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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Développement de nouvelles méthodes de préservation du bois basées sur l'utilisation combinée d'un traitement thermique et de borax / Development of new wood treatments combining boron impregnation and thermo-modification

Salman, Solafa 03 March 2017 (has links)
Les pressions environnementales apparues en France et en Europe au cours des dernières décennies ont considérablement changé les méthodes de protection du bois. Dans ce contexte, le règlement relatif aux produits biocides et la directive relative aux produits biocides conduisent au développement de méthodes de préservation plus soucieuses de l'environnement et à l’intérêt croissant pour des alternatives non biocides comme le traitement thermique ou la modification chimique. Le traitement thermique à des températures de 180 à 220°C conduit à la modification chimique de la structure des différents constituants pariétaux du bois en lui conférant de nouvelles propriétés comme une meilleure résistance aux champignons basidiomycètes et une grande stabilité dimensionnelle. Malgré ces améliorations, la durabilité conférée au bois traité thermiquement demeure insuffisante pour des applications en classes 3 ou 4 dans lesquelles le bois est en contact avec le sol ou est en présence de termites. Par ailleurs, le bore sous forme d’acide borique ou de borax présente des propriétés fongicides et termiticides. Cependant, les produits à base de bore présentent l'inconvénient d'être très facilement lessivables les rendant inutilisables pour des applications en conditions extérieures. Les modifications chimiques réalisées suite à l'imprégnation de solutions à 10% d'anhydride maléique de polyglycérol ou de méthacrylates de polyglycérol ou de résine phénol formaldéhyde avec ou sans borax avant le traitement thermique ont apporté une amélioration des propriétés des bois modifiés thermiquement et surtout une résistance aux termites avec ou sans lessivage / Environmental pressures appeared in France and in Europe in the last decades have substantially changed the methods for wood protection. In this context the Biocidal Products Regulations and the Biocidal Products Directive lead to the development of more environmentally friendly preservation methods and the growing interest in non-biocidal alternatives such as thermal treatment or chemical modification. Wood heat treatment at temperatures of 180 to 220 °C leads to the chemical modification of wood cell wall polymers conferring new properties to the material like its increased decay resistance and high dimensional stability. Despite these improvements, the durability of wood heat treatment is not sufficient to envisage use class 3 and 4 applications; where the wood is in contact with soil or termites. Moreover, Boron compounds present fungicidal and termiticidal properties. However, boron compounds have the drawback of being very easily leached out from wood making it unusable for applications in outdoor conditions. Wood chemical modification carried by the impregnation of aqueous solutions (10 %) of maleic anhydride polyglycerol adduct or polyglycerol methacrylates or phenol-formaldehyde resin, with or without borax followed by heat treatment at 220°C has shown some improvement of thermally modified wood properties particularly its resistance to termites in case of leach or not
82

Exploration du microbiote d'invertébrés par métagénomique fonctionnelle et caractérisation structure-fonction d'une nouvelle xylanase / Exploration of the microbiota of invertebrates by functional metagenomics and structure-function characterization of a new xylanase

Guyez, Barbara 06 December 2016 (has links)
La paroi végétale est une structure complexe composée principalement de polysaccharides (cellulose, hémicellulose et pectine), de lignine et de protéines. Elle est impliquée dans de nombreuses fonctions essentielles à la vie de la cellule végétale. De plus, les constituants de cette paroi, que sont les polysaccharides et la lignine, représentent la plus grande source de carbone renouvelable de la planète. Ceci en fait des cibles de choix notamment pour la production d'énergies « vertes ». Toutefois, l'utilisation des polysaccharides tels que les hémicelluloses constituant la paroi végétale reste, à l'heure actuelle, limitée du fait de la difficulté à les dégrader. Ces dernières années, un effort important a été mis en œuvre pour identifier et caractériser de nouvelles enzymes, telles que les glycosides hydrolases, permettant de dégrader efficacement la biomasse végétale. Dans le but de découvrir de nouvelles enzymes impliquées dans la dégradation de la biomasse végétale, des chercheurs de l'équipe « Catalyse et Ingénierie Moléculaire Enzymatiques » du LISBP ont décidé d'explorer le métagénome d'organismes connus pour dégrader la biomasse végétale. Deux espèces animales ont fait l'objet d'analyses : tout d'abord les termites qui sont considérés comme les champions de la dégradation de la biomasse végétales et souvent comparés à des bioréacteurs, et le ver de terre. Des banques métagénomiques de trois espèces différentes de termites ainsi qu'une banque métagénomique de ver de terre ont ainsi été créées. Dans ces travaux de thèse deux des banques métagénomiques de termites, celle de Nasutitermes corniger et celle de Termes hispaniolae, ont fait l'objet d'une étude afin de comparer le potentiel hémicellulolytique de ces deux espèces. Après sélection de nombreux clones positifs sur substrats chromogéniques de chacune des deux banques, séquençage puis annotation taxonomique et fonctionnelle, un grand nombre d'enzymes et principalement des glycosides hydrolases, a pu être identifié. Les résultats montrent que le métagénome de Nasutitermes corniger présente majoritairement des enzymes à activité endoglycosidase alors que le métagenome de Termes hispaniolae possède plutôt des enzymes à activité exoglycosidase. Toutes les activités trouvées dans chacune des espèces de termite sont en bonne corrélation avec l'alimentation du termite. De plus, nous avons observé que le microbiote intestinal des deux termites ne possèdent pas les mêmes embranchements bactériens majoritaires et nous avons pu voir que le microbiote de Termes hispaniolae est plus diversifié ce qui corrèle aussi avec l'alimentation des deux termites. D'autre part, dans la banque métagénomique du ver de terre, l'annotation fonctionnelle a révélé une enzyme intéressante. Il s'agit d'une enzyme annotée par B. Henrissat (responsable de la base de données CAZy) comme étant une glycoside hydrolase putative mais n'appartenant à aucune des 135 familles de glycosides hydrolases existantes. Cette enzyme putative, appelée GH* présente des similitudes avec les GH de la famille 5 sans pour autant appartenir à cette famille du fait notamment de l'absence du résidu catalytique nucléophile conservé. Une étude structurale et fonctionnelle de GH* a donc été menée. Les expériences ont permis de prouver que GH* est une endo-xylanase ayant une préférence pour les arabinoxylanes et les xylooligosaccharides de degré de polymérisation d'au moins 5 ou 6. La structure tridimensionnelle de GH* à 1,6Å de résolution a été obtenue par cristallographie des rayons X par remplacement moléculaire à l'aide d'une GH5. Cette structure a permis de confirmer l'identité du résidu acide/base identifié par alignement de séquences et d'émettre une hypothèse sur l'identité du résidu nucléophile. Enfin des mutants de GH* pour ces deux résidus ont été obtenus et ont confirmé leur implication dans l'activité de l'enzyme. / Plant cell wall is a complex structure surrounding plant cells mainly composed by polysaccharides (cellulose, hemicellulose and pectin), lignin and proteins. The plant wall maintains and imposes the size and shape of cells. It is also important for exchanges between cells and extra cellular medium. The polysaccharides of this cell wall are the largest renewable carbon source on the earth, which makes them good targets to produce green energies. Because plant cell wall is difficult to degrade, its use for biofuels for is still limited. However, some organisms are able to efficiently degrade this biomass. Exploring the diversity of the living word to discover new effective biocatalysts has grown considerably last years, because of the emergence of metagenomics. In this context and to discover new enzymes involved in the degradation of plant biomass, the team « Catalyse et Ingénierie Moléculaire Enzymatiques » of LISBP decided to explore metagenome of organisms known to degrade plant biomass. Two animal families were chosen for metagenomics analysis, the termite and earthworm. Metagenomics banks of three different species of termite and one metagenomics bank of an earthworm were created. In this thesis project, two of the three metagenomics banks of termites, the one from Nasutitermes corniger and the other one from Termes hispaniolae, were studied to compare the hemicellulolytic potential of these two species. After selection of many positive clones on chromogenic substrates of both banks, sequencing, taxonomic and functional annotations, a large number of enzymes and mainly glycoside hydrolases, could be identified. The results obtained shown that the trends observed during functional screens were maintained. Indeed, it appears that Nasutitermes corniger has a majority of endoglycosidases while Termes hispaniolae has mainly exoglycosidases. Thereby, families of enzymes highlighted allowed correlating their hydrolytic activities with the diet of these species. Furthermore, we observed that the intestinal microbiota of each termite is different. Indeed, both termites do not have the same majority bacterial phyla and the microbiota of Termes hispaniolae is more diverse than the one of Nasutitermes corniger. On the other hand, functional annotation of the metagenomics bank of the earthworm revealed an enzyme annotated as a glycoside hydrolase no belonging to any of the 135 glycoside hydrolase existing families. This enzyme, named GH*, seems to be close to GH5 but does not shown the nucleophilic catalyst residue perfectly conserved in this glycoside hydrolase family. A functional and structural study of GH* was then done. We have shown that GH* is an endo-xylanase which prefers arabinoxylans and xylooligosaccharides having a polymerization degree greater than 5. In addition, we determined the crystal structure of GH* at 1.6Å resolution. This 3D structure has confirmed the presence of the acid/base residue identified by sequence alignment and allowed us to hypothesize about the identity of the nucleophilic residue. Finally, mutants of GH* for these two residues were obtained and confirmed their involvement in the activity of the enzyme. We were able to progress in the understanding of structure/function relationships of this protein.
83

Nový případ smíšené reprodukční strategie a její adaptivní význam u neotropického termita Silvestritermes minutus (Termitidae: Syntermitinae) / New case of mixed reproductive strategy and its adaptive significance in the neotropical termite Silvestritermes minutus (Termitidae: Syntermitinae)

Křivánek, Jan January 2016 (has links)
Thanks to the progress in genetic methods in population ecology, many critical discoveries were recently made in the field of reproductive strategies of social insect. Among them is the description of mixed reproductive strategies, combining advantages of sexual reproduction with thelytokous parthenogenesis. The queens of such species produce sterile castes through classical sexual process from fertilized eggs, while future queens develop asexually from unfertilized eggs. This original breeding system was first described in several genera of ants, but it was found very recently, that it is not restricted to social Hymenoptera, since it has been identified also in the phylogenetically remote eusocial clade of termites. Switching between the sexual process and thelytokous parthenogenesis, now known as Asexual Queen Succession (AQS), which enables a continuity of genetically almost identical queen generations after the death of the founding primary queen, was first reported only in one genus of lower termites, i.e. Reticulitermes. Recently, our research group participated at the identification of AQS in four other species from two subfamilies in higher termites. One of these species is Silvestritermes minutus. This species is locally abundant in French Guiana and lives in small, well shaped nests on...
84

Ecological relationships between the armadillo lizard, Cordylus cataphractus, and the southern harvester termite, Microhodotermes viator

Shuttleworth, Cindy 12 1900 (has links)
Thesis (MSc (Botany and Zoology))--University of Stellenbosch, 2006. / The role of the southern harvester termite, Microhodotermes viator, and several climatic parameters in the distribution of the group-living lizard, Cordylus cataphractus, was investigated. Microhodotermes viator is considered the most important prey item of C. cataphractus and termitophagy as the causative agent in the evolution of group-living in this species. One would therefore expect a high degree of correspondence in the ranges of C. cataphractus and M. viator. As climate will also play a role in the distribution of any species, various climatic variables were investigated to determine their influence on the distribution of C. cataphractus. Species distributions were visualized using the minimum polygon technique and the degree of overlap was determined using standard geographic information systems (GIS) techniques. A total of 53 C. cataphractus localities were investigated for the presence of termites. The climatic limits of the geographical distribution of C. cataphractus were investigated by means of three models, namely Classification Trees, General Discriminant Analysis and Logistic Regression. The range of C. cataphractus was completely included within the range of M. viator Microhodotermes viator was included in the diet of C. cataphractus at 73 % of the localities sampled within the lizard’s range. The current geographical range of C. cataphractus is mainly correlated with two climatic factors, namely the low summer rainfall and high monthly solar radiation. The restricting role of both these factors can be directly linked to the group-living nature of C. cataphractus. If termitophagy were the overarching cause of group-living in C. cataphractus, then one would expect a close relationship between termite density and lizard density and termite density and lizard group size. I investigated these relationships at both a local and regional scale. For the local scale study, 25 quadrats of 25 × 25 m were plotted at a selected site, and for the regional scale study, ten 35 × 35 m quadrats at sites throughout the lizard’s range were used. In each quadrat, a range of variables were recorded, the most important of which were lizard density, lizard group sizes, termite foraging port density, distance to nearest termite foraging ports, vegetation height and vegetation cover. I found that the density of termite foraging ports determines C. cataphractus density. Vegetation height and cover affects crevice selection by C. cataphractus groups, probably because an unobstructed view is necessary to locate termite activity at foraging ports. I also investigated possible differences in the use of termites by different sized groups of C. cataphractus during different times of the year. Faecal samples, collected once a month at Eland’s Bay from small, medium and large groups from January 2005 to December 2005, were analysed for the presence of termite head material. I found that large groups fed on termites to a greater extent than small groups during certain times of the year and there was a general tendency for this phenomenon throughout the year. The results collected in this study indicate that the southern harvester termite, M. viator, plays a central role in the ecology of the group-living lizard, C. cataphractus.
85

The Anoplotermes group in French Guiana :systematics, diversity and ecology

Bourguignon, Thomas 28 May 2010 (has links)
Les termites forment un groupe animal important en milieu tropical, où leur richesse spécifique est plus élevée que dans n’importe quel autre écosystème. Ils se nourrissent de matière organique végétale à différent état de décomposition, du bois dur à la matière organique minérale du le sol. Cette diversification du régime alimentaire ne se produit que chez les Termitidae, parfois appelés « termites supérieurs », alors que les autres familles se nourrissent exclusivement de bois ou d’herbe. Les termites humivores sont extrêmement abondants en Amérique du Sud et en Afrique tropicale, mais sont relativement peu étudiés par rapport aux termites xylophages. C’est particulièrement vrai pour le groupe Anoplotermes, qui représente le groupe de termites le moins bien connu. Ce travail vise à faire la lumière sur l’écologie et la diversité de ce groupe strictement humivore, et comprend les sections suivantes :(1) Des échantillonnages standardisés dans sept sites de Guyane Française ont révèle, avec quelques exceptions, que les termites xylophages sont relativement peu spécialisés à un site. Au contraire, les espèces du groupe Anoplotermes, ainsi que les termites humivores en général, sont spécialisés à un type de forêt. Cette spécialisation contribue plus que probablement à la diversification écologique, et donc, à une augmentation de la richesse spécifique des termites humivores. (2) En utilisant les ratios d’isotopiques δ13C et δ15N, nous avons aussi trouvé qu’il existe une spécialisation des espèces le long d’un gradient d’humification chez le groupe Anoplotermes, de l’interface entre le bois pourri et le sol au sol pauvre en matière organique. Donc, au moins deux facteurs favorisent la richesse spécifique du groupe Anoplotermes dans le sol, malgré le manque d’évidence pour une séparation spatiale et temporelle entre les espèces. Cette spécialisation spécifique réduit la compétition interspécifique aux espèces se nourrissant de matière organique au même état de décomposition. (3) Ce mécanisme n’est probablement pas restreint aux espèces du groupe Anoplotermes et le ratio isotopique δ15N varie considérablement entre les termites humivores de manière générale. Les termites humivores comptent des espèces avec des régimes alimentaires différents ne partageant pas toujours les mêmes niches écologiques. Cette diversification du régime alimentaire ne c’est pas produit de manière aléatoire durant l’évolution des termites et les espèces proches tendent à se nourrir du même substrat. (4) Au niveau intraspécifique, il semble que la compétition contraigne la dynamique des colonies. En effet, chez A. banksi, nous avons trouvé que les nids matures sont surdispersés. Les nouveaux nids se trouvent principalement à une certaine distance des nids établis, plus particulièrement dans les trous laissés par les nids morts. Si ce patron est le résultat d’une sélection des sites de nidification, ou plutôt d’une exclusion compétitive reste sujet à discussion, mais met néanmoins en évidence la présence de compétition chez les termites humivores du groupe Anoplotermes. (5) Au vu de la richesse spécifique locale du groupe Anoplotermes, le nombre d’espèces décrites reste remarquablement bas. Après inspection du matériel type, seuls 30 espèces du groupe se sont avérés valides en Amérique du Sud, alors que 80% des espèces que nous avons collectées sont nouvelles pour la science. Cette disproportion entre ce qui est connu et la diversité réelle du groupe, met en évidence le besoin de réaliser des études supplémentaires pour améliorer la connaissance de ce groupe peu connu, le groupe Anoplotermes. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished
86

NEW INSIGHTS INTO THE FUNCTION AND DEVELOPMENT OF THE SOLDIER CASTE IN TERMITES

Tian, Li 01 January 2015 (has links)
The evolution of nonreproductive castes is a defining characteristic of eusociality. The function and developmental regulation of the altruistic worker and soldier caste is the central element contributing to major advantages of eusociality over solitary animals. The soldier caste is the first evolved sterile caste in termites. Their primary function is believed to be colony defense. However, the function and development of termite soldiers remains largely unknown. Because of their apparent morphological adaptation for fighting and their limited behavior repertoire, our understanding of colony defense by termite soldiers is limited to their physical defense. In addition, we know little about the molecular mechanisms mediating soldier development. In Chapters 2 and 3 I discuss the role of the soldier caste under competition risk. By exposing the Eastern subterranean termite Reticulitermes flavipes to cues of a competitor termite species, I found that exposure to competitor cues reduced feeding, compromised growth and survival of R. flavipes workers. The presence of R. flavipes soldiers largely ameliorated these negative impacts. At the transcriptional level, R. flavipes soldiers can counteract the effects of competitor cues on worker head gene expression. This counteracting effect seems to be associated with genes in metabolism and immunity. These studies demonstrate that competition can affect a termite colony’s fitness by either competitors physically invading the colony and causing damage or cues from competitors inducing a stress response in termite colony members. More importantly, soldiers can contribute to colony fitness by physically engaging in combat, but also by enhancing colony members’ survival under competitor-cue exposure. In Chapter 4, I describe the molecular mechanism mediating soldier-caste differentiation. I cloned the full length cDNA sequence of the R. flavipes Methoprene-tolerance (Met) gene, a gene encoding a putative receptor for juvenile hormones. Using RNA interference, I studied the function of Met and found that this gene essentially mediates the JH-dependent soldier-caste differentiation in termites.
87

Factors affecting possible management strategies for the Namib feral horses / Telané Greyling

Greyling, Telané January 2005 (has links)
Demographic, biological and behavioural knowledge, together with information on the ecological interactions and impact of a species is fundamental to effective management of most mammal species. In this study, these aspects were investigated for a population of feral horses in the Namib Naukluft Park of Namibia, which lies within a part of the Namib Desert. An attempt was made to evaluate the justification of the continued existence of this exotic species in a conservation area, as well as to provide baseline information and recommendations regarding management of these horses. The study investigated the botanical component and grazing capacity of the area inhabited by the horses, as well as the demography and quality of life of the horses. The study further examined the possible negative impact the horses may have on the natural biodiversity of the area. Finally, it looked at the historic, scientific, aesthetic and economic values of the horses. The collected data was then used as a technical basis for the development of a draft management plan during a stakeholder workshop. The study proposed a range of grazing capacity values related to the total rainfall of the preceding twelve months, based on grass production in response to rainfall in different plant communities. The horses, as well as the native large herbivores, utilized the study area according to the patchy rainfall patterns typically found in the Namib Desert. The population size of the horses fluctuated between 89 and 149 over a ten year period. The social structure of the population was more significantly influenced by artificial interference than natural disasters which had implications on natality, mortality and genetic viability. Termite activity, measured as utilization of grass provided in bait boxes, did not correlate with horse density and seems, instead, to be influenced by soil properties. The results of ant and tenebrionid beetle species composition surveys and analyses did not indicate a significant negative impact from the horses on the study area. No indication could be found that the horses threaten the survival of any native species in the area or that they change the vegetation structure. It appears as if the biodiversity of the area is subjected to large natural stresses due to the continued and frequent desiccation in the desert environment. The impact of the horses is therefore probably minor to that of the climatic stochasticity. It also became apparent that the horses have developed significant historical, scientific and tourism value. The general public opinion is that the horses should be managed as a wild population with minimal artificial interference. / Thesis (Ph.D. (Zoology))--North-West University, Potchefstroom Campus, 2006.
88

Inter-continental patterns in the fine-scale spatial ecology of rain forest termites

Scholtz, Olivia Ingrid January 2010 (has links)
In this thesis I describe fine-scale spatial patterns in rain forest termites, from the colony to the assemblage level, sampled from one hectare plots in Central African and South East Asian lowland rain forest. By so doing the ecological interactions that structure this functionally important and abundant soil community were identified. The African termite assemblage, dominated by soil-feeding termites, saturated the upper soil profile (collected from 90% of soil pits). In contrast termites were collected from <50% of soil pits in Asia, with this difference reflecting the lower species densities and abundances of soil-feeding termites in Asian forests. Territoriality and inter-specific competition was shown to be important between colonies of soil-feeding species in the African plot. The termite assemblages were spatially associated with several environmental properties. However these could not explain the spatial patterns in the functional components of the assemblages. Wood-feeding termites were highly patchily distributed, due to the heterogeneous nature of their food material, but also due to possible competitive interactions for this. Humus-feeding termites were homogenously structured, due to the continuous nature of soil as their feeding and nesting material. True soil-feeding termites, unique to the African assemblage, were heterogeneously distributed despite the equally continuous nature of their feeding and nesting material. This structure may arise from facilitative interactions, such as co-operative defence against ant predation which may be intense in African systems, or through the transfer of soil material at different stages of decomposition. Competition for space is apparent in both regions, both at the colony level among soil-feeding genera, and between aggregations of functional groups. Positive and negative biotic interactions, operating at various spatial and functional scales, appear to be important in influencing how assemblage composition is spatially structured. If indeed facilitation is important in maintaining the taxonomic and functional diversity in termite assemblages, it would be valuable to confirm the mechanism(s) that drives this (i.e. predation and/or food transfer), as these may then influence ecosystem stability.
89

Specifické chování vojáků vůči pohlavním jedincům termitů rodu Prorhinotermes (Isoptera: Rhinotermitidae). / Specific behaviour of soldiers towards reproductives of termite genus Prorhinotermes (Isoptera: Rhinotermitidae).

Dolejšová, Klára January 2012 (has links)
Soldier caste is the oldest altruistic caste in termites, highly specialized for defensive tasks. Therefore, a number of adaptations in anatomy and behaviour can be observed in soldier, lacking in other termite castes. The aim of this study was to verify the hypothesis that in disturbed groups the soldiers will prefer to stand by and defend the reproductives, the most valuable individuals. Therefore, I studied in two species of the genus Prorhinotermes (P. simplex and P. canalifrons) the ability of soldiers to discriminate neotenic reproductives and provide them with defence. In agreement with the initial hypothesis, the soldiers of both species prooved to be able of an instantaneous recognition of reproductives and remained close to them. In P. simplex, the neotenic female was the most attractive individual, while in P. canalifrons, neotenics of both sexes were equally attractive. The observed preference of reproductives appears to occur only with a certain age of the reproductives in incipient colonies, along with their sexual maturation. Caste specificity of cuticular lipids supports the presumption that the caste recognition is based on olphactoric cues in the cuticle of reproductives.
90

Estudo taxonômico dos Apicotermitinae da Mata Atlântica / Taxonomic study of Atlantic Forest Apicotermitinae

Constantini, Joice Paulo 11 October 2018 (has links)
Apesar de sua relevância ecológica, os Apicotermitinae neotropicais foram taxonomicamente pouco estudados, e nenhum trabalho abrangente de morfologia comparada foi feito sobre eles. Portanto, há uma lacuna na compreensão da variação apresentada por alguns caracteres (especialmente do tubo digestório) em todo o grupo. A morfologia interna e externa de 600 amostras de Apicotermitinae da Mata Atlântica depositadas no MZUSP, juntamente com os tipos do American Museum of Natural History (Nova Iorque) e do Smithsonian Institution National Museum (Washington, DC), foi estudada. O tubo digestório, incluindo a válvula entérica, foi analisado para cada espécie tratada aqui. Foram identificadas 35 espécies, sendo 20 delas ainda não descritas, e outras 15 espécies já conhecidas, cujas áreas de distribuição foram ampliadas. O estudo do material tipo possibilitou a melhoria das descrições de espécies, cujos diagnósticos eram problemáticos. As descrições e redescrições de todas as espécies foram incluídas, bem como ilustrações das principais características, estudo morfométrico e mapas de amostragem. Também foram incluídos comentários sobre o status do material tipo, um breve estudo comparativo de todas as espécies neotropicais e uma chave de identificação baseada nos operários para essas espécies. O estudo comparado deu suporte para novas hipóteses de agrupamento das espécies no nível de gênero, e permitiu avaliar caracteres informativos que têm sido negligenciados em artigos publicados recentemente, como: diferenças nas mandíbulas de operários e alados da mesma espécie, especialmente na região molar, dimorfismo sexual nos alados, presença de órgãos deiscentes no tórax e nos primeiros segmentos abdominais do operário. Conclui-se que é fundamental o estudo da morfologia externa e interna do operário e morfologia externa do alado de forma combinada para um bom diagnóstico em nível específico e genérico, não considerando apenas uma característica (como a válvula entérica) para a separação de táxons. As descrições desses novos táxons permitirão estudos faunísticos comparáveis, levando a um melhor entendimento desse grupo nos ecossistemas neotropicais. / Despite their ecological relevance, the Neotropical soldierless termites were not taxonomically studied enough, and no comprehensive comparative morphology study has been done. Therefore, there is a gap in the understanding of the character variation (mainly those of the gut) in the whole group. External and internal morphology of 600 samples of Apicotermitinae from the Atlantic Forest housed in the MZUSP were studied, along with the types from the American Museum of Natural History (New York) and the Smithsonian Institution National Museum (Washington, DC). The digestive tube, including the enteric valve, of each species herein treated were studied. Thirty five species were identified in total, out of which 20 are undescribed, and the other 15 already described have had an extension of their known distribution. The study of the type material have improved the descriptions of species, whose diagnosis were problematic. Descriptions and re-descriptions of all species were provided, as well as illustrations of the main characteristics, morphometric study and sampling maps. There were also comments on the status of the type material, and a brief comparative study of all Neotropical species plus an identification key for these, based on workers. The comparative study supports the new hypotheses of grouping species at the genus level, and allowed an evaluation of the informative characters often neglected in recent published articles, such as: differences in the mandibles of workers and imagoes of the same species, mainly in the molar region; alate sexual dimorphism; presence of dehiscent organs in the thorax and first abdominal segments in workers. In conclusion, a combined study of both the external and internal morphology of the worker and the external morphology of the alate is fundamental to diagnose both the specific and generic level well, not just taking into consideration one characteristic (such as the enteric valve) to split taxons. Descriptions of the new taxa will enable comparisons among faunistic studies already published, leading to a better understanding of this group in Neotropical ecosystems.

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