A superordem Batoidea é fortemente corroborada como monofilética, com cerca de 650 espécies viventes, sendo a superordem mais diversa dentre os Chondrichthyes. O órgão copulador duplo, conhecido como mixopterígio, é uma das sinapomorfias de Chondrichthyes. O mixopterígio de Batoidea, com exceção de Rajidae, não foi amplamente analisado do ponto de vista comparativo, sendo o conhecimento restrito a descrições isoladas de alguns táxons. O vasto conhecimento do mixopterígio de rajídeos evidencia a grande importância da estrutura em estudos de taxonomia e filogenia, com muitos táxons definidos principalmente baseados na anatomia e morfologia dos componentes que formam o órgão copulador. Os demais grupos carecem de estudos comparativos como feitos para Rajidae. Devido à importância sistemática do mixopterígio em Rajidae, o presente projeto tem objetivo descrever as estruturas internas e externas que compõem o órgão copulador dos membros das famílias de Batoidea, identificar possíveis padrões anatômicos que caracterizam grupos taxonômicos e testar o monofiletismo da superordem Batoidea e de seus principais grupos. A terminologia utilizada para os componentes do órgão copulador é praticamente toda baseada na família Rajidae, sendo necessária uma revisão abordando os demais grupos de raias e seus táxons proximamente relacionados / Batoidea is a monophyletic group and is the most diverse superorder within Chondrichthyes with about 640 valid species. Endoskeletal copulatory organs in males (claspers) are a synapomorphy of Chondrichthyes. The classification as well as interrelationships within elasmobranchs has been influenced by characters found in the copulatory organs. In Rajiformes (skates), for example, the claspers are very important in phylogenic and taxonomic studies, with most genera and species defined based on the anatomy of clasper elements, especially those of the terminal group (dorsal and ventral terminal cartilages). However in other batoids the anatomy and morphology of the claspers are still precariously known, highlighting the necessity of a thorough morphological analysis of the copulatory organs of Batoidea. The present PhD project, therefore, is a thorough, detailed morphological and systematic analysis of the variation observed in claspers among all batoid groups. The main objective of the present project is to describe and compare the external and internal (muscle and skeleton) components of the clasper, clarifying relationships of homology of its components among batoids, and discovering systematic patterns that are plylogenetically informative that may aid in resolving problematic relationships within batoids (such as which batoid group is most basal, elucidate the doubtful monophyletic status of guitarfishes, and the phylogenetic position of problematic taxa, such as Zanobatus, Platyrhinidae and electric rays)

A classe Chondrichthyes compreende cerca de 1100 espécies divididas em duas subordens, Holocephali (quimeras) e Elasmobranchii (tubarões e raias). O monofiletismo da classe é sustentado pela calcificação prismática do esqueleto, presença de clásper pélvico, substituição periódica das fileiras dentárias. Porém, as interrelações em Elasmobranchii não estão claras. Duas hipóteses estão em discussão atualmente. A primeira delas, baseada em dados morfológicos, apresenta dois grandes grupos de tubarões, Galeomorphii e Squalomorphii, sendo que as raias (Batoidea) aparecem como espécies derivadas no segundo grupo. A segunda hipótese, baseada em dados moleculares, sugere que Galeomorphii e Squalomorphii forme um clado monofilético e que seja grupo-irmão de Batoidea. Portanto, a dúvida sobre o monofiletismo dos tubarões ainda persiste. Para tentar elucidar esta questão, este trabalho abordou a anatomia comparada dos músculos dos arcos maxilar e hióide de 98 espécies, pertencentes a 37 famílias, de tubarões, raias e quimeras. A musculatura de todas as espécies foi descrita, servindo de base para comparações entre as famílias. No total 35 caracteres são propostos, a partir de informações revisadas da bibliografia e das muitas observações, e devem ser testados em uma matriz de dados já existente. Os caracteres foram discutidos de acordo com questões filogenéticas dentro da subclasse Elasmobranchii, abordando problemas como a relação entre Orectolobiformes e Heterodontiformes, a relação entre Chlamydoselachus e Hexanchidae, o monofiletismo em Squaliformes, as discussões sobre o grupo Hypnosqualea e as relações entre Potamotrygonidae e as demais raias / The class Chondrichthyes comprises about 1110 species in two subclasses, Holocephali (chimaeras) and Elasmobranchii (sharks and rays). The monophyly of this class is supported by prismatic calcification of the skeleton, presence of pelvic claspers, substitution of teeth in dental rows. However, interrelationships within Elasmobranchii are not clear, with two principal hypotheses discussed. The first one, based on morphological data, presents two groups of sharks, Galeomorphii and Squalomorphii, and rays (Batoidea) are considered to have derived within the second group. The second hypotheses, based on molecular data, suggest Galeomorphii and Squalomorphii as a monophyletic clade, sister-group to Batoidea. Therefore, the question about the monophyly of sharks persists. To try to elucidate this issue, the present work examined the comparative anatomy of muscles of jaws and hyoid arches of 97 species, belonging to 37 families of sharks, rays and chimaeras. The musculature of all species was described, serving as a basis for comparisons among the families. A summary of 35 myological characters are proposed, based on information acquired from the literature and on personal observations, and should be tested in the context of a character matrix analyzed in a phylogenetic parsimony analysis. The characters described were discussed addressing the main phylogenetic questions within the subclass Elasmobranchii, regarding, for example, the relationship between Heterodontiformes and Orectolobiformes, the relationship between Chlamydoselachus and Hexanchidae, the monophyly of Squaliformes, the monophyly of Hypnosqualea, and the intrarelationships of potamotrygonid stingrays

Desde o século XIX a diversidade taxonômica e os hábitos dos representantes do gênero Toxodon sempre geraram muitas discordâncias. Cerca de 30 espécies nominais foram atribuídas ao gênero, muitas delas com base apenas em fragmentos isolados. Os toxodontes sempre foram considerados animais de hábitos semiaquáticos semelhantes aos atuais hipopótamos. Considerando sua rica megafauna, a América do Sul pleistocênica deveria ser muito semelhante ao atual continente africano. Assim, com o objetivo de contribuir com uma nova visão para a diversidade e hábitos dos toxodontes, foi realizado um extenso estudo de anatomia comparada dos toxodontes com os mamíferos de grande porte daquele continente. Diferentes elementos ósseos foram utilizados, tais como crânio, mandíbula, vértebras, úmero, rádio, ulna, fêmur, tíbia, fíbula, astrágalo e calcâneo. Observa-se pela morfologia do crânio, das vértebras e dos membros anteriores que os toxodontes deveriam ter hábitos muito mais semelhantes aos rinocerontes do que aos hipopótamos modernos. Esta hipótese permite uma nova visão sobre a diversidade dos toxodontes, com base no estudo das variações morfológicas que podem ocorrer em animais simpátricos e sintópicos, tais como os rinocerontes africanos (Ceratotherium simum e Diceros bicornis). A variabilidade osteológica intraespecífica observada nestes animais alerta para a determinação equivocada de um grande número de espécies fósseis alocadas em um único gênero. O longo período de ocorrência do gênero Toxodon nos estratos favorece a consideração de espécies cronológicas como Toxodon chapalmalensis (Plioceno) e Toxodon ensenadensis (Pleistoceno Inferior). No Pleistoceno Superior afere-se a presença de Toxodon platensis e Toxodon gracilis. A espécie Toxodon burmeisteri representa uma variação morfológica de Toxodon platensis. Outras duas espécies de toxodontes, Trigodonops lopesi e Mixotoxodon larensis, tiveram distribuição mais setentrional que as demais e teriam hábitos alimentares distintos daqueles de Toxodon platensis devido à morfologia craniana. / Since the 19th Century the taxonomic diversity and habit of the representatives of the genus Toxodon have been a source of controversy. Around 30 named species have been attributed to the genus, many based solely on isolated fragments. The toxodonts have always been considered as animals with a semi-aquatic habit rather like the modern hippopotamus. Considering its rich megafauna, South America in the Pleistocene was probably very similar to the present-day African continent. Thus, with the aim of providing new insights into the diversity and habit of the toxodonts, a comparative anatomical study was made of this group vis-a-vis the large-sized mammals of Africa. Different bone elements were used, such as the cranium, mandible, vertebrae, humerus, radius, ulna, femur, tibia, fibula, astragalus and calcaneus. It was concluded from the cranial, vertebral and fore-limb morphology that toxodonts must have had a habit more similar to that of the rhinoceroses than to the hippopotamuses. This hypothesis permits a new viewpoint for the diversity of the toxodonts, based on a study of the morphological variations that may occur in sympatric and syntopic animals, such as the African rhinoceroses (Ceratotherium simum and Diceros bicornis). The intra-specific variation in bone form found in these animals suggests the likely mistaken attribution of a large number of fossil species that have been allocated to a single genus. The long persistence in the fossil strata of the genus Toxodon allows us to consider chronological species such as Toxodon chapalmalensis (Pliocene) and Toxodon ensenadensis (Lower Pleistocene). In the Upper Pleistocene occur Toxodon platensis and Toxodon gracilis. The species Toxodon burmeisteri represents a morphological variant of Toxodon platensis. Two other toxodont species, Trigodonops lopesi and Mixotoxodon larensis, had a more northerly distribution than the others, and they also had different diets from that of Toxodon platensis according to their cranial morphology.

A classe Chondrichthyes compreende cerca de 1100 espécies divididas em duas subordens, Holocephali (quimeras) e Elasmobranchii (tubarões e raias). O monofiletismo da classe é sustentado pela calcificação prismática do esqueleto, presença de clásper pélvico, substituição periódica das fileiras dentárias. Porém, as interrelações em Elasmobranchii não estão claras. Duas hipóteses estão em discussão atualmente. A primeira delas, baseada em dados morfológicos, apresenta dois grandes grupos de tubarões, Galeomorphii e Squalomorphii, sendo que as raias (Batoidea) aparecem como espécies derivadas no segundo grupo. A segunda hipótese, baseada em dados moleculares, sugere que Galeomorphii e Squalomorphii forme um clado monofilético e que seja grupo-irmão de Batoidea. Portanto, a dúvida sobre o monofiletismo dos tubarões ainda persiste. Para tentar elucidar esta questão, este trabalho abordou a anatomia comparada dos músculos dos arcos maxilar e hióide de 98 espécies, pertencentes a 37 famílias, de tubarões, raias e quimeras. A musculatura de todas as espécies foi descrita, servindo de base para comparações entre as famílias. No total 35 caracteres são propostos, a partir de informações revisadas da bibliografia e das muitas observações, e devem ser testados em uma matriz de dados já existente. Os caracteres foram discutidos de acordo com questões filogenéticas dentro da subclasse Elasmobranchii, abordando problemas como a relação entre Orectolobiformes e Heterodontiformes, a relação entre Chlamydoselachus e Hexanchidae, o monofiletismo em Squaliformes, as discussões sobre o grupo Hypnosqualea e as relações entre Potamotrygonidae e as demais raias / The class Chondrichthyes comprises about 1110 species in two subclasses, Holocephali (chimaeras) and Elasmobranchii (sharks and rays). The monophyly of this class is supported by prismatic calcification of the skeleton, presence of pelvic claspers, substitution of teeth in dental rows. However, interrelationships within Elasmobranchii are not clear, with two principal hypotheses discussed. The first one, based on morphological data, presents two groups of sharks, Galeomorphii and Squalomorphii, and rays (Batoidea) are considered to have derived within the second group. The second hypotheses, based on molecular data, suggest Galeomorphii and Squalomorphii as a monophyletic clade, sister-group to Batoidea. Therefore, the question about the monophyly of sharks persists. To try to elucidate this issue, the present work examined the comparative anatomy of muscles of jaws and hyoid arches of 97 species, belonging to 37 families of sharks, rays and chimaeras. The musculature of all species was described, serving as a basis for comparisons among the families. A summary of 35 myological characters are proposed, based on information acquired from the literature and on personal observations, and should be tested in the context of a character matrix analyzed in a phylogenetic parsimony analysis. The characters described were discussed addressing the main phylogenetic questions within the subclass Elasmobranchii, regarding, for example, the relationship between Heterodontiformes and Orectolobiformes, the relationship between Chlamydoselachus and Hexanchidae, the monophyly of Squaliformes, the monophyly of Hypnosqualea, and the intrarelationships of potamotrygonid stingrays

Calretinin (CR) and parvalbumin (PV) neurons are inhibitory interneurons (INs) that play important roles in the modulation of excitatory pyramidal neurons. They are found in many species are and throughout the neocortex. However, their characteristics vary between species and brain region. The aim of this study was to compare the density, distribution, and inhibitory signaling of CR and PV neurons in monkey primary visual cortex (V1), monkey lateral prefrontal cortex (LPFC), mouse V1 and mouse frontal cortex (FC). Coronal brain slices from each of the species and brain regions were stained using immunohistochemistry and then the slices were scanned using high-resolution confocal imaging. High resolution image stacks were used to count the somata of CR and PV. The vesicular gamma aminobutyric acid (GABA) transporter (VGAT), CR and PV particles were analyzed to quantify these inhibitory markers in monkey V1, LPFC, and mouse V1 and FC. There were significant differences in the laminar distribution of CR and PV neurons in that CR neurons were concentrated in L2/3 and PV neurons were concentrated in L2-5. In L2/3, Monkey V1 had more CR neurons than did monkey LPFC. Furthermore, there were a greater number of PV neurons in monkey and mouse V1 compared to monkey LPFC and mouse FC. In L2/3, monkey V1 had the highest number of PV neurons. In L5, there significantly greater PV neurons in mouse V1 compared to monkey V1. There was significantly higher density of CR neurons in the upper middle layers of Monkey V1 compared to mouse V1 and monkey LPFC compared to mouse FC. The upper middle layers of monkey V1 had significantly higher density of PV neurons compared to monkey LPFC and mouse V1. There was significantly higher density of VGAT particles in monkey V1 and LPFC compared to mouse V1 and FC, which indicates more inhibitory synapses. There were significantly more VGAT+ boutons colocalized with PV+ boutons than CR+ boutons. Finally, discriminant analysis and hierarchical cluster analysis show that species is the largest separating factor between monkey V1, LPFC and mouse V1 and FC. Mouse V1 and FC are very similar, and monkey V1 and LPFC are dissimilar from one another. This data, united with comparative data on pyramidal neurons, demonstrates that neurons have differences between species, and monkeys have more regional specialization than mice.

Tetrapods water-to-land transition in the Devonian was accompanied by an array of morphological modifications aiding in locomotion and food acquisition, which included diversification in teeth morphology. Different teeth morphology allowed tetrapods to take advantage of different ecological niches through food specialization. As useful as teeth are, we can see the repeated development of edentulous (=toothless) system throughout the fossil record, most frequently in Archosauria. Archosauria, represented today by living crocodylians and birds and includes extinct non-avian dinosaurs and pseudosuchians, first appeared in the early Mesozoic Era, during the Middle Triassic. Archosauria continue to diversify through the rest of the Mesozoic Era and during that time, we see a plethora of modifications made to the feeding apparatus in this group, such as dental batteries in hadrosaurids, bone crushing teeth in tyrannosaurids, or edentulous jaws covered in a rhamphotheca (=beak) in oviraptors. In the fossil record, morphological modifications can be seen in fossilized skeletal remains, but this is an incomplete picture of a living organism. The skeletal system of an organism is the housing and support, and it is powered by the muscles and ligaments and ultimately controlled by the nervous system. Without the soft tissues, we recognize that there are missing gaps in the anatomy, and modern organisms have been studied as analogs to fill these gaps. Traces of soft tissue are not completely undetectable in the fossil record. In exceptional preservation sites, materials such as keratinous integuments and gut materials have been found, but more commonly, we utilize osteological correlates such as muscle attachment scars that are derived from studying modern homologs to make inference about the presence of soft tissues. One advantage of using modern analogs to study soft tissue morphology is that we are able to incorporate how the targeted morphology grows through the observable developmental timescale. Ontogeny, or prenatal development and postnatal growth, has been utilized as an approach to understand how millions of years of natural selection affected the phenotypic expression in an organism. Through improvement of technology and laboratory techniques such as CT scanning and contrast-enhanced staining, in situ anatomical studies have revealed more information and details about the soft-tissue morphology in modern organisms to improve our interpretation of fossil organisms and address broader morphological macroevolution questions. This dissertation focuses on the construction and ontogenetic changes in the soft tissue (i.e., jaw muscles and keratinous sheath or rhamphotheca) and skeletal morphology of the avian edentulous feeding system and apply it to extinct edentulous feeding system across reptiles. My first chapter describes the ontogenetic changes in the musculoskeletal system of the jaws of emus (Dromaius novaehollandiae) to make inferences about potential influences of feeding function on the feeding apparatus during development. I combined microCT scanning, including contrast-stained CT scanning, and 3D geometric morphometric analyses to explore how the feeding apparatus changes through ontogeny and highlight intraspecific complexity within skeletally immature individuals. The second chapter explores the keratin layers making up the simple rhamphotheca of the chicken (Gallus gallus domesticus) and documents the varying mechanical properties within a single rhamphothecal sheath. This chapter establishes that biomechanical functions such as food and object manipulation affect the keratinous sheathing that covers the avian jaw bones by potentially selecting for specific regions of the rhamphotheca to be more mechanically resistant than others. In the third chapter, I review osteological correlates for rhamphotheca in modern edentulous taxa, birds and turtles, and in the extinct taxon, Trilophosaurus buettneri, a Late Triassic archosauromorph that was proposed to have both a beak and transversely-oriented teeth, to determine whether T. buettneri had a rhamphotheca and if so to what extent. This chapter reveals that one of the osteological correlates, foramina patterns, will benefit from future study that incorporates more turtle species and establishes that lack of wear on the oral/occlusal edge might be a valid osteological correlate to use for future fossil examination. These chapters showed a possible underlying influence of the feeding biomechanical function onto the anatomical construction and ontogeny in both the modern edentulous feeding system, providing an avenue for further exploration to address the repeated development of the edentulous feeding system. / Doctor of Philosophy / How an animal obtained and processed food has been changing since animals first started to come onto land in the Devonian. One major development in how animals feed was the development of teeth, which function as versatile tools that can help crush and tear food items up and give animals the ability to eat a variety of food items. As useful as teeth are, however, we can find many animal lineages repeatedly lose some or all of their teeth permanently and gained a beak. Many of these lineages are found within Archosauria, which are represented by living crocodylians and birds and extinct lineages like pterosaurs and non-avian dinosaurs, have existed since the Middle Triassic (252 to 201.5 million years ago). Archosaurs saw a major rise and fall in the number of lineages through the Mesozoic Era. These archosaurian lineages were diverse in how they obtained and processed food, which included bone crushing teeth in tyrannosaurs, dental batteries in hadrosaurs, and beaks (toothless jaws covered in keratin sheathing) in oviraptors. The fossil record can tell us about the changes to the bony structure of these extinct archosaurs, but an organism is made of more than just their bones. In vertebrates, movements are powered by the muscles and ligaments attached to them and controlled by the nervous system. In the fossil record, that soft-tissue information is often lost except in exceptionally preserved fossils. However, we can use bony correlates, indicators on the surface of the bones for the presence of a particular soft tissue, to interpret the missing soft tissues of fossils. In order for us to study soft tissue information in an extinct species, we can utilize living organisms as a model. One advantage in studying modern organisms is that we can watch the soft and hard tissues grow through their lifetime and document changes in shape and size of particular features. Growth and development, or ontogeny, is one way to see how millions of years of evolution can affect the how an animal look like. With new technology such as CT scanning, studying the soft and hard tissues in tandem has revealed new information and allowed us to improve our understanding of how different parts of an animal function, but also make better inferences of how extinct animals were built. This dissertation focuses on exploring the anatomy and growth of features making up the jaws of beaked animals, the jaw muscles, the bones to which they attach, and the keratin sheaths covering them. Chapter one focused on a growth series of emu skulls to look at how bones and jaw muscles develop and how they are linked together. This chapter documents changes in shape and size of the bones and muscles to understand factors that can affect their growth. Chapter one also highlights more complexity in younger specimens that should be explored in future research. The second chapter looked at the various keratin layers that make up the rhamphothecae, or keratin sheaths, that cover the jaw bones in a beak. This chapter tested whether functions like grabbing food and other objects affects the hardness of the rhamphotheca in chickens. In chapter three, I examined three bony correlates that are used to infer the presence of a rhamphotheca in modern archosaurs (birds and turtles) and a stem archosaur called Trilophosaurus buettneri to determine if T. buettneri had a rhamphotheca. This chapter helped establish the validity of old and new bony correlates and determine that at least one of the bony correlates needs more sampling in modern taxa for stronger comparison and linkage of morphology between the modern and extinct taxa. These three chapters showed that the mechanical function of feeding can influence the anatomy toothless feeding system and how the system develops through growth, which can be a way for us to address how the toothless feeding system continuously developed in the fossil record.

Arthropods are the most species-rich group of animals, and as such they exhibit an amazing diversity of morphological, behavioral, and ecological adaptations. Because of this diversity, the evolutionary history of this group has been, and still is notoriously difficult to determine because considerations of different traits invariably support alternative evolutionary relationships. Their nervous systems provide an invaluable set of characters for systematic inferences about the origins and evolutionary trajectories of Arthropoda. This is because nervous systems are ubiquitous and contain a wealth of structures from which to infer shared ancestry. Considerations of ancestral arthropod relationships have further provided insights into how arthropod nervous systems have maintained some traits through evolutionary time and how others have been modified or acquired as novelties. This dissertation explores the evolution of arthropod brains within an interdisciplinary framework, utilizing comparative neuroanatomical, neural cladistic, and molecular phylogenetic analyses to support novel hypotheses of nervous system evolution in arthropods. The field of neurophylogenetics relies on the characterization of shared derived neural traits to infer ancestry amongst taxa. The first portion of this work describes highly conserved neural elements from the lamina, or first optic neuropil, of several crustaceans. This study is followed by a neural cladistic study that infers evolutionary relationships amongst major arthropod groups based solely on neural traits. The results of this study are then compared to those from a large-scale molecular phylogenomic analysis of hundreds of conserved orthologous genes. Results from neural cladistic and molecular phylogenetics suggest several species whose neuroanatomical characterization would provide support for novel evolutionary hypotheses. The last portion of this dissertation details a comparative neuroanatomical study on one such diagnostic taxa, the copepod Tigriopus californicus. Two principles of arthropod nervous system organization and evolution are repeatedly supported with this approach: 1) many complex neural structures shared amongst arthropod groups have been inherited from ancient common ancestors, suggesting that the neural arrangements seen today have been carried over from antiquity; and 2) these same complex attributes are absent in numerous late-diverging lineages, supporting the hypothesis that secondary simplification of nervous systems is a common property of arthropods.

Segundo Savitzky (1974) e Ferrarezzi (1994b), a tribo Nothopsini é composta pelos gêneros Diaphorolepis, Emmochliophis, Nothopsis, Synophise Xenopholis, contabilizando um total de doze espécies reconhecidas atualmente e distribuídas pelas Américas Central e do Sul. Embora hajam estudos especificamente dirigidos aos gêneros de Nothopsini, e outros que proporcionam hipóteses filogenéticas, as relações filogenéticas destes gêneros continuam alvo de debates, tendo os cinco gêneros de Nothopsini sido relacionados a diferentes grupos (Acrochordidae, Xenodontinae, Natricidae, Amastridinae, Dipsadinae e Xenodermatinae), por diferentes autores. Atualmente, os Nothopsini são definidos como gêneros incertae sedis dentro da subfamília Dipsadinae (Zaher, 1999). Com base no exame morfológico de material biológico e imagens ct-scan, neste trabalho foram comparadas a anatomia craniana, vertebral e hemipeniana das espécies Diaphorolepis wagneri, Nothopsis rugosus, Synophis bicolor, Amastridium veliferum, Chersodromus liebmanni, Ninia atrata, N. sebae, Xenopholis scalaris e X. undulatus. Objetivando posicionar os gêneros estudados num contexto mais amplo realizou-se uma análise filogenética preliminar com base na definição de 77 caracteres correspondentes à morfologia do complexo palatomaxilar, do suspensorium, mandíbula, dos ossos frontais, dos pós-orbitais, das vértebras e dos hemipênis das espécies estudadas de Nothopsini, além de 37 gêneros da família Dipsadidae, e usando Thamnophis elegans como grupo externo. Os resultados da anatomia comparada e da análise filogenética preliminar redefinem a tribo Nothopsini como formada pelos gêneros Diaphorolepis, Nothopsis e Synophis, posiciona o gênero Xenopholis na subfamília Dipsadinae e sugere uma relação próxima entre o gênero Xenopholis e os demais nothopsíneos. Já o gênero Emmochliophis é alocado dentro da subfamília Dipsadini, porém este posicionamento é visto com ressalvas até que mais análises sejam conduzidas. Ademais, são identificados dois padrões morfológicos, um compartilhado pelas espécies do gênero Ninia e Chersodromus liebmanni, e outro compartilhado entre Amastridium veliferum, Nothopsis rugosus, Diaphorolepis wagneri, Synophis e Xenopholis. / The tribe Nothopsini is composed by 12 currently recognized species from the genera Diaphorolepis, Emmochliophis, Nothopsis, Synophis and Xenopholis (Savitzky, 1974; Ferrarezi, 1994b) that are distributed throughout Central and South America. Although several studies addressed the Nothopsini, their phylogenetic affinities are still unresolved, with several author presenting distinct phylogenetic hypotheses for the five genera of Nothopsini. Currently, the genera assigned to the tribe Nothopsini are considered as incertae sedis within the Dipsadinae (Zaher, 1999). The present study is based on a morphological examination of biological material and ct-scan imaging that aims to compare the cranial, vertebral and hemipenial anatomy of Diaphorolepis wagneri, Nothopsis rugosus, Synophis bicolor, Amastridium veliferum, Chersodromus liebmanni, Ninia atrata, N.sebae, Xenopholis scalaris e X.undulatus. A preliminary phylogenetic analysis was performed, based on 77 characters derived from the palatomaxillary and suspensorium complexes, mandible, frontal bones, post-orbital bones, vertebrae and hemipenes of the studied species of Nothopsini, 37 additional Dipsadidae genera, and Thamnophis elegans to root the analysis. The results achieved by the comparative anatomy and the phylogenetic analysis redefines the tribe Nothopsini as composed by the genera Diaphorolepis, Nothopsis e Synophis, places the genus Xenopholis within the subfamily Dipsadinae and suggests a close relationship between Xenopholis and the Nothopsini. The genus Emmochliophis is allocated within the Dipsadini, but this placement must be considered with some caution until a more thorough analysis can be performed. Moreover, two morphological patterns are identified within the group under study, one shared by the species of the genus Ninia and Chersodromus liebmanni, and another shared by the species Amastridium veliferum, Nothopsis rugosus, Diaphorolepis wagneri, and the genera Synophis and Xenopholis.

Primary taxonomic research in neotropical ichthyology still suffers from limited integration between morphological and molecular tools, despite major recent advancements in both fields. Such tools, if used in an integrative manner, could help in solving long-standing taxonomic problems. The genus Pimelodella Eigenmann & Eigenmann, 1888 is a perfect case for an integrative and multidisciplinary approach in taxonomy. Pimelodella is a genus of the Heptapteridae broadly distributed throughout trans- and cis-Andean South America, and one of the main components of Neotropical Ichthyofauna. Nowadays is the most species-rich genus of the family, with 79 valid species. However, the validity and delimitation of those species is extremely problematic, due their broad geographic distribution, conserved morphology, and ancient and imprecise descriptions. Pimelodella is undoubtedly one of the most severe taxonomic bottlenecks in neotropical ichthyology. This project presents a taxonomic revision of Pimelodella using an integrative morphological-molecular approach. The traditional taxonomic revision covers the genus in its entirety, with all the components of this kind of study. All types were examined, and the number of valid species herein recognized was reduced to 55 species, for which full descriptions are presented. The molecular taxonomy was done for a circumscribed subset of the genus, with representation enough to understand the molecular divergences and compare them with the traditional taxonomy results, allowing an evaluation of the results of the revision. / A pesquisa taxonômica primária ainda apresenta pouca integração entre as ferramentas morfológicas e moleculares para o estudo de peixes neotropicais, apesar de grandes avanços recentes em ambos os campos. Tais ferramentas, se usadas de maneira integrativa, poderiam solucionar grupos reconhecidos por representarem problemas taxonômicos renitentes. O gênero Pimelodella Eigenmann & Eigenmann, 1888 se enquadra como um ótimo caso para a aplicação de uma estratégia integrativa e multidisciplinar. Pimelodella é um gênero da família Heptapteridae, distribuído amplamente por drenagens sul-americanas trans- e cis-andinas e compreende um dos principais componentes da ictiofauna neotropical. Atualmente é reconhecido como o maior gênero da família, com 79 espécies válidas descritas. Entretanto, a validade e delimitação dessas espécies é problemática, devido à elevada diversidade do gênero, aliada à ampla distribuição, morfologia conservada e descrições antigas e imprecisas. Trata-se de um dos grandes gargalos taxonômicos na sistemática e taxonomia de peixes neotropicais. Este projeto apresenta uma revisão taxonômica de Pimelodella utilizando uma abordagem integrativa morfológica-molecular. A revisão taxonômica clássica cobre a integridade da diversidade do gênero, com todos os componentes deste tipo de estudo. Todos os tipos foram examinados, e o número de espécies validas é aqui reduzido para 55 espécies, para as quais descrições completas são apresentadas. A parte molecular foi realizada em um subgrupo delimitado, com diversidade suficiente para que as estimativas de divergência molecular pudessem ser comparadas aos resultados da revisão morfológica, fornecendo um modelo de avaliação para o restante da revisão.

A família Carangidae Rafinesque 1815 (Teleostei: Percomorphacea: Carangiformes) é tradicionalmente reconhecida como um grupo monofilético, tanto em hipóteses baseadas em dados moleculares quanto morfológicos. O monofiletismo do grupo, entretanto, é sustentado por um baixo número de sinapomorfias e suas relações internas ainda apresentam conflitos. O status filético e inter-relações das tribos Trachinotini,Scomberoidini, Naucratini e Caranginivariam de acordo com autores e metodologias empregadas na reconstrução evolutiva da família. As propostas morfológicas mais recentes para os Carangidae datam de 30 anos atrás e empregam maciçamente dados de morfologia externa e osteologia, sendo a miologia do grupo praticamente inexplorada. O presente estudo analisou extensamente a miologia facial, gular e das nadadeiras peitorais, pélvicas e caudal dos Carangidae e grupos proximamente relacionados. Novos caracteres de origem miológica foram levantados e analisados sob um paradigma cladístico em conjunto com os demais caracteres morfológicos disponíveis na literatura especializada. Uma nova hipótese filogenética foi proposta e comparada com as disponíveis, tanto baseadas em dados morfológicos como moleculares. Os novos dados miológicos reforçam as hipóteses de monofiletismo das tribos de Carangidae, bem como a presença de dois grandes clados irmãos, um formado por Trachinotinie Scomberoidinie outro por Caranginie Naucratini. O estudo da musculatura também forneceu pistas sobre o posicionamento do historicamente problemático gênero Parastromateus dentro de Carangini. Além disso, a descrição de complexos musculares nunca antes estudados forneceu dados sobre o a evolução de músculos considerados erráticos em Percomorphacea e que podem contribuir para o entendimento das inter-relações deste grande grupo. / The Carangidae Rafinesque 1815 (Teleostei: Percomorphacea: Carangiformes) is traditionally recognized as a monophyletic group in both morphological and molecular hypotheses. The monophyly of the family, however, is supported by a surprisingly low number of synapomorphies and the internal resolution of the group is contentious. The phyletic status and interrelationships of the tribes Trachinotini, Scomberoidini, Naucratini, and Carangini vary across different studies. The most recent morphological hypothesis for carangids dates back to 30 years and is based solely on data from osteology and external morphology. The myology of the family remainednearly unexplored. The present study analyzed the facial, gular,pectoral, pelvic, and caudal muscles of carangids and closely related outgroups. Several characters from myology were discovered and analyzed under a cladistic paradigm. The new myological data were combined with the morphological data available in the literature in order to produce more robust and up to date phylogenetic hypotheses. The four traditional carangid tribes are herein recognized as monophyletic and the family is basally divided into two major sister clades: one comped by Trachinotini and Scomberoidini and another by Carangini and Naucratini. Also, the historically problematic genus Parastromateus was allocated intoaapical clade within the Carangini. The study of the fin musculature provided insights on the occurrence of muscles considered erratic across the Percomorphacea. Those new discoveries might be helpful for a better understanding of the phylogenetic relationships of thatlarge group.