Batrachochytrium dendrobatidis (Bd) is a fungal pathogen causing amphibian population declines. Bd has a narrow thermal tolerance and requires moisture to survive. Differences in frog biology, pathogen biology or temperature and moisture conditions may determine population response to disease. Population responses to Bd vary among sites, habitats, species and populations. In the tropics, stream-dwelling species decline to a greater degree than forest species, yet not all stream species decline to extirpation and not all forest species survive. I hypothesized that variation in operative temperature (Te) or body temperature (Tb) might explain differences in host population change documented among sites, seasons, habitats, and species. I sampled three moist-forest Panamanian sites (elevation 375 - 1300 m) during 2.5 months of the 2008 wet season and four different moist-forest sites (elevation 400 - 1300 m) during 3 weeks of the 2008 dry season. I measured Te and Tb of anurans along stream and forest transects. Additional environmental variables such as height, substrate, canopy cover and sunfleck presence were measured concomitantly. I used analysis of covariance to determine whether these factors influenced Te and Tb. I compared frequency distributions of Tb and Te to a Bd thermal growth curve to determine: 1) whether temperatures above Bd's critical thermal maximum were available to frogs, and 2) whether populations of species that have declined occupied habitats more frequently in Bd's optimal thermal range than species that have not. Te and Tb differed among sites, with cooler temperatures at higher elevation. Te was cooler during the dry season yet the presence of sunflecks and open canopy had greater effect on Te during the dry season. Within a site, Te and Tb were not different between habitats. Within a site, Tb did not vary among species. Average Te and Tb for all sites fell within Bd's thermal tolerance range, but the low elevation sites had Tb ranges extending above Bd's critical thermal maximum. Although temperature may explain greater losses at higher elevations, I found no significant difference in operative temperatures between stream and forest habitats at any site which indicates that temperature alone does not explain greater losses of stream anurans. Species that have declined to extirpation elsewhere did not consistently have cooler body temperatures compared to surviving species. Within the Neotropics, moisture, instead of temperature, may explain patterns of Bd prevalence among seasons, habitats, and species.

The Archiborborinae comprise a diverse clade of flies in the family Sphaeroceridae. This thesis presents the first phylogenetic analysis and a thorough taxonomic revision of the subfamily. The phylogenetic revision includes morphological data from all species, and molecular data from a subset of 21 ingroup species. Although the group here treated as the Archiborborinae has been traditionally treated as a tribe within the subfamily Copromyzinae, analysis of morphological, molecular, and combined datasets supports the monophyly of the Archiborborinae and shows that the Archiborborinae and Copromyzinae are not sister taxa. The Copromyzinae are more closely related to the Sphaerocerinae and possibly to the enigmatic genus Pycnopota than they are to the Archiborborinae. The elevation of the clade to subfamily rank is supported on the basis of this evidence. Basal relationships within the Archiborborinae are difficult to resolve, but the phylogenetic evidence generally supports a division of the subfamily into the following 8 genera: Antrops Enderlein 1909, Penola Richards 1941, Frutillaria Richards 1961, Boreantrops gen. nov., Coloantrops gen. nov., Maculantrops gen. nov., Photantrops gen. nov., and Poecilantrops gen. nov. The genus Archiborborus, until recently a paraphyletic assemblage including most of the described species in the subfamily, is treated as a junior synonym of Antrops (syn. nov.) All genera are described and a generic key is provided. A total of 122 species, including 25 previously described and 89 new, are fully described and illustrated; another 8 new species are diagnosed but not formally named.

As espécies neotropicais de Myrtaceae pertencem à tribo Myrteae e a região neotropical concentra a maior diversidade da tribo. Enquanto os estudos sistemáticos do grupo têm avançado, os estudos biogeográficos na região ainda são escassos. Dentre os sete grupos de Myrteae, encontra-se \"Myrcia group\" (=Myrcia s.l.), de distribuição exclusivamente neotropical. O grupo conta com mais de 700 espécies nos três gêneros reconhecidos - Calyptranthes, Marlierea e Myrcia, porém, a sinonimização dos dois primeiros em Myrcia é necessária. Em estudo filogenético recente, foram definidos nove grupos em Myrcia s.l., um deles o clado 7. Os objetivos deste trabalho foram realizar uma análise filogenética do clado 7, concluir a revisão taxonômica e as atualizações nomenclaturais desse mesmo grupo e estudar os padrões biogeográficos de Myrcia s.l. O estudo filogenético do clado 7 conta com 18 dentre as 22 espécies inferidas, somando 105 amostras; as análises de parcimônia e bayesiana foram baseadas nos marcadores ITS, ndhF, psbA-trnH, trnL e trnQ, e a hipótese filogenética foi contraposta com dados morfológicos. Para a revisão taxonômica e as atualizações nomenclaturais, a coleção de 49 herbários foi analisada e 15 expedições de coleta foram realizadas. Para o estudo biogeográfico de Myrcia s.l., a região Neotropical foi dividida em oito unidades; na análise filogenética de Myrcia s.l., incluindo cinco marcadores de 182 amostras, o fóssil Paleomyrtinaea (56 Ma) foi posicionado no crown node de Myrteae e a diversificação das linhagens foi estimada pelo \"lognormal relaxed clock\"; na análise biogeográfica (\"DEC model\"), os valores de \"dispersal constraints\" foram baseados na distância e nas evidências de ligações florísticas entre as unidades. As análises filogenéticas corroboraram o monofiletismo do clado 7, que foi circunscrito morfologicamente e chamado informalmente de Sympodiomyrcia, nome que faz alusão à ramificação simpodial encontrada nas ramificações vegetativas e, principalmente, nas ramificações basais da inflorescência. As relações internas mostram em geral pouca resolução. Calyptranthes emerge como o grupo-irmão de Sympodiomyrcia e a morfologia corrobora tal relacionamento. Na revisão taxonômica, a caracterização da morfologia de órgãos e estruturas do grupo é fornecida, bem como uma chave de identificação para as espécies. O tratamento taxonômico inclui dados nomenclaturais, morfológicos, geográficos, biológicos e de conservação sobre cada espécie. Até o momento, são reconhecidas 21 espécies em Sympodiomyrcia, seis delas inéditas. Com relação ao estudo biogeográfico de Myrcia s.l., a Mata Atlântica Montana aparece como área ancestral em diversas linhagens. Já a diversificação inicial de Calyptranthes provavelmente se deu do Caribe e, subsequentemente, houve uma expansão para o Sul. O Planalto das Guianas e a Mata Atlântica de Terras Baixas também aparecem como áreas ancestrais de grupos de Myrcia s.l. Os principais eventos de diversificação ocorreram ao longo do Mioceno. Apesar dos resultados, verifica-se que ainda é necessário adensar a amostragem, aumentar o número de marcadores e realizar estudos sobre a morfologia e a biologia de Myrcia s.l., o que será fundamental para melhorar a compreensão da história filogenética e biogeográfica deste grande grupo / The Neotropical species of Myrtaceae belong to the tribe Myrteae, which is most diverse in this region. While the systematics studies of the group have experienced gradual progress, the biogeographic studies are still scanty. \"Myrcia group\" (=Myrcia s.l.), exclusively Neotropical, is one of the seven groups of Myrteae. This group comprises about 700 species in the three recognized genera - Calyptranthes, Marlierea e Myrcia, but the synonymization of the two former in Myrcia is needed. In a recent phylogenetic study, nine groups were proposed in Myrcia s.l., one of them been the clade 7. The aims of this study are to carry out phylogenetic analysis and to conclude the taxonomic revision and nomenclatural updates of the clade 7, and to study the biogeographic patterns of Myrcia s.l. The phylogenetic study of the clade 7 includes 18 of the 22 species inferred for the group, totalizing 105 samples; the parsimony and bayesian analyses were based in the ITS, ndhF, psbA-trnH, trnL and trnQ markers, and the results were compared with the morphology. The collections of 49 herbaria were checked and 15 field expeditions were carried out for the taxonomic revision and nomenclatural updates. In the biogeographic study, the Neotropical region was divided in eight units; in the phylogenetic analysis of Myrcia s.l., which includes five markers and 182 samples, the Paleomyrtinaea fossil (56 Ma) was placed at the crown node of Myrteae and the lineage divergence times were estimated by the lognormal relaxed clock; the DEC model was used for the biogeographic analysis, in which the dispersal constraints were based in the distance and floristic links between the units. The phylogenetic analysis confirm that the clade 7 is monophyletic; the group was morphologically defined and informally named Sympodiomyrcia, which alludes to the sympodial branching found in the vegetative branches and mainly in the basal branching of the inflorescence. The internal relationships show low resolution. Calyptranthes is the sister group of Sympodiomyrcia and the morphology reinforces this relationship. A morphological characterization and an identification key for the species are provided in the taxonomic revision. The taxonomic treatment includes nomenclatural, morphological, geographical, biological and conservational data about each species. Until now, Sympodiomyrcia contains 21 species, which six are undescribed. Concerning the biogeographic study of Myrcia s.l., the Montane Atlantic Forest appears as the ancestral area of several lineages. In contrast, the initial diversification of Calyptranthes probably occurred in the Caribbean region and then the group expanded to the south. The Guiana Shield and the Lowland Atlantic Forest also appear as the ancestral area of Myrcia s.l. lineages. The main diversification events occurred during the Miocene. It is still necessary to expand the sampling, to increase the number of markers and to carry out morphological and biological studies of Myrcia s.l., what will be essential to improve the knowledge of the phylogenetic and biogeographic histories of this big group

Tropical habitats have high taxonomic and ecological diversity, but they are currently subject to high rates of extinction. Amphibian populations are declining globally and while we have some understanding of the causes of these declines, it is unclear how these losses will influence ecosystem structure and function. Secondary production and trophic basis of production analyses link consumers to energy flow and reflect the relative importance of various energy sources and energy flow pathways in food webs. These techniques can yield valuable information on the roles of individual consumers in ecosystem function, and thus the ecological consequences of extinction and extirpation events. I estimated the trophic basis of production in a Panamanian headwater stream to identify major sources of energy, measure energy flow through consumers, and characterize interactions among trophic levels and functional feeding groups. I examined gut contents of 19 dominant macroinvertebrate and two dominant tadpole taxa collected during dry and wet seasons before an amphibian decline. I used previously published estimates of secondary production, assimilation efficiencies, and net production efficiencies, along with gut content data, to quantify food web structure and energy flow pathways. Overall consumption of allochthonous materials was greater than autochthonous (p < 0.001), and the dominant food sources were non-algal biofilm and vascular plant detritus. Autochthonous materials were consumed at higher rates during the dry season (p = 0.012). Total consumption rates varied within and among shredders (0.85 - 12.10 g/m2/yr), scrapers (0.46 - 0.91 g/m2/yr), filterers (1.20 - 4.67 g/m2/yr), gatherers (0.43 - 2.44 g/m2/yr) and predators (0.05 - 0.95 g/m2/yr). Overall consumption rates in pool habitats were higher compared to riffles. The degree of omnivory in the food web was much higher than has been observed in similar temperate streams. Omnivory was prevalent across all functional feeding groups, but more pronounced in predators, especially Anacroneuria (55% animal and 45% plant materials in guts). There was also an ontogenetic shift among most dominant macroinvertebrates from smaller, energy rich food sources (e.g., non-algal biofilm) to larger, less nutritious materials (e.g., vascular plant material) with increase in size. My research is the first to provide quantitative estimates of energy flow through a neotropical headwater stream food web. Information from this study is central to understanding and conserving tropical headwater streams. Further, my results, along with post-amphibian decline analyses from the same stream, will allow for a comprehensive assessment of the ecological consequences of amphibian declines.

Closely related species at the same trophic level are often considered to be ecologically equivalent. However, it is clear that individuals species can have unique functional roles that drive community and ecosystem processes. In this study we examine the growth responses of two Neotropical hylid tadpole species, Agalychnis callidryas and Dendropsophus ebraccatus, to intraspecific and interspecific competition. We also look at density-dependent effects of each on phytoplankton, periphyton and zooplankton, as well as their responses to a caged dragonfly predator through ontogeny. Intraspecific competition affected both species similarly, and their effects on resources were qualitatively similar but quantitatively different. Predators affected resource levels and interspecific competition. Predator effects on tadpole size varied in both magnitude and direction through ontogeny for both species. This study shows that closely related species at the same trophic level can have different ecological roles and that tadpoles are more functionally unique than previously thought.

Bignonia, o quinto maior gênero da tribo Bignonieae (Bignoniaceae), é caracterizado por apresentar ramos com cunhas de floema em múltiplo de quatro, folhas 2-folioladas, gavinhas geralmente simples, flores com corola achatada e sem disco nectarífero, e sementes com alas opacas. A atual circunscrição é baseada num recente estudo filogenético que congregou 28 espécies anteriormente posicionadas em oito diferentes gêneros. Esta união tornou Bignonia um grupo complexo, com ampla variação morfológica, criando um grande desafio taxonômico. Assim, os objetivos foram revisar a taxonomia do gênero e reconstruir sua filogenia baseada em caracteres moleculares, incluindo sequenciamento em larga escala, para melhor compreender o grupo. Com o tratamento taxonômico apresentado aqui, são reconhecidas 30 espécies, duas das quais descritas como novas, uma reestabelecida e outra sinonimizada. Foram encontrados dez clados, todos suportados por sinapomorfias morfológicas, que são a base da classificação subgenérica proposta. Os resultados gerados aqui fornecerão subsídios para um futuro estudo evolutivo e biogeográfico / Bignonia, the fifth largest genus in the tribe Bignonieae (Bignoniaceae), is characterized by stems with phloem wedges in multiple of four, leaves 2-foliolated, tendrils usually simple, flowers with dorso-ventrally flattened corolla and absent nectariferous disk, and seed with opaque wings. The current circumscription is based on a recent phylogenetic study that congregated 28 species previously placed in eight different genera. This unification made Bignonia a complex group, with a wide morphological range, which created a big taxonomic challenge. In this manner, the objectives were to review the taxonomy of the genus and to reconstruct its phylogeny using molecular characters, including high throughput sequencing, to better understand this group. With the taxonomic treatment presented here, 30 species are recognized, two of these described as new, one reestablished and another synonymized. Ten clades were obtained, all supported by morphological characters, are the base for the subgeneric classification proposed. The results presented here will provide the base for future evolutionary and biogeographic study

This thesis aims to explore distributional patterns of tree species in the neotropical lowland rain forest biome based on diversity analyses, dated phylogenies and species distribution models, using the family Sapotaceae as a case study. Sapotaceae is an abundant and diverse group in the neotropical lowland rain forest and its distributional patterns are representative of other tree clades in this biome. These characteristics make this family a good model to test ecological and biogeographic hypothesis in neotropical rain forests. An analysis of beta-diversity measured by the number of shared species was used as a test of biotic homogeneity of Morrone's (2001) widely used system of neotropical biogeographic units. Biotic homogeneity was generally low, and Morrone's (2001) biogeographic regionalisation was found not to coincide with the distributional patterns of Sapotaceae species. Divergence times of Sapotaceae species were estimated using a dated phylogeny based on DNA sequences of the nuclear ribosomal internal transcribed spacer (ITS) to explore the effects of Andean uplift, closure of the Isthmus of Panama and Pleistocene climatic changes on the evolutionary history of lowland rain forests in northern South America. The Andean uplift was found to have affected patterns of distribution by creating new habitats and altering hydrologic systems in northern South America, and in some cases by isolating lineages to the east and west of the Eastern Cordillera of the Andes. The closure of the Panama Isthmus and Pleistocene climatic changes do not seem to have strongly affected patterns of distribution or diversification in Sapotaceae. In general, the lack of congruent dates for many repeated biogeographic splits in the phylogeny (e.g., Amazon-Choco) suggests that idiosyncratic dispersal events have had a substantial effects on Sapotaceae's biogeography. Finally, species distribution models generated for Sapotaceae in the Neotropics were used to identify areas of high predicted species richness in Colombia. The highest diversity of Sapotaceae species was predicted for the inter-Andean valleys and northern Amazon. These results were compared to the current system of Protected Areas in this country, demonstrating that areas of high conservation value based on predicted species richness have a low coverage of Protected Areas. Such gaps highlight the potential need for new systems for the delimitation of basic units for conservation at national levels in Colombia.

Bignonia, o quinto maior gênero da tribo Bignonieae (Bignoniaceae), é caracterizado por apresentar ramos com cunhas de floema em múltiplo de quatro, folhas 2-folioladas, gavinhas geralmente simples, flores com corola achatada e sem disco nectarífero, e sementes com alas opacas. A atual circunscrição é baseada num recente estudo filogenético que congregou 28 espécies anteriormente posicionadas em oito diferentes gêneros. Esta união tornou Bignonia um grupo complexo, com ampla variação morfológica, criando um grande desafio taxonômico. Assim, os objetivos foram revisar a taxonomia do gênero e reconstruir sua filogenia baseada em caracteres moleculares, incluindo sequenciamento em larga escala, para melhor compreender o grupo. Com o tratamento taxonômico apresentado aqui, são reconhecidas 30 espécies, duas das quais descritas como novas, uma reestabelecida e outra sinonimizada. Foram encontrados dez clados, todos suportados por sinapomorfias morfológicas, que são a base da classificação subgenérica proposta. Os resultados gerados aqui fornecerão subsídios para um futuro estudo evolutivo e biogeográfico / Bignonia, the fifth largest genus in the tribe Bignonieae (Bignoniaceae), is characterized by stems with phloem wedges in multiple of four, leaves 2-foliolated, tendrils usually simple, flowers with dorso-ventrally flattened corolla and absent nectariferous disk, and seed with opaque wings. The current circumscription is based on a recent phylogenetic study that congregated 28 species previously placed in eight different genera. This unification made Bignonia a complex group, with a wide morphological range, which created a big taxonomic challenge. In this manner, the objectives were to review the taxonomy of the genus and to reconstruct its phylogeny using molecular characters, including high throughput sequencing, to better understand this group. With the taxonomic treatment presented here, 30 species are recognized, two of these described as new, one reestablished and another synonymized. Ten clades were obtained, all supported by morphological characters, are the base for the subgeneric classification proposed. The results presented here will provide the base for future evolutionary and biogeographic study

O gênero Sphecozone O.P.-Cambridge, 1870 inclui 34 espécies e tem S. rubescens como espécie-tipo. Com exceção do norte-americano S. magnipalpis Millidge 1993, todas as espécies do gênero ocorrem apenas nos Neotrópicos. Miller e Hormiga (2004) propuseram o monofiletismo de Sphecozone, suportado pela perda de paracímbio e crista do radix, e a origem de um átrio, e estabeleceram Tutaibo Chamberlin, 1916 como seu grupo irmão, relacionando-o a Ceratinopsis Emerton, 1882, Dolabritor Millidge, 1991 Intecymbium Miller, 2007 Gonatoraphis Millidge, 1991 e Psilocymbium Millidge, 1991 com base na ausência ou redução de paracímbio, estrutura presente nos palpos dos machos da superfamília Araneoidea. Apesar deste resultado, Miller e Hormiga (2004) e Miller (2007) sugerem que a relação interna e monofilia de Sphecozone é duvidosa, e hipóteses sobre a revalidação de um dos gêneros que foi sinonimizado, como Hypselistoides, Tullgren, 1901 Brattia Simon, 1894, Clitolyna Simon, 1894 e Gymnocymbium Millidge 1991 também são discutidos. Neste contexto, este projeto tem como objetivo testar essas hipóteses. A partir de uma matriz de dados contendo um total de 77 caracteres e 41 táxons terminais (8 do grupo externo, 28 do grupo interno e 5 espécies novas) uma análise através de uma busca heurísticas tradicional resultou em apenas duas árvores mais parcimoniosas com 294 passos (IC=0,30; IR=0,57). As topologias obtidas corroboram as hipóteses de Miller e Hormiga (2004) e Miller (2007), ou seja, Sphecozone, não forma mais um grupo monofilético e possui, agora, apenas duas espécies, S. rubescens, O. Pickard-Cambridge, 1871 e S. nitens Millidge, 1991, suportado pela presença de apófise ventral do címbio, perda do paracímbio e papilas no tégulo, cauda do radix reta, perda do tricobótrio prolateral da tíbia do palpo do macho, forma do epígino fortemente ovalado, e presença do tricobótrio no metatarso IV, tendo como grupo irmão o gênero Tutaibo Chamberlin, 1916. As demais espécies estão distribuídas em outros dois gêneros revalidados: um deles Hypselistoidyes, contendo H. altehabitans (Keyserling, 1886) comb. nov., H. capitatus (Millidge, 1991) comb. nov., H. corniculans (Millidge, 1991) comb. nov., H. cornutus (Millidge, 1991) comb. nov., H. crinitus (Millidge, 1991) comb. nov., H. diversicolor (Keyserling, 1886) comb. nov., H. ignigenus (Keyserling, 1886) comb. nov., H. labiatus (Keyserling, 1886) comb. nov., H. lobatos (Millidge, 1991) comb. nov, H. modestus (Nicolet, 1849) comb. nov., H. modicus (Millidge, 1991) comb. nov., H. nigripes (Millidge, 1991) comb. nov., H. niwinus (Chamberlin, 1916) comb. nov., H. rubicundus (Keyserling, 1886) comb. nov. e uma espécie nova, e outro Clytolina, contendo Clytolina fastibilis (Keyserling, 1886) comb. nov., as espécies C. castânea, (Millidge, 1991) comb. nov., C. novaeteutoniae, (Baert, 1987) comb. nov. e C. spadicaria (Simon, 1894) comb. nov., C. crassa (Millidge, 1991) comb. nov., C. gravis (Millidge, 1991) comb. nov. e C. formosa (Millidge, 1991) comb. nov., C. prativaga (Keyserling, 1886) comb. nov., C. personata (Simon, 1894) comb. nov., C. alticeps (Millidge, 1991) comb. nov., C. rostrata (Millidge, 1991) comb. nov., C. tumidosa (Keyserling, 1886) comb. nov., C. venialis (Keyserling, 1886) comb. nov., C. varia (Millidge, 1991) comb. nov., e duas espécies novas, Clitolyna sp.nov.01 e Clitolyna sp.nov.02. Um gênero novo também será proposto para acomodar as espécies Gen.nov. magnipalpis (Millidge, 1993), Gen.nov. sp.nov.01 e Gen.nov. sp.nov.02 / The genus Sphecozone O. P.-Cambridge, 1870 includes 34 species and has S. rubescens as its type-species. Except for the North American S. magnipalpis Millidge 1993, all species of the genus occur only in the Neotropics. Miller and Hormiga (2004) proposed the monophyly of Sphecozone, supported by the loss of paracymbium and radical ridge, and the origin of an atrium, and established Tutaibo Chamberlin, 1916 as its sister group, relating it to Ceratinopsis Emerton, 1882 Dolabritor Millidge, 1991 Intecymbium Miller, 2007 Gonatoraphis Millidge, 1991 and Psilocymbium Millidge, 1991 based on the absence or reduction of paracymbium, structure present in the palps of males of the superfamily Araneoidea. Despite this result, Miller and Hormiga (2004) and Miller (2007) suggest that the internal relationship and monophyly of Sphecozone is doubtful, and hypotheses about revalidation of one of the genus which was synonymized, as Hypselistoides Tullgren, 1901 Brattia Simon, 1894 , Clitolyna Simon, 1894, Gymnocymbium Millidge 1991 are also discussed. In this context, this project aims to test these hypotesys. From a data matrix containing a total of 77 characters and 41 terminal taxa (8 outgroup, 28 ingroup and 5 new species) an analysis through a traditional heuristic search resulted in only two most parsimonious trees with 294 steps (CI = 0.30, IR = 0.57). The topologies obtained corroborate the hypotheses of Miller and Hormiga (2004) and Miller (2007), that is, Sphecozone no longer forms a monophyletic group and has only two species, S. rubescens O. Pickard-Cambridge, 1871 and S. nitens Millidge, 1991, supported by the presence of ventral cymbal apophysis, loss of paracymbium and papillae in the tegulum, straight tailpeace of the radix, loss of the prolateral trichobotrium of tibia from males palpus, strongly oblong epiginum, and the presence of a metatarsus IV trichobotrium. The other species are distributed in two other revalidated genera: Hypselistoidyes, with H. altehabitans (Keyserling, 1886) comb. nov., H. capitatus (Millidge, 1991) comb. nov., H. corniculans (Millidge, 1991) comb. nov., H. cornutus (Millidge, 1991) comb. Nov., H. crinitus (Millidge, 1991) comb. nov., H. diversicolor (Keyserling, 1886) comb. nov., H. ignigenus (Keyserling, 1886) comb. nov., H. labiatus (Keyserling, 1886) comb. nov., H. lobatus (Millidge, 1991) comb. nov, H. modestus (Nicolet, 1849) comb. nov., H. modicus (Millidge, 1991) comb. nov., H. nigripes (Millidge, 1991) comb. nov., H. niwinus (Chamberlin, 1916) comb. nov., H. rubicundus (Keyserling, 1886) comb. nov. and one new species, and Clitolyna, with C. fastibilis (Keyserling, 1886) comb. nov., C. castanea (Millidge, 1991) comb. nov., C. novaeteutoniae (Baert, 1987) comb. nov. and C. spadicaria (Simon, 1894) comb. Nov., C. crassa (Millidge, 1991) comb. nov., C. gravis (Millidge, 1991) comb. nov. and C. formosa (Millidge, 1991) comb. nov., C. prativaga (Keyserling, 1886) comb. nov., C. personata (Simon, 1894) comb. nov., C. alticeps (Millidge, 1991) comb. nov., C. rostrata (Millidge, 1991) comb. nov., C. tumidosa (Keyserling, 1886) comb. nov., C. venialis (Keyserling, 1886) comb. nov., C. varia (Millidge, 1991) comb. nov., and two new species. A new genus will also be proposed to accommodate Gen.nov magnipalpis (Millidge, 1993), Gen. nov. sp.nov.01 and Gen.nov. sp.nov.02

The Myristicaceae, or nutmeg family, consists of 21 genera and about 500 species of dioecious canopy to sub canopy trees that are distributed worldwide in tropical rainforests. The Myristicaceae are of considerable ecological and ethnobotanical significance as they are important food for many animals and are harvested by humans for timber, spices, dart/arrow poison, medicine, and a hallucinogenic snuff employed in medico-religious ceremonies. Despite the importance of the Myristicaceae throughout the wet tropics, our taxonomic knowledge of these trees is primarily based on the last revision of the five neotropical genera completed in 1937. The objective of this thesis was to perform a molecular and morphological study of the neotropical genera Compsoneura and Virola. To this end, I generated phylogenetic hypotheses, surveyed morphological and genetic diversity of focal species, and tested the ability of DNA barcodes to distinguish species of wild nutmegs. Morphological and molecular analyses of Compsoneura. indicate a deep divergence between two monophyletic clades corresponding to informal sections Hadrocarpa and Compsoneura. Although 23 loci were tested for DNA variability, only the trnH-psbA intergenic spacer contained enough variation to delimit 11 of 13 species sequenced. A morphological and molecular investigation of Compsoneura capitellata showed little discrete morphological variation among populations but significant genetic structure among populations. Phylogenetic analysis of Virola also revealed a deep molecular divergence between two clades having numerous contrasting morphologies. In contrast to Compsoneura, the trnH-psbA intergenic spacer failed to differentiate the majority of Virola species tested. An infraspecific morphological and molecular study of V. sebifera and V. loretensis showed that each of these species contains morphologically and ecologically discrete sympatric morphotypes that likely represent new species. In total, this investigation found 5 provisional new species from fewer than 600 collections at biological stations in Ecuador and Peru where these new species were among the most abundant trees in the forest. This suggests that much diversity likely remains to be described in the Myristicaceae and other tropical plant families.