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Jean-marie Cabelguen - One of the best experts on this subject based on the ideXlab platform.
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EPAXIAL AND LIMB MUSCLE ACTIVITY DURING SWIMMING AND TERRESTRIAL STEPPING IN THE ADULT NEWT, PLEURODELES WALTL
Journal of Neurophysiology, 1997Co-Authors: Isabelle Delvolvé, Jean-marie CabelguenAbstract:Delvolve, Isabelle, Tiaza Bem, and Jean-Marie Cabelguen. Epaxial and limb muscle activity during swimming and terrestrial stepping in the adult newt, Pleurodeles waltl. J. Neurophysiol. 78: 638–650, 1997. We have investigated the patterns of activation of epaxial musculature during both swimming and overground stepping in an adult newt ( Pleurodeles waltl ) with the use of electromyographic (EMG) recordings from different sites of the myomeric muscle dorsalis trunci along the body axis. The locomotor patterns of some limb muscles have also been investigated. During swimming, the epaxial Myomeres are rhythmically active, with a strict alternation between opposite Myomeres located at the same longitudinal site. The pattern of intersegmental coordination consists of three successively initiated waves of EMG activity passing posteriorly along the anterior trunk, the midtrunk, and the posterior trunk, respectively. Swimming is also characterized by a tonic activation of forelimb (dorsalis scapulae and extensor ulnae) and hindlimb (puboischiotibialis and puboischiofemoralis internus) muscles and a rhythmic activation of muscles (latissimus dorsi and caudofemoralis) acting both on limb and body axis. The latter matched the activation pattern of epaxial Myomeres at the similar vertebral level. During overground stepping, the midtrunk Myomeres express single synchronous bursts whereas the Myomeres of the anterior trunk and those of the posterior trunk display a double bursting pattern in the form of two waves of EMG activity propagating in opposite directions. During overground stepping, the limb muscles and muscles acting on both limb and body axis were found to be rhythmically active and usually displayed a double bursting pattern. The main conclusion of this investigation is that the patterns of intersegmental coordination during both swimming and overground stepping in the adult newt are related to the presence of limbs and that they can be considered as hybrid lampreylike patterns. Thus it is hypothesized that, in newt, a chain of coupled segmental oscillatory networks, similar to that which constitutes the central pattern generator (CPG) for swimming in the lamprey, can account for both trunk motor patterns if it is influenced by limb CPGs in a way depending on the locomotor mode. During swimming, the segmental networks located close to the girdles receive extra tonic excitation coming from the limb CPGs, whereas during stepping, the axial CPGs are entrained to some extent by the limb oscillators.
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EPAXIAL AND LIMB MUSCLE ACTIVITY DURING SWIMMING AND TERRESTRIAL STEPPING IN THE ADULT NEWT, PLEURODELES WALTL
Journal of neurophysiology, 1997Co-Authors: Isabelle Delvolvé, Tiaza Bem, Jean-marie CabelguenAbstract:We have investigated the patterns of activation of epaxial musculature during both swimming and overground stepping in an adult newt (Pleurodeles waltl) with the use of electromyographic (EMG) recordings from different sites of the myomeric muscle dorsalis trunci along the body axis. The locomotor patterns of some limb muscles have also been investigated. During swimming, the epaxial Myomeres are rhythmically active, with a strict alternation between opposite Myomeres located at the same longitudinal site. The pattern of intersegmental coordination consists of three successively initiated waves of EMG activity passing posteriorly along the anterior trunk, the midtrunk, and the posterior trunk, respectively. Swimming is also characterized by a tonic activation of forelimb (dorsalis scapulae and extensor ulnae) and hindlimb (puboischiotibialis and puboischiofemoralis internus) muscles and a rhythmic activation of muscles (latissimus dorsi and caudofemoralis) acting both on limb and body axis. The latter matched the activation pattern of epaxial Myomeres at the similar vertebral level. During overground stepping, the midtrunk Myomeres express single synchronous bursts whereas the Myomeres of the anterior trunk and those of the posterior trunk display a double bursting pattern in the form of two waves of EMG activity propagating in opposite directions. During overground stepping, the limb muscles and muscles acting on both limb and body axis were found to be rhythmically active and usually displayed a double bursting pattern. The main conclusion of this investigation is that the patterns of intersegmental coordination during both swimming and overground stepping in the adult newt are related to the presence of limbs and that they can be considered as hybrid lampreylike patterns. Thus it is hypothesized that, in newt, a chain of coupled segmental oscillatory networks, similar to that which constitutes the central pattern generator (CPG) for swimming in the lamprey, can account for both trunk motor patterns if it is influenced by limb CPGs in a way depending on the locomotor mode. During swimming, the segmental networks located close to the girdles receive extra tonic excitation coming from the limb CPGs, whereas during stepping, the axial CPGs are entrained to some extent by the limb oscillators.
Isabelle Delvolvé - One of the best experts on this subject based on the ideXlab platform.
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EPAXIAL AND LIMB MUSCLE ACTIVITY DURING SWIMMING AND TERRESTRIAL STEPPING IN THE ADULT NEWT, PLEURODELES WALTL
Journal of Neurophysiology, 1997Co-Authors: Isabelle Delvolvé, Jean-marie CabelguenAbstract:Delvolve, Isabelle, Tiaza Bem, and Jean-Marie Cabelguen. Epaxial and limb muscle activity during swimming and terrestrial stepping in the adult newt, Pleurodeles waltl. J. Neurophysiol. 78: 638–650, 1997. We have investigated the patterns of activation of epaxial musculature during both swimming and overground stepping in an adult newt ( Pleurodeles waltl ) with the use of electromyographic (EMG) recordings from different sites of the myomeric muscle dorsalis trunci along the body axis. The locomotor patterns of some limb muscles have also been investigated. During swimming, the epaxial Myomeres are rhythmically active, with a strict alternation between opposite Myomeres located at the same longitudinal site. The pattern of intersegmental coordination consists of three successively initiated waves of EMG activity passing posteriorly along the anterior trunk, the midtrunk, and the posterior trunk, respectively. Swimming is also characterized by a tonic activation of forelimb (dorsalis scapulae and extensor ulnae) and hindlimb (puboischiotibialis and puboischiofemoralis internus) muscles and a rhythmic activation of muscles (latissimus dorsi and caudofemoralis) acting both on limb and body axis. The latter matched the activation pattern of epaxial Myomeres at the similar vertebral level. During overground stepping, the midtrunk Myomeres express single synchronous bursts whereas the Myomeres of the anterior trunk and those of the posterior trunk display a double bursting pattern in the form of two waves of EMG activity propagating in opposite directions. During overground stepping, the limb muscles and muscles acting on both limb and body axis were found to be rhythmically active and usually displayed a double bursting pattern. The main conclusion of this investigation is that the patterns of intersegmental coordination during both swimming and overground stepping in the adult newt are related to the presence of limbs and that they can be considered as hybrid lampreylike patterns. Thus it is hypothesized that, in newt, a chain of coupled segmental oscillatory networks, similar to that which constitutes the central pattern generator (CPG) for swimming in the lamprey, can account for both trunk motor patterns if it is influenced by limb CPGs in a way depending on the locomotor mode. During swimming, the segmental networks located close to the girdles receive extra tonic excitation coming from the limb CPGs, whereas during stepping, the axial CPGs are entrained to some extent by the limb oscillators.
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EPAXIAL AND LIMB MUSCLE ACTIVITY DURING SWIMMING AND TERRESTRIAL STEPPING IN THE ADULT NEWT, PLEURODELES WALTL
Journal of neurophysiology, 1997Co-Authors: Isabelle Delvolvé, Tiaza Bem, Jean-marie CabelguenAbstract:We have investigated the patterns of activation of epaxial musculature during both swimming and overground stepping in an adult newt (Pleurodeles waltl) with the use of electromyographic (EMG) recordings from different sites of the myomeric muscle dorsalis trunci along the body axis. The locomotor patterns of some limb muscles have also been investigated. During swimming, the epaxial Myomeres are rhythmically active, with a strict alternation between opposite Myomeres located at the same longitudinal site. The pattern of intersegmental coordination consists of three successively initiated waves of EMG activity passing posteriorly along the anterior trunk, the midtrunk, and the posterior trunk, respectively. Swimming is also characterized by a tonic activation of forelimb (dorsalis scapulae and extensor ulnae) and hindlimb (puboischiotibialis and puboischiofemoralis internus) muscles and a rhythmic activation of muscles (latissimus dorsi and caudofemoralis) acting both on limb and body axis. The latter matched the activation pattern of epaxial Myomeres at the similar vertebral level. During overground stepping, the midtrunk Myomeres express single synchronous bursts whereas the Myomeres of the anterior trunk and those of the posterior trunk display a double bursting pattern in the form of two waves of EMG activity propagating in opposite directions. During overground stepping, the limb muscles and muscles acting on both limb and body axis were found to be rhythmically active and usually displayed a double bursting pattern. The main conclusion of this investigation is that the patterns of intersegmental coordination during both swimming and overground stepping in the adult newt are related to the presence of limbs and that they can be considered as hybrid lampreylike patterns. Thus it is hypothesized that, in newt, a chain of coupled segmental oscillatory networks, similar to that which constitutes the central pattern generator (CPG) for swimming in the lamprey, can account for both trunk motor patterns if it is influenced by limb CPGs in a way depending on the locomotor mode. During swimming, the segmental networks located close to the girdles receive extra tonic excitation coming from the limb CPGs, whereas during stepping, the axial CPGs are entrained to some extent by the limb oscillators.
William Severi - One of the best experts on this subject based on the ideXlab platform.
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larvae and juveniles (Clupeiformes: Pristigasteridae)
2011Co-Authors: William Severi, Nelsy Fenerich VeraniAbstract:Pristigasterids are predominantly coastal marine sardines of tropical and subtropical seas, with some species being found in fresh water. Two species of the genus Pellona, P. castelnaeana Valenciennes, 1847 and P. flavipinnis (Valenciennes, 1837), inhabit fresh waters of the neotropical region, with the latter occurring in the Pantanal of Mato Grosso, in the Paraguay River basin of central Brazil. The development of P. flavipinnis larvae and early juveniles was characterized from an ontogenic series of 27 specimens (6.3–35 mm SL), based on morphological and meristic characters. The larval and juvenile development of this freshwater sardine are typical of most clupeiforms. Exact hatching size is unknown, but it is less than 6 mm standard length (SL) and the yolk is absorbed under 10 mm. Transformation to the flexion stage occurs at about 11 mm, to the postflexion stage between 16 and 19 mm, and to the juvenile stage after 26 mm. The ventral scutes begin to form between 25 and 31 mm, with the full complement of scutes (32 to 37) formed between 32 and 35 mm. Total Myomere count averages 42. As the dorsal fin and origin of the anal fin and vent migrate anteriorly, the preanal Myomere count ranges from 29 in the flexion larvae to 24 in early juveniles up to 35 mm. Corresponding preanal lengths range from 85 to 61%, respectively
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Morphological development of Pellona flavipinnis post-yolk-sac larvae and juveniles (Clupeiformes: Pristigasteridae)
Zootaxa, 2006Co-Authors: William Severi, Nelsy Fenerich VeraniAbstract:Pristigasterids are predominantly coastal marine sardines of tropical and subtropical seas, with some species being found in fresh water. Two species of the genus Pellona, P. castelnaeana Valenciennes, 1847 and P. flavipinnis (Valenciennes, 1837), inhabit fresh waters of the neotropical region, with the latter occurring in the Pantanal of Mato Grosso, in the Paraguay River basin of central Brazil. The development of P. flavipinnis larvae and early juveniles was characterized from an ontogenic series of 27 specimens (6.3–35 mm SL), based on morphological and meristic characters. The larval and juvenile development of this freshwater sardine are typical of most clupeiforms. Exact hatching size is unknown, but it is less than 6 mm standard length (SL) and the yolk is absorbed under 10 mm. Transformation to the flexion stage occurs at about 11 mm, to the postflexion stage between 16 and 19 mm, and to the juvenile stage after 26 mm. The ventral scutes begin to form between 25 and 31 mm, with the full complement of scutes (32 to 37) formed between 32 and 35 mm. Total Myomere count averages 42. As the dorsal fin and origin of the anal fin and vent migrate anteriorly, the preanal Myomere count ranges from 29 in the flexion larvae to 24 in early juveniles up to 35 mm. Corresponding preanal lengths range from 85 to 61%, respectively.
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Desenvolvimento inicial de larvas de Rhaphiodon vulpinus Agassiz (Characiformes, Cynodontidae)
Revista Brasileira de Zoologia, 2002Co-Authors: Wilson Treger Zydowicz De Sousa, William SeveriAbstract:The cynodontid fish Rhaphiodon vulpinus Agassiz, 1829, known as "peixe-cachorro", is the only species of the family oceurring in the Pantanal of Mato Grosso. The initial development of its larvae was characterized, based on material collected with a 500 µm mesh size plankton-net, in several biotopes of the Pantanal of Barao de Melgaco, State of Mato Grosso, Central Brazil. The analysis was carried out with 72 larvae with standard length (SL) between 4.7 and 13.8 mm. The morphometric measurements varied positively with standard length, and body proportions ranged 8.1-17.8% for head length (HL), 6.2-10.1% for body height, and 63.673.5%, 16.8-21.6%, and 61.8-78.2% SL, respectively for pre-dorsal, pre-pectoral and pre-anal distances. The eye diameter varied positively with HL and its proportion varied between 9.1 -22.5% HL. The body relations did not show great variation along the larval development. The morphologicai characterization of larvae from 4.7 to 5.8 mm SL, in the pre-flexion phase, showed lhe presence of anembryonic finfold covering the unraycd fins, exposed branchial arches, absence of exogenous digestive content, unpigmented eyes and round shaped head. Larvae with SL between 8.1 and 13.8 mm SL were in the flexion phase, presenting a pointed head, mouth filled with externai and internai rows of numerous teeth, presence of exogenous food, pigmented eyes, branchial filaments still exposed, evident swimming-bladder, and formation of the first caudal, dorsal and anal fins' rays. Only individuais in the pre-flexion and flexion phases were analyzed, and no completely developed fin was evidenced. A maximum number of 69 Myomeres was counted and no evident pigmentation over the body observed. Comparing R. vulpinus larvae to those of other Characiformes, it was observed that this species and Apareiodon affinis Steindachner, 1879 present smaller body proportions, and variation range of body height, while R. vulpinus is characterized by a shorter eye diameter. The Myomere number is a relevam feature for the idenlification of R. vulpinus larvae, since it is the Characiform that possesses the highest Myomere number, among those species of this family studied so far.
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Desenvolvimento inicial de larvas de Rhaphiodon vulpinus Agassiz (Characiformes, Cynodontidae) Initial development of Rhaphiodon vulpinus Agassiz larvae (Characiformes, Cynodontidae)
Sociedade Brasileira de Zoologia, 2002Co-Authors: Wilson Treger Zydowicz De Sousa, William SeveriAbstract:The cynodontid fish Rhaphiodon vulpinus Agassiz, 1829, known as "peixe-cachorro", is the only species of the family oceurring in the Pantanal of Mato Grosso. The initial development of its larvae was characterized, based on material collected with a 500 µm mesh size plankton-net, in several biotopes of the Pantanal of Barão de Melgaço, State of Mato Grosso, Central Brazil. The analysis was carried out with 72 larvae with standard length (SL) between 4.7 and 13.8 mm. The morphometric measurements varied positively with standard length, and body proportions ranged 8.1-17.8% for head length (HL), 6.2-10.1% for body height, and 63.673.5%, 16.8-21.6%, and 61.8-78.2% SL, respectively for pre-dorsal, pre-pectoral and pre-anal distances. The eye diameter varied positively with HL and its proportion varied between 9.1 -22.5% HL. The body relations did not show great variation along the larval development. The morphologicai characterization of larvae from 4.7 to 5.8 mm SL, in the pre-flexion phase, showed lhe presence of anembryonic finfold covering the unraycd fins, exposed branchial arches, absence of exogenous digestive content, unpigmented eyes and round shaped head. Larvae with SL between 8.1 and 13.8 mm SL were in the flexion phase, presenting a pointed head, mouth filled with externai and internai rows of numerous teeth, presence of exogenous food, pigmented eyes, branchial filaments still exposed, evident swimming-bladder, and formation of the first caudal, dorsal and anal fins' rays. Only individuais in the pre-flexion and flexion phases were analyzed, and no completely developed fin was evidenced. A maximum number of 69 Myomeres was counted and no evident pigmentation over the body observed. Comparing R. vulpinus larvae to those of other Characiformes, it was observed that this species and Apareiodon affinis Steindachner, 1879 present smaller body proportions, and variation range of body height, while R. vulpinus is characterized by a shorter eye diameter. The Myomere number is a relevam feature for the idenlification of R. vulpinus larvae, since it is the Characiform that possesses the highest Myomere number, among those species of this family studied so far
Johan L. Van Leeuwen - One of the best experts on this subject based on the ideXlab platform.
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Undulatory fish swimming: from muscles to flow
2016Co-Authors: Ulrike K. Müller, Johan L. Van LeeuwenAbstract:Undulatory swimming is employed by many fish for routine swimming and extended sprints. In this biomechanical review, we address two questions: (i) how the fish’s axial muscles power swimming; and (ii) how the fish’s body and fins generate thrust. Fish have adapted the morphology of their axial musculature for high power output and efficiency. All but the superficial muscle fibres are arranged along curved trajectories, and the Myomeres form nested cones. Two conflicting performance goals shape the fibre trajectories of the axial muscles. Maximum power output requires that all fibres contract uniformly. In a bending fish, uniform contraction in a single Myomere can be ensured by curved fibre trajectories. However, uniform strain is only desirable if all muscle fibres have the same contractile properties. The fish needs several muscle-fibre types that generate maximum power at different contraction speeds to ensure effective muscle power generation across a range of swimming speeds. Consequently, these different muscle-fibre types are better served by non-uniform contractions. High power output at a range of swimming speeds require
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Undulatory fish swimming: from muscles to flow
Fish and Fisheries, 2006Co-Authors: Ulrike K. Müller, Johan L. Van LeeuwenAbstract:Undulatory swimming is employed by many fish for routine swimming and extended sprints. In this biomechanical review, we address two questions: (i) how the fish's axial muscles power swimming; and (ii) how the fish's body and fins generate thrust. Fish have adapted the morphology of their axial musculature for high power output and efficiency. All but the superficial muscle fibres are arranged along curved trajectories, and the Myomeres form nested cones. Two conflicting performance goals shape the fibre trajectories of the axial muscles. Maximum power output requires that all fibres contract uniformly. In a bending fish, uniform contraction in a single Myomere can be ensured by curved fibre trajectories. However, uniform strain is only desirable if all muscle fibres have the same contractile properties. The fish needs several muscle-fibre types that generate maximum power at different contraction speeds to ensure effective muscle power generation across a range of swimming speeds. Consequently, these different muscle-fibre types are better served by non-uniform contractions. High power output at a range of swimming speeds requires that muscle fibres with the same contractile properties contract uniformly. The ensuing helical fibre trajectories require cone-shaped Myomeres to reduce wasteful internal deformation of the entire muscle when it contracts. It can be shown that the cone-shaped Myomeres of fish can be explained by two design criteria: uniform contraction (uniform strain hypothesis) and minimal internal deformation (mechanical stability hypothesis). So far, only the latter hypothesis has found strong support. The contracting muscle causes the fish body to undulate. These body undulations interact with the surrounding water to generate thrust. The resulting flow behind the swimming fish forms vortex rings, whose arrangement reflects the fish's swimming performance. Anguilliform swimmers shed individual vortex rings during steady swimming. Carangiform swimmers shed a connected chain of vortex rings. The currently available sections through the total flow fields are often not an honest representation of the total momentum in the water - the wake of carangiform swimmers shows a net backward momentum without the fish accelerating - suggesting that our current picture of the generated flow is incomplete. To accelerate, undulatory swimmers decrease the angle of the vortex rings with the mean path of motion, which is consistent with an increased rate of backward momentum transfer. Carangiform swimmers also enlarge their vortex rings to accelerate and to swim at a higher speed, while eel, which are anguilliform swimmers, shed stronger vortex rings
Wilson Treger Zydowicz De Sousa - One of the best experts on this subject based on the ideXlab platform.
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Desenvolvimento inicial de larvas de Rhaphiodon vulpinus Agassiz (Characiformes, Cynodontidae)
Revista Brasileira de Zoologia, 2002Co-Authors: Wilson Treger Zydowicz De Sousa, William SeveriAbstract:The cynodontid fish Rhaphiodon vulpinus Agassiz, 1829, known as "peixe-cachorro", is the only species of the family oceurring in the Pantanal of Mato Grosso. The initial development of its larvae was characterized, based on material collected with a 500 µm mesh size plankton-net, in several biotopes of the Pantanal of Barao de Melgaco, State of Mato Grosso, Central Brazil. The analysis was carried out with 72 larvae with standard length (SL) between 4.7 and 13.8 mm. The morphometric measurements varied positively with standard length, and body proportions ranged 8.1-17.8% for head length (HL), 6.2-10.1% for body height, and 63.673.5%, 16.8-21.6%, and 61.8-78.2% SL, respectively for pre-dorsal, pre-pectoral and pre-anal distances. The eye diameter varied positively with HL and its proportion varied between 9.1 -22.5% HL. The body relations did not show great variation along the larval development. The morphologicai characterization of larvae from 4.7 to 5.8 mm SL, in the pre-flexion phase, showed lhe presence of anembryonic finfold covering the unraycd fins, exposed branchial arches, absence of exogenous digestive content, unpigmented eyes and round shaped head. Larvae with SL between 8.1 and 13.8 mm SL were in the flexion phase, presenting a pointed head, mouth filled with externai and internai rows of numerous teeth, presence of exogenous food, pigmented eyes, branchial filaments still exposed, evident swimming-bladder, and formation of the first caudal, dorsal and anal fins' rays. Only individuais in the pre-flexion and flexion phases were analyzed, and no completely developed fin was evidenced. A maximum number of 69 Myomeres was counted and no evident pigmentation over the body observed. Comparing R. vulpinus larvae to those of other Characiformes, it was observed that this species and Apareiodon affinis Steindachner, 1879 present smaller body proportions, and variation range of body height, while R. vulpinus is characterized by a shorter eye diameter. The Myomere number is a relevam feature for the idenlification of R. vulpinus larvae, since it is the Characiform that possesses the highest Myomere number, among those species of this family studied so far.
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Desenvolvimento inicial de larvas de Rhaphiodon vulpinus Agassiz (Characiformes, Cynodontidae) Initial development of Rhaphiodon vulpinus Agassiz larvae (Characiformes, Cynodontidae)
Sociedade Brasileira de Zoologia, 2002Co-Authors: Wilson Treger Zydowicz De Sousa, William SeveriAbstract:The cynodontid fish Rhaphiodon vulpinus Agassiz, 1829, known as "peixe-cachorro", is the only species of the family oceurring in the Pantanal of Mato Grosso. The initial development of its larvae was characterized, based on material collected with a 500 µm mesh size plankton-net, in several biotopes of the Pantanal of Barão de Melgaço, State of Mato Grosso, Central Brazil. The analysis was carried out with 72 larvae with standard length (SL) between 4.7 and 13.8 mm. The morphometric measurements varied positively with standard length, and body proportions ranged 8.1-17.8% for head length (HL), 6.2-10.1% for body height, and 63.673.5%, 16.8-21.6%, and 61.8-78.2% SL, respectively for pre-dorsal, pre-pectoral and pre-anal distances. The eye diameter varied positively with HL and its proportion varied between 9.1 -22.5% HL. The body relations did not show great variation along the larval development. The morphologicai characterization of larvae from 4.7 to 5.8 mm SL, in the pre-flexion phase, showed lhe presence of anembryonic finfold covering the unraycd fins, exposed branchial arches, absence of exogenous digestive content, unpigmented eyes and round shaped head. Larvae with SL between 8.1 and 13.8 mm SL were in the flexion phase, presenting a pointed head, mouth filled with externai and internai rows of numerous teeth, presence of exogenous food, pigmented eyes, branchial filaments still exposed, evident swimming-bladder, and formation of the first caudal, dorsal and anal fins' rays. Only individuais in the pre-flexion and flexion phases were analyzed, and no completely developed fin was evidenced. A maximum number of 69 Myomeres was counted and no evident pigmentation over the body observed. Comparing R. vulpinus larvae to those of other Characiformes, it was observed that this species and Apareiodon affinis Steindachner, 1879 present smaller body proportions, and variation range of body height, while R. vulpinus is characterized by a shorter eye diameter. The Myomere number is a relevam feature for the idenlification of R. vulpinus larvae, since it is the Characiform that possesses the highest Myomere number, among those species of this family studied so far
