ontogenetic development and reproduction.
Neotropical Ichthyology
The family Rivulidae is the fourth most diverse clade of Neotropical fishes. Together with some g... more The family Rivulidae is the fourth most diverse clade of Neotropical fishes. Together with some genera of the related African family Nothobranchiidae, many rivulids exhibit a characteristic annual life cycle, with diapausing eggs and delayed embryonic development, which allows them to survive in the challenging seasonal ponds that they inhabit. Rivulidae also includes two species known as the only the self-fertilizing vertebrates and some species with internal fertilization. The first goal of this article is to review the systematics of the family considering phylogenetic relationships and synapomorphies of subfamilial clades, thus unifying information that is dispersed throughout the literature. From this revision, it is clear that phylogenetic relationships within Rivulidae are poorly resolved, especially in one of the large clades that compose it, the subfamily Rivulinae, where conflicting hypotheses of relationships of non-annual and annual genera are evident. The second goal of...
Journal of Applied Ichthyology, 2013
Journal of Applied Ichthyology, 2011
Journal of Applied Ichthyology, 2015
ABSTRACT Two hypotheses were tested: that the artificial sandbar opening decreases the richness, ... more ABSTRACT Two hypotheses were tested: that the artificial sandbar opening decreases the richness, diversity and abundance of fishes and alters the fish composition in floodplain ponds; that the salinity variations influence fish richness, diversity, abundance, as well as composition. Results suggest that artificial sandbar openings did not reduce the richness or diversity of freshwater fishes in southern Brazil floodplain ponds. Nevertheless, this process causes an increase in salinity, which determines significant differences in species composition between natural and managed areas. In this sense, the artificial sandbar opening must be considered with caution, since the area of study is one of the most important conservation units in wetland systems of southern Brazil.
Italian Journal of Zoology, 2013
Studies with annual fish diet have shown that the generalist habit is a dominant strategy within ... more Studies with annual fish diet have shown that the generalist habit is a dominant strategy within this group. Cynopoecilus fulgens (Cyprinodontiformes: Rivulidae) is a restricted range species, endemic to a small area in Southern Brazil, and aspects of its biology and ecology are poorly known. The main goal of the study was to determine the diet of C. fulgens throughout its life cycle and compare it with the prey availability in Southern Brazil wetlands. Specifically, we analyzed samples collected in different stages of ontogenetic development (immature and adult fishes) in various year seasons. A total of 52 food items were found in the diet of C. fulgens, and invertebrates comprised 96.4% of the counts observed. The richness of consumed and available prey changed along with the seasons. The seasonal variation of the consumed prey richness was mainly related to increase in fish size along the annual cycle. Microcrustaceans represented 75.6%, 80.9%, and 68.4% of the consumed prey in autumn, winter and spring, respectively. Prey composition varied with the seasons and it was not correlated to prey availability. Diet selectivity was different among male, female and immature fish. Our study reported the feeding habits of Cynopoecilus fulgens to improve knowledge of the biological and ecological traits of annual killifishes in Southern Brazil wetlands, where more than 90% of the original wetlands have been lost due to agricultural expansion.
Australian Mammalogy, 2013
Journal of Applied Ichthyology, 2015
ABSTRACT Two hypotheses were tested: that the artificial sandbar opening decreases the richness, ... more ABSTRACT Two hypotheses were tested: that the artificial sandbar opening decreases the richness, diversity and abundance of fishes and alters the fish composition in floodplain ponds; that the salinity variations influence fish richness, diversity, abundance, as well as composition. Results suggest that artificial sandbar openings did not reduce the richness or diversity of freshwater fishes in southern Brazil floodplain ponds. Nevertheless, this process causes an increase in salinity, which determines significant differences in species composition between natural and managed areas. In this sense, the artificial sandbar opening must be considered with caution, since the area of study is one of the most important conservation units in wetland systems of southern Brazil.