This project aims to study fossil amphibian and reptile (herpetofaunal) remains from Quaternary sites in the British Isles. This neglected group of vertebrates hold great potential for Quaternary Science. Collectively, they cover a wide range of ecological tolerances, although individual species often have very specific tolerances. The biology and ecology of individual species are discussed (Chapter 2) to facilitate their use in Quaternary palaeoenvironmental reconstructions, and an account of previous work on fossil herpetofaunas is given (Chapter 3). Very little work on fossil herpetofaunas has been carried out in the British Isles, mainly due to a lack of the required osteological expertise. The preparation and study of a modern osteological collection (Chapter 4), for comparative purposes, has therefore constituted a large and essential part of the project. The resulting manual for the identification of fossil herpetofaunal remains, appropriately illustrated with SEMs and hand-drawn figures, is presented (Chapter 5). The difficulties encountered in identifying some taxa are discussed in detail, and points of caution are stressed where necessary.

Au cours des dernières décennies, d'énormes quantités de haies, de lisières ont étédétruites en Europe tandis que le régime des incendies majeurs augmente dans les milieuxméditerranéens. La perte de ces milieux de type lisières s'accompagne d'une chutecatastrophique de la biodiversité. Notamment par la perte des refuges disponibles pour lafaune. Cette thèse s'intéresse à l'importance des abris à différentes échelles et sur différentsmodèles biologiques. Premièrement, l'influence de la disponibilité en abris au pied des haiessur la biodiversité a été démontrée à l'aide d'inventaires et grâce à une expérimentation surle terrain. Pour cela, une nouvelle approche d'inventaire qui combine les avantages desinventaires rapides et des techniques non létales a été mise au point. A une échelleintermédiaire, l'impact positif de l'ouverture du milieu forestier sur des populations dereptiles a été mis en évidence. Enfin, un suivi au niveau individuel de tortues d'Hermann apermis de suivre les conséquences de modifications l'habitat suite à un incendie majeur ; ilsuggère que les habitats brûlés restent favorables sur le long terme.En conclusion, l'importance des abris pour la biodiversité a été démontrée à plusieurséchelles d'espace, de temps et de précision. La conséquence pratique est que les fichestechniques de gestion des haies et des lisières devraient en tenir compte, ce qui n'est pas lecas actuellement. / During the last decencies, massive amounts of hedgerows and forest hedges have beendestroyed in Europe whereas increasing fire regimes threatened Mediterranean habitats.The loss of these hedge habitats is concomitant to a drastic loss of biodiversity. Notablythrough the decrease of shelter available to the fauna. This thesis aims to investigate therole of refuges considering different scales and biological systems. First, the positiveinfluence of the availability of shelter at the base of hedgerows on biodiversity has beendemonstrated using surveys and a field experiment. For that, a novel technique has beendeveloped by combining the advantages of rapid biodiversity assessments with non-lethalprocedures. At an intermediary scale, the positive impact of habitat opening on ophidianpopulations has been shown in a forest context. Finally, individual monitoring of Hermanntortoises allowed us to examine the impact of a major fire in habitat changes; the resultssuggest that burnt habitats remain suitable on the long term.In conclusion, the importance of refuges on biodiversity have been demonstrated atdifferent time, spatial and accuracy scales. In practice, technical recommendations shouldtake into account this key element to manage hedgerows and other hedge habitats; thiscurrently not the case.

The osteology of the Upper Triassic podokesaurid Syntarsus rhodesiensis is described, based on a series of 30+ individuals representing all skeletal elements, recovered since the description of the holotype (Raath, 1969). A brief account of the geology of the finds is given, with an attempt at a reconstruction of the palaaoenvironment. The excellence of preservation of the bones has permitted an attempt at the restoration of soft tissues including the brain, cranial nerves, main cranial blood vessels and the musculature of the jaws, neck and limbs. Histological sections of limb bones have shown that the compact bone was highly vascular, and this, together with the structure of the brain, palaeoenvironmental considerations, social behaviour and group structure, leads to the conclusion that Syntarsus was an endothermic homeotherm inhabiting a hot arid region at the end of the Triassic, with a social organisation into "flocks" in which females predominated numerically. Clear evidence of sexual dimorphism is presented. Syntarsus is reconstructed as a bipedal, saltatorial predator which differs in subtle, but probably generically significant, characteristics from the closely related North American genus, Coelophysis. Its anatomy characterises it as a medium-sized agile animal with a highly kinetic skull; incipiently opposable pollex in the raptorial manus; highly cursorial hindlimb; and with features in the dentition and hallux which suggest a grooming function. It is concluded that the Triassic coelurosaurian stock provided an advanced and well adapted base from which the successful coelurosaur radiation into the later Mesozoic sprang, and that this stock was physiologically pre-adapted for the emergence of the avian (and possibly the pterosaur) lineages in the Jurassic

Las lagartijas Dicrodon guttulatum Duméril y Bibron, 1839 y Dicrodon holmbergi Schmidt 1957, conocidas como "cañanes", revisten importancia histórica y económica dado que son tradicionalmente consumidas por los pobladores de la costa norte del Perú desde tiempos precolombinos. Algunos investigadores han cuestionado el estado específico de Dicrodon holmbergi, una especie endémica en situación vulnerable, dado que han encontrado que ninguno de los caracteres diagnósticos que supuestamente la distinguen de D. guttulatum es lo suficientemente ubicuo, y han optado por considerar a D. holmbergi como una subespecie de D. guttulatum. Esta hipótesis taxonómica se sostiene en las marcadas variaciones geográficas a lo largo de la distribución de Dicrodon guttulatum, así como por las grandes similitudes morfológicas y ecológicas entre estos dos taxones; sin embargo, aún no hay un consenso claro sobre la situación taxonómica de D. holmbergi. Con el fin de esclarecer este problema taxonómico, registré 11 caracteres morfométricos, 10 merísticos y 6 categóricos en 227 especímenes de Dicrodon guttulatum y D. holmbergi. Los análisis univariados y multivariados que evalúan diferencias en tendencia central indicaron diferencias significativas en los caracteres morfométricos y merísticos, mientras que los análisis de componentes principales de datos morfométricos, análisis de correspondencia de datos merísticos, y la estimación de intervalos de tolerancia normal de ambos conjuntos de datos mostraron un extenso solapamiento. La morfología hemipeniana tampoco distinguió claramente estos dos taxones. Dado que ninguno de los caracteres diagnósticos usados en la descripción de Dicrodon holmbergi permite reconocerlo inequívocamente de D. guttulatum, propongo que Dicrodon holmbergi sea considerada como una subespecie o variación geográfica de D. guttulatum, hasta que nuevos estudios evalúen esta hipótesis taxonómica. / Tesis

Between February 1986 and October 1988, 863 amphibians and reptiles were collected in northcentral Texas and examined for coccidial parasites. Thirteen percent of amphibians <26% salamanders, 11% frogs and toads) and 28% of reptiles (54% turtles, 25% snakes) harbored 20 previously described and 16 new species of coccidia; overall prevalence of infection was 176/863 < 20%). Sixteen Ambvstoma texanum were infected with Eimeria ambystomae which represents new host and geographic locality records for the coccidium. Forty anurans were found to be passing coccidia, including Pseudacris streckeri. Bufo valliceos and Gastrophryne olivacea. Four new species of coccidia were described from anurans and include Eimeria flexuosa. E. streckeri. Isospora dellcatus and I_. fraaosum. However, oocysts found in B. v.. valliceps were determined experimentally to represent pseudoparasites. Sixty-eight turtles were infected with coccidia, including Chelvdra serpentina, Kinoeternon flavescens. Pseudemvs texana. Terrapeng ornata and Trachemvs scripta eleoans. Fourteen eimerians (5 of which are described as new species) were found in turtles. The new species from turtles include Eimeria cooteri, E. ornata, E. Btvlosa. E. texana and E. trachemvdis. Interestingly, all 96 lizards examined were negative for coccidia. Fifty-three snakes including 11 colubrids and 1 viperld harbored coccidia of the genera Caryospora. Cryptosporidium. Eimeria and Sarcocystis: prevalence of infection was highest in 3 species of North American water snakes <Nerodia spp.). Seven new species of Eimeria were described from snakes, including E. conanti. E. lnfirmus. E. papillosum. E. rhombifera. E. serpenticola. E. striatula and E. tenuis. There was no preference for coccidia between the sexes of any hosts. Based on limited data from a single anuran host, prevalence was higher during wetter months of spring than in summer. In addition, prevalence was higher in aquatic and semiaquatic snakes than in truly terrestrial species. Preliminary data suggested that using host specificity data of coccidia may be a method of studying host phylogeny and coevolutionary relationships in thamnophiine snakes.

Mixosaurid ichthyosaurs (mixosaurs) are a dominant group of Middle Triassic marine reptiles that was widely distributed in both Tethyan and Panthalassic terranes. They are represented by many excellently preserved specimens from all around the world and have been studied for more than one hundred years. Even so, their morphology is not adequately known. The systematics of mixosaurs is not well understood and their phylogeny has been controversial. The nomination of several Chinese mixosaurs makes the situation even worse. This thesis aims to provide a comprehensive review of Chinese mixosaurs and discuss their phylogenetic relationships. The detailed anatomy of only valid Chinese mixosaurid species Mixosaurus panxianensis is well established in this thesis. Its ontogenetic changes are also noted and a better diagnosis is given. A new morphotype of mixosaurs from a recently discovered fossil Lagerst?tte, the Luoping biota, is described in detail. This morphotype is similar to M. panxianensis but consistent differences are also present. The ecological comparison to M. panxianensis demonstrates that this morphotype represents a new taxon that is different from M. panxianensis. A nearly complete and articulated specimen of Phalarodon atavus from the Middle Triassic Luoping biota, Yunnan, South China is described. This is the first specimen of P. atavus discovered outside the Germanic Basin. The discovery of this specimen demonstrates a cosmopolitan distribution of P. atavus across the whole Tethyan ocean. The new specimen is also the first one preserving the postcranial anatomy of this species, providing the potential to evaluate its swimming ability for the first time. Functional morphology shows that this species is well adapted for a pursuit attack of prey, consistent with the distribution pattern of the species. Tooth crown morphology suggests that P. atavus may prefer externally soft prey such as belemnoids. Mixosaurs are divided into three ontogenetic stages based on the humeral morphology. The juvenile stage is characterized by a textured dorsal humeral shaft surface. The subadult stage is characterized by a smooth humeral shaft in dorsal view with a rugose humeral head. The adult stage is characterized by a smooth humeral head. The consistent presence of the surface texture of ventral humeral shaft is most probably caused by the strong muscle insertion presumably related to the function of steering of the fore fins in mixosaurs. Five morphotypes of Chinese mixosaurs are recognized in this study. Twenty-five more or less new characters are introduced to evaluate the phylogenetic relationships of mixosaurian-like specimens from China. The monophyly of mixosaurs including all studied Chinese morphotypes is well corroborated. Further investigation on the mixosaurs from Monte San Giorgio is recommended to resolve the phylogenetic relationships of mixosaurs. / published_or_final_version / Earth Sciences / Doctoral / Doctor of Philosophy

Determining the past, present and future effects of alien species on native biodiversity is a globally recognized problem. The Wall Lizard, Podarcis muralis, was introduced to Vancouver Island from Europe in 1970. To assess potential competitive interactions with the native Northern Alligator Lizard (Elgaria coerulea), I investigated several aspects of P. muralis ecology. D i h i o n along manmade corridors (e.g. roads and powerlines) and human-facilitated jump dispersal are contributing to range expansion; three separate populations currently exist. Reproductive output of P. muralis was not affected by amount eaten while gravid, but feeding level and incubation temperature affected offspring phenotypes. In comparative tests of locomotor performance, P. muralis was faster than Z. coerulea, but only at moderate temperatures. I found no effect of P. muralis dour on E. coeruela behaviour, but E. coeruela avoided cover objects that housed P. muralis. These two species use similar habitats, but were found on different substrates and mesoslopes. Based on the results of these experiments there is a potential for comvetition between these two lizard species.

Orientador: Hussam El Dine Zaher / Banca: Ana Lúcia da Costa Prudente / Banca: Miguel Trefaut Urbano Rodrigues / Banca: Paulo G. Homem Passos / Banca: Otávio Augusto Vuolo Marques / Resumo: A origem e a evolução da função venenosa nas serpentes têm sido objeto de inúmeras discussões. De um modo geral, os estudos se restringem às glândulas de veneno ou de Duvernoy, ambas constituídas por células serosas. Pouca atenção é dispensada às demais glândulas orais e no papel biológico de suas secreções. Nos dipsadíneos goo-eaters, uma linhagem altamente especializada de serpentes comedoras de invertebrados, especialmente moluscos e anelídeos, as glândulas de Duvernoy são reduzidas ou ausentes, enquanto que as glândulas infralabiais são predominantemente seromucosas e associadas à musculatura adjacente. Além disso, uma série de modificações dentárias, particularmente nos dentes maxilares e dentários, são associadas à estas serpentes. Este conjunto de características glandulares, musculares e dentárias são frequentemente relacionados à dieta especializada. O presente trabalho teve o objetivo de realizar um estudo comparativo acerca da anatomia, histologia e histoquímica das principais glândulas cefálicas (infralabiais, supralabiais, Duvernoy e de Harder) e ultraestrutural dos dentes maxilares e dentários dos dipsadíneos gooeaters, utilizando para comparações, serpentes dipsadíneas que comem vertebrados. Além disso, foi realizado um estudo acerca do desenvolvimento embrionário das glândulas labiais (infra e supralabiais) de Sibynomorphus mikanii. Cabeças inteiras de espécies representativas dos diversos gêneros de dipsadíneos goo-eaters, bem como dos gêneros de dipsadíneos que comem vertebrados foram dissecadas e submetidas ao processamento histológico. Embriões de Sibynomorphus mikanii foram estudados através da morfologia externa e séries histológicas das cabeças, enquanto que os dentes maxilares e dentários foram estudados por microscopia eletrônica de... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The origin and evolution of the venomous function in snakes has been subject of recent debates. In a general way, studies on this subject are restricted to the venom and Duvernoy's glands, both constituted by serous cells. Little attention has been given to the others oral glands, such as infralabial and supralabial, and the biological role of their secretions. In the goo-eater dipsadines, a highly specialized lineage of snakes feeding on invertebrates, specially mollusks and annelids, the Duvernoy's glands are very reduced or absent, while the infralabial glands are predominantly constituted by seromucous cells and associated with adjacent muscles. In addition, several dental modifications, particularly in the maxillary and dentary teeth, are associated with these snakes. These muscular, glandular and dental features are frequently associated with highly specialized diet presented by the goo-eaters. This study aimed to perform a comparative study on the anatomy, histology and histochemisty of the major cephalic glands (infralabial, supralabial, Duvernoy and Harder), and the ultrastructure analysis on the maxillary and dentary teeth of the goo-eater dipsadines and the dipsadinae snakes feeding on vertebrates. Furthermore, a study on the embryological development of the labial glands (infralabial and supralabial) in Sibynomorphus mikanii was performed. Whole heads of representative species of several genera of goo-eater and vertebrate feeding dipsadines were dissected and submitted to histological procedures in paraffin. Embryos of Sibynomorphus mikanii in different stages of development were submitted to studies of external morphology and histological sections of the whole heads and the maxillary and dentary teeth were analyzed by scanning microscopy. In Dipsas, Sibynomorphus and Geophis, the... (Complete abstract click electronic access below) / Doutor

Tabelas de estágio embrionário podem ser utilizadas para detectar semelhanças e diferenças de caracteres entre grupos e como ferramenta para estudos baseados na fase embrionária. Neste estudo, ovos do lagarto Iguana iguana foram utilizados para a elaboração de uma tabela de estágios e para determinar o padrão de excreção durante o desenvolvimento. Iguana é um modelo conveniente por produzir numerosas desovas de ovos de tamanho grandes, propiciando um fácil manuseio e um bom número de réplicas. Após a oviposição, 18 estágios embrionários foram determinados durante os quais uréia foi o resíduo nitrogenado principal. Apesar do iguana ser o primeiro lagarto estudado, o padrão ureotélico é comum entre a maioria das espécies reptilianas estudadas até o momento. A casca pergaminácea permite que os ovos dobrem em massa devido à absorção de água, e o mecanismo pelo qual os embriões lidam com a diluição e osmolaridade resultante é um tema interessante para futuros trabalhos e comparações com espécies de cascas rígidas. Há evidência de desenvolvimento heterocrônico dos membros e o desenvolvimento de iguana é similar ao do lagarto Anolis sagrei, também do clado Iguania. Mais estudos de desenvolvimento de lagartos são necessários e a utilização de critérios morfológicos similares para facilitar a comparação de eventos embrionários. / A Table of embryonic stages can be used to detect similarities and differences in developmental features between groups and as a tool for studies based on embryonic phase. In this study, eggs of the lizard Iguana iguana were used to elaborate a staging table and to determine the nitrogen excretion pattern during the development. Iguana is a convenient model for having a large clutch of large eggs, allowing an easy handling and a good number of replicates. After oviposition embryonic stages were determined during which urea was the main nitrogen waste. Although iguana is the first lizard studied, the ureotelic pattern is common among the majority of reptilian species so far studied The pergaminaceous shell allows that the eggs double in mass due to water absorption, and the mechanism and how the egg deals with dilution and resultant osmolarity is an interesting issue for future works and comparisons with species of rigid eggshells. There is evidence of heterocronic development of the limbs and the development of iguana is similar to the lizard Anolis sagrei, also from the clade Iguania. Further studies on lizard evelopment are required and the use of similar morphological approach to facilitate comparisons of embryonic events

Os répteis compõem hoje uma classe com mais de 8.000 espécies e em razão das restrições na importação desses animais, o risco na introdução de doenças exóticas, o crescente número de espécies ameaçadas no mundo, entre outros, a reprodução e a manutenção em cativeiro desses animais é muito importante. No Sul da Califórnia, que é considerado um Hotspot para a biodiversidade, a Zoological Society of San Diego mantém uma reserva ecológica com aproximadamente 400 hectares e formada por vegetação tipo Chaparral, Coastal Sage Scrub e áreas cobertas por cactos (Opuntia sp.). Durante o período de junho de 2005 a julho de 2006 foram capturadas 96 cascavéis das espécies Crotalus ruber ruber, C. oreganus helleri e C. mitchellii phyrrus, durante os trabalhos de campo pela procura visual limitada por tempo. Foram realizadas avaliações morfológicas e reprodutivas em todas essas serpentes capturadas. Nos machos realizou-se a colheita e avaliação de sêmen, incluindo duas colorações específicas para avaliar integridade de membrana espermática e do acrossoma. Nas fêmeas foi realizada a avaliação ultra-sonográfica dos ovários, com mensuração e contagem de folículos, além do diagnóstico de gestação. Para a C. ruber ruber, a serpente mais abundante neste estudo, foram observadas fêmeas prenhes no verão e vitelogênicas na primavera, outono e inverno. Apenas as fêmeas desta espécie com condição corporal boa ou muito boa apresentaram-se vitelogênicas ou prenhes. Nos machos dentre as características seminais avaliadas, não foi observada a diferença estatisticamente significante ao longo das estações do ano. Em paralelo a este estudo, também foram testados protocolos para a congelação de sêmen de serpentes, com a obtenção de resultados promissores, discutidos em capítulo específico. As informações obtidas neste estudo visam contribuir para a compreensão da biologia reprodutiva e conservação das serpentes, em cativeiro ou vida-livre. / There are more than 8,000 reptile species in world. Today´s restrictions to importation of these species around world, the risk of introduction of exotic diseases, the growing number of endangered reptiles, among other reasons, emphasize the importance of reproduction in captivity and ex-situ conservation. South California is a Hotspot for biodiversity and the Zoological Society of San Diego maintains a nature preserve in Escondido City. In an area of about 400 hectares, composed by vegetation types like Chaparral and Coastal Sage Scrub, it has been found the greatest diversity of snake in region. Between May 2005 and July 2006, 96 rattlesnakes of species Crotalus ruber ruber, C. oreganus helleri and C. mitchellii phyrrus were captured by active searching during field work. In the Laboratory of Reproductive Physiology the snakes were measured, weighted, and marked the captured snakes. We evaluated their body condition, collected and evaluated semen from males and performed ultrasound exams in females. Snakes were released up to 24 hours after capture. The Crotalus ruber ruber studied initiated vitellogenesis in fall, courtship and mating occurred in spring and gravid snake were observed in spring and summer. Only females with a good or very good body condition were in secondary vitellogenesis or gravid. There were no statistical differences in seminal parameters among season in males of the Crotalus ruber ruber. Protocols to freeze snake´s semen were tested in this study, with positive results that are discussed in specific chapter. This study results contribute to understand of snake´s biology of reproduction and in or ex-situ conservation.