Le but du présent travail est d’apporter la preuve paléontologique mettant en évidence que le clade Raninoida était bien établi dans le Néotropique durant la période Crétacée, où il était représenté par les plus anciennes familles ou par quelques–uns des plus anciens membres des plus anciennes familles. Je décris des taxa raninoïdiens ou similaires, incluant Archaeochimaeridae n. fam. et Archaeochimaera macrophthalma n. gen. n. sp., du Cénomanien supérieur (~95 Ma.) de Colombie (Chapitre 3), Planocarcinus n. gen., Planocarcinus olssoni (Rathbun, 1937) n. comb. et Notopocorystes kerri n. sp., de l’Aptien supérieur (~115 Ma.) de Colombie (Luque et al., accepté) (Chapitre 2). Ces taxa nouveaux, plus la présence de Cenomanocarcinus vanstraeleni Stenzel, 1945, dans l’Albien supérieur de Colombie (Vega et al., 2010), et d’Araripecarcinus ferreirai Martins–Neto, 1987, dans l’Albien du Brésil (Luque et al., en cours) (Chapitre 4), représentent certains des plus anciens signalements de quatre des sept familles raninoïdiennes, au moins, connues à ce jour. La nouvelle famile Archaeochimaeridae se présente comme le groupe frère du clade Raninidae + clade Symethidae. Cependant, la combinaison unique de caractères primitifs, dérivés et homoplasiques est inégalable chez les Raninoida, et, en fait, chez les autres sections de crabes podotrèmes. Alors que les taxa raninoïdiens du Crétacé sont bien connus aux latitudes élevées, les signalements en Amérique du Sud tropicale sont rares et épars, avec pour résultat de considérables distorsions pour traiter des importantes questions biogéographiques et phylogénétiques. Sur la base de données taxonomiques, paléobiogéographiques et cladistiques, une ré–appréciation des toute premières distributions spatio–temporelle des “crabes grenouilles” est proposée, avec pour objet de contribuer à une plus large compréhension de la diversité, phylogénie et évolution des premiers brachyoures au cours des âges. / The aim of the present work is to present new paleontological evidence that depicts the clade Raninoida well established in the Neotropics during Cretaceous times, as represented by the oldest, or some of the oldest members of its earliest families. I describe raninoid and raninoidid–like taxa including Archaeochimaeridae n. fam., and Archaeochimaera macrophthalma n. gen. n. sp., from the upper Cenomanian (~95 Ma.) of Boyacá, Planocarcinus n. gen., Planocarcinus olssoni (Rathbun, 1937) n. comb., and Notopocorystes kerri n. sp., from the upper Aptian (~115 Ma.) of Santander. These newly described taxa, plus the occurrence of Cenomanocarcinus vanstraeleni Stenzel, 1945, in the upper Albian of Boyacá (Vega et al., 2010), and Araripecarcinus ferreirai Martins–Neto, 1987, in the lower Albian of Brazil (Luque et al., in progress), represent the oldest records of, at least, four out of seven raninoidid families known to date. The new family Archaeochimaeridae, stands as the sister taxon to Raninidae + Symethidae clade. However, its unique combination of primitive, advanced, and homoplasic traits is matchless within Raninoida, and in fact, with the remaining podotreme sections. While Cretaceous raninoid taxa from higher latitudes are well known, records from the tropical South America are scarce and sparse, resulting in considerable biases when attempting to address major biogeographic and phylogenetic questions. Based on taxonomic, paleobiogeographic and cladistic information, some reconsideration of the early spatio–temporal distributions of frog crabs are proposed, with the aim of contributing to a broader understanding of the diversity, phylogeny, and evolution of early brachyuran crabs throughout time.

Orientador: Eric de Camargo Smidt / Resumo: O clado Ornithocephalus compreende 12 gêneros e 120 espécies e está distribuído do sul do México ao norte da Argentina, abrangendo regiões úmidas do oeste ao leste da América do sul. Embora o clado tenha sido recentemente foco de vários estudos filogenéticos, e seu monofiletismo não ser contestado, o arranjo de muitas espécies dentro do clado permanece desconhecido. Neste trabalho, investigamos o posicionamento das espécies de Centroglossa Barb.Rodr. Dunstervillea Garay e Zygostates Lindl. dentro do clado em foco, através de dados do DNA nuclear e plastidial, bem como dados morfológicos, por meio de análises de máxima verossimilhança, inferência bayesiana e máxima parcimônia. Encontramos uma relação filogenética estreita entre Dunstervillea e Eloyella P. Ortiz. sustentada por sinapomorfias morfológicas vegetativas e reprodutivas. Centroglossa e Zygostates aparecem intimamente relacionados em todas as análises, nas quais Centroglossa se mantem monofilético incluído em Zygostates. Através de análises em MEV de flores em desenvolvimento, identificamos a origem de apêndices florais, da tábula infraestigmática e do calo do labelo. Além disso, observamos em Zygostates e gêneros próximos, 26 características micromorfológicas e atividade secretora na flor em antese, que nos fornecem um maior número de caracteres e sustentam os clados gerados nas análises filogenéticas. No estado do Paraná, Zygostates possui 36 registros na Floresta Ombrófila Densa e Floresta Ombrófila Mista. Segundo ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The Ornithocephalus clade comprising 12 genera and 120 species and is distributed from southern Mexico to northern Argentina, covering wetlands from west to eastern South America. Although the clade has recently been the focus of several phylogenetic studies, and its monophyly is not disproved, the arrangement of many species within the clade remains unknown. In this work, we investigate the placement of Centroglossa Barb.Rodr., Dunstervillea Garay and Zygostates Lindl. species within the clade in focus, using nuclear and plastid DNA data, as well as morphological data, through maximum likelihood, Bayesian inference and maximum parsimony analyzes. We found a close phylogenetic relationship between Dunstervillea and Eloyella P. Ortiz. supported by vegetative and reproductive morphological synapomorphies. Centroglossa and Zygostates appear closely related in all analyses, where Centroglossa remains monophyletic included in Zygostates. Based in analysis of SEM of development flowers, we identified the origin of floral appendages, tabula infrastigmatica and the lip callus. Through the same analysis, we observed in Zygostates and close genera, 26 micromorphological characteristics and secretory activity in the flower anthesis, which provide us a larger number of characters and support the clades generated in phylogenetic analyzes. In the state of Paraná, Zygostates has 36 records in Floresta Ombrófila Densa and Floresta Ombrófila Mista. According to IUCN criteria, Zygostates allen... (Complete abstract click electronic access below) / Doutor

The present study deals with the largely unknown Peperomia subgenus Tildenia. Chapter 1 focuses on the South American centre of Tildenia biodiversity. Initially a general rectified description of Peperomia subgenus Tildenia is presented based on the latest molecular analyses. Fourteen new species are described together with two formerly published varieties that are raised to species rank. Furthermore, for one name, basionym rejection and lectotypification are proposed. All valid species from the South American centre of diversity are treated in a phylogenetic framework. A comparable study of the North American centre of diversity is presented in Chapter 2 including a key to all Tildenia species from Mexico and Central America and the description of thirteen new species (one former variety). The new descriptions within this study doubles the species number of subgenus Tildenia. Chapter 3 is a biogeographical study comprising the whole distribution area revealing the place of origin and the age of Peperomia subgenus Tildenia. The appearance of the major lineages of the subgenus is examined against the background of orogeny and climate changes in the respective distribution areas, to retrace the evolutional driving forces of this plant group. In Chapter 4 Tildenia is used as a model group for the characterisation of a new nuclear single copy gene applicable for general use for phylogentic resoltution on species level and below.

No description available.

The relative contributions of biome history and geological setting to historical assembly of species richness in biodiversity hotspots remain poorly understood. The tropical Andes is one of the world’s top biodiversity hotspots, and with its diverse biomes and the relatively recent but dramatic uplift, the Andes provides an ideal study system to address these questions. To gain insights into the historical species assembly of the tropical Andes, this study focuses on investigating patterns of plant species diversification in the Andean seasonally dry tropical forest (SDTF) biome. Three plant genera are used as study groups: Amicia (Leguminosae, Papilionoideae), Tecoma (Bignoniaceae), and Mimosa (Leguminosae, Mimosoideae). Species limits are re-evaluated to enable dense sampling of species and intraspecific diversity for phylogeny reconstruction for each group. Time-calibrated phylogenies for Amicia and Mimosa are presented and used to determine patterns of species diversification in time and space. For Tecoma, incongruence between nuclear and chloroplast gene trees precludes straightforward estimation of a species tree and this incongruence is attributed to possible reticulation caused by hybridization. Divergence time estimates and patterns of diversification for Amicia and Mimosa are compared with other Andean SDTF groups (Cyathostegia, Coursetia, Poissonia; Leguminosae) using isolation by distance and phylogenetic geographic structure analyses. Consistently deep divergences between sister species and high geographic structure across all five groups suggest that Andean SDTF lineages have persisted over the past 10 million years (My) with high endemism driven by dispersal limitation, caused by geographic isolation, following the most recent episode of rapid mountain uplift 5-10 My ago. This prolonged stasis of the Andean SDTF biome is in line with Miocene fossil and paleoclimate evidence. Finally, wider analyses of the contrasting evolutionary timescales of older SDTF and more recent high-altitude grassland diversity suggest that the exceptional plant species diversity in the Andes is the outcome of highly heterogeneous evolutionary histories reflecting the physiographical heterogeneity of the Andean biodiversity hotspot.

Radiações evolutivas estão entre os eventos mais fascinantes da evolução. Grande parte da diversidade da vida, tanto de espécies como ecológica, surgiu nos breves intervalos temporais de rápida especiação que configuram as radiações. As causas ecológicas e não-ecológicas do surgimento da diversidade em radiações evolutivas, em especial nas radiações adaptativas, são tema de pesquisa há muito tempo, pelo menos desde que Darwin observou a imensa diversidade de um grupo de pássaros nas ilhas Galápagos. Desde então, as ilhas têm sido os ambientes ideais para o estudo desse fenômeno, e foi a partir das observações e experimentos em ilhas que toda a teoria ecológica das radiações evolutivas surgiu. Contudo, as causas ecológicas das radiações explosivas ocorridas em amplas escalas continentais permanecem tema de constante debate. Nesta tese, foram investigados os determinantes ecológicos e não-ecológicos (e.g., geografia, contingências históricas, efeitos filogenéticos) da evolução morfológica dos roedores sigmodontíneos durante sua radiação na região Neotropical, em especial no continente sul-americano. Para isso, foi quantificada a morfologia do crânio e mandíbula de mais de dois mil exemplares do grupo, e foram investigadas variações ecomorfológicas nos níveis interespecífico (I), intraespecífico (II), e entre assembleias de sigmodontíneos (III). Na Parte I da tese, foram investigadas duas predições da teoria da radiação adaptativa, a correlação-fenótipo ambiente (capítulo 1) e a funcionalidade do fenótipo através da força da mordida (capítulo 2), permitindo determinar o papel da divergência ecológica na evolução morfológica das espécies. Na Parte II (capítulo 3), foram investigadas as contribuições relativas de processos determinísticos e neutros sobre a variação morfológica entre populações de uma espécie de roedor sigmodontíneo amplamente distribuída, Akodon cursor. Na Parte III, a influência da variação ambiental e da distribuição espacial das linhagens filogenéticas de sigmodontíneos sobre o tamanho corporal (capítulo 4) e forma do crânio e mandíbula (capítulo 5), foram investigados no contexto biogeográfico da variação no tamanho e forma média entre assembleias de sigmodontíneos. As contribuições originais desta tese foram: (i) mostrar que a radiação evolutiva dos roedores sigmodontíneos foi guiada principalmente por fatores históricos e geográficos ao invés de fatores ecológicos; (ii) sugerir que radiações evolutivas ocorridas em escalas continentais, especialmente de roedores, têm um componente geográfico e histórico mais determinante do que o componente ecológico; (iii) revelar que a força da mordida varia pouco entre roedores sigmodontíneos herbívoros e granívoros, o que provavelmente é resultado do fenótipo generalista desses roedores; (iv) apontar que sigmodontíneos com dieta insetívora têm uma taxa de evolução mais rápida, e parecem estar evoluindo sua forma do crânio/mandíbula e sua força da mordida em uma direção diferente das demais espécies; (v) demonstrar que, dentro de uma espécie de sigmodontíneo (Akodon cursor), fluxo gênico e deriva genética explicam melhor a forma do crânio entre populações, enquanto a variação ambiental explica melhor o tamanho do crânio, indicando que o tamanho é uma característica mais lábil e mais sujeita a pressões ambientais do que a forma do crânio; (vi) mostrar que a variação biogeográfica, tanto do tamanho quanto da forma média do crânio/mandíbula entre assembleias de sigmodontíneos, está sob influência da distribuição diferencial das linhagens filogenéticas ao longo do espaço geográfico, bem como de variáveis ambientais; o que indica conservação filogenética de nicho à nível de metacomunidades. De modo geral, ao investigar as contribuições relativas dos componentes adaptativo e não-adaptativo da evolução morfológica, foram obtidas informações importantes para conhecer as causas da diversificação morfológica em Sigmodontinae, aumentando nosso conhecimento sobre as origens de toda a diversidade biológica. / Evolutionary radiations are among the most fascinating phenomena of evolution. Most of the biological diversity on the planet, both in terms of species and ecological diversity, appeared during these brief intervals of rapid speciation. The ecological and non-ecological causes of the emergence of diversity in evolutionary radiations, especially in adaptive radiations, have long been the subject of research, beginning with Darwin and his notice of the astonishing diversity of bird forms in the Galapagos Islands. Islands have since been ideal environments in which to study evolutionary and adaptive radiations, and indeed it was from observations and experiments on islands that all ecological theory of evolutionary radiations arose. However, the ecological causes of explosive radiations occurring on large continental scales are still a matter of debate. In this dissertation, I investigated the ecological and non-ecological (e.g., geography, historical contingencies, phylogenetic effects) determinants of morphological evolution in sigmodontine rodents during their radiation in the Neotropical region, particularly on the South-American continent. The skull and mandible morphology of more than two thousand specimens was quantified, and ecomorphological variation was investigated on three levels: interspecific (I), intraspecific (II), and among sigmodontine assemblages (III). In part I, two predictions from the ecological theory of adaptive radiation were investigated: the phenotype-environment correlation (chapter 1), and the trait utility through the bite force (chapter 2). This approach enabled determination of the role of ecological divergence in species morphological evolution. In part II (chapter 3), I investigated the relative contributions of deterministic and neutral processes to morphological variation among populations of one widely distributed sigmodontine species, Akodon cursor. In part III, I investigated the influence of environmental variation and spatial distribution of phylogenetic lineages on body size (chapter 4) and on shape of the skull and mandible (chapter 5), in the context of biogeographical variation of mean size and shape in sigmodontine assemblages. The original contributions of this dissertation are as follows: (i) to demonstrate that the evolutionary radiation of sigmodontines was driven mainly by historical and geographical factors instead of ecological factors; (ii) to suggest that evolutionary radiations on continental scales, especially rodent radiations, have a more determinant historical and geographical component than an ecological one; (iii) to show small variation in bite force between sigmodontine herbivores and granivores, which is likely a consequence of the generalist phenotype of these rodents; (iv) to highlight that insectivorous sigmodontines have a faster rate of morphological evolution than other diet groups, and that skull and mandible morphology and bite force are evolving in different directions than in other species; (v) to demonstrate that within a sigmodontine species (Akodon cursor), gene flow and genetic drift better explain variation in skull shape among populations, while environmental variation better explains variation in skull size, which suggests that size is more labile feature than shape and thus more prone to change with environmental pressures; and (vi) to show that biogeographical variation in mean body size, mean skull shape, and mean mandible shape across sigmodontine assemblages is influenced by the different distributions of phylogenetic lineages over geographical space, as well by environmental variables, which indicates phylogenetic niche conservatism at the metacommunity level. These results shed light on some of the factors driving morphological diversification in Sigmodontinae. Further, the analytical approach(es) utilized may be useful for general investigations of the relative contributions of adaptive and non-adaptive components of morphological evolution, thereby potentially increasing our knowledge of the origins of all biological diversity.

Introdução - Culex quinquefasciatus é um mosquito sinantrópico que causa incômodo à população humana e é relacionado com a transmissão de nematóides ou arbovírus em áreas endêmicas, respectivamente, do litoral brasileiro e da América Central ou do Norte. Culex nigripalpus é um mosquito hemi-sinantrópico que possui a capacidade de se dispersar para as áreas antrópicas e transmitir Saint Louis Virus e Equine Encephalitis Virus, respectivamente, na América do Norte e Venezuela. Objetivo - Caracterizar o hábito alimentar de Culex nigripalpus e a densidade, a sobrevivência e o hábito alimentar de Culex quinquefasciatus no Parque Ecológico do Tietê (PET), São Paulo. Métodos - O PET é uma Área de Preservação Ambiental com animais residentes ou migratórios. As amostras de mosquitos adultos foram coletadas, mensalmente, em quatro áreas no PET, durante um ano e por meio de aspirador à bateria. O método de ELISA indireto foi empregado para a identificação do hospedeiro que é fonte alimentar ao mosquito. A densidade da população de Cx. quinquefasciatus foi estimada pelo método de marcação, soltura e recaptura na vegetação da margem de um canal no PET. Amostras de fêmeas de Cx. quinquefasciatus desse local foram dissecadas ou acompanhadas em laboratório para estimativa da taxa de sobrevivência. Resultados – A proporção de repastos sangüíneos de Cx. quinquefasciatus e de Cx. nigripalpus foi, respectivamente, 6,5 e 8,3% em humanos, 18,8 e 27,7% em cães, 7,4 e 2,3% em galinhas, 2,8 e 9,0% em ratos, 3,2 e 8,3% em múltiplos hospedeiros e 67,7 e 60,9% em hospedeiros não identificados. Human Blood Index para Cx. quinquefasciatus e Cx. nigripalpus foi, respectivamente, 0,20 e 0,17. Feeding Index entre os hospedeiros homem/cão, homem/galinha e homem/rato foi, respectivamente, 0,35, 0,63 e 2,65 para Cx. quinquefasciatus e 0,30, 2,56 e 1,05 para Cx. nigripalpus. A distribuição de repastos sangüíneos teve associação significante estatisticamente com as fêmeas de Cx. nigripalpus em estádio de Sella 2 coletadas em todas as áreas do PET. A densidade de Cx. quinquefasciatus para uma área de 2.520 m2 foi 7.262±1.537. A proporção de paridas, a duração do ciclo gonotrófico e a taxa de sobrevivência foram, respectivamente, igual a 0,48, 4,75 (CL 95% = 4,3-5,2) e 0,86, estimados para a população de Cx. quinquefasciatus. Conclusões – Cães e galinhas foram hospedeiros importantes para Cx. quinquefasciatus, enquanto que cães foram hospedeiros importantes para Cx. nigripalpus. O repasto sangüíneo é mais bem detectado pelo ELISA indireto em fêmeas no estádio de Sella 2. A sobrevivência e a densidade de Cx. quinquefasciatus indicam que essa espécie é epidemiologicamente relevante na área do PET como espécies vetora ou peste urbana. Essa espécie deve ser objetivo do programa de controle de vetores no município de São Paulo. / Introduction - Culex quinquefasciatus has high synanthropy, infest human dwellings and is vector of nematoids and arbovirus from endemic areas, respectively, in Brazilian coast and in Central or North America. Culex nigripalpus has average synanthropy and can disperse through the anthropic environment carrying Saint Louis Virus and Equine Encephalitis Virus, respectively, in North America and Venezuela. Objective - To characterize host-feeding habit of Culex nigripalpus and density, survival and host-feeding habit of Culex quinquefasciatus in the Parque Ecológico do Tietê (PET), São Paulo. Methods - The PET is an Area of Environmental Protection with resident or migratory animals. The samples of adult mosquitoes were collected, monthly, in four areas in the PET, during one year and by means of a backpack battery aspirator. An indirect ELISA technique was used for the identification of the host that is an alimentary source for the mosquito species. The density of Cx. quinquefasciatus population was estimated using the Mark, Release and Recapture method on the vegetation of the edge of a canal in the PET. Samples of females of Cx. quinquefasciatus from this place were dissected or followed in laboratory for estimating the survival rate. Results – Cx. quinquefasciatus and Cx. nigripalpus fed on human 6.5 and 8.3%, dog 18.8 and 27.7%, chicken 7.4 and 2.3%, rat 2.8 and 9.0%, multiple hosts 3.2 and 8.2% and unidentified hosts 67.9 and 60.9%, respectively. The unweighted human blood index (HBI) values were 0.20 for Cx. quinquefasciatus and 0.17 for Cx. nigripalpus populations. The feeding index values between the hosts human/dog, human/chicken and human/rat were, respectively, 0.35, 0.63 and 2.65 for Cx. quinquefasciatus and 0.30, 2.56 and 1.05 for Cx. nigripalpus. The distributions of blood-meals had statistically significant association on Sella 2 stage of the Cx. nigripalpus collected in all areas at the PET. The density of Cx. quinquefasciatus for an area of 2,520 m2 was 7,262±1,537. The proportion of parous, gonotrophic cycle length and survival rate were, respectively, equal to 0.48, 4.75 (CL 95% = 4.3-5.2) and 0.86, for Cx. quinquefasciatus population. Conclusions – Dogs and chickens are important hosts for Cx. quinquefasciatus, whereas dog is an important host for Cx. nigripalpus. The host-blood of females in Sella 2 stage increases sensibility of the indirect ELISA assay. The survivorship and the density of Cx. quinquefasciatus indicate that these species are epidemiologically relevant in the PET area as either a pest or vector species. Those species should be a goal of the vector control program of Sao Paulo municipality.

A fim de avaliar a diversidade genética, morfológica e filogeografia de tripanossomas de leptodactilídeos, analisamos diversos isolados encontrados em amostras de sangue e fígados obtidos no Brasil (Amazônia, Caatinga, Cerrado, Mata Atlântica e Pantanal), na Colômbia e na Venezuela. Inferências filogenéticas baseadas em marcadores moleculares (V7V8 SSUrDNA e gGAPDH) demonstraram uma complexa associação entre clados, biomas e hospedeiros vertebrados. Nossos resultados corroboram a monofilia dos trypanossomas de anuros e sugerem a existência de, ao menos, seis clados (An01-06) nesse grupo com 12 candidatos a novas espécies. O clado An01 compreende tripanossomas de leptodactilídeos e hilídeos de todos os biomas. Os clados An02, An05 e An06 são formados, predominantemente, por tripanossomas de leptodactlídeos de diferentes biomas brasileiros, da Colômbia e da Venezuela. O clado An03 é formado por tripanossomas de leptodactilídeos, bufonídeos e flebotomíneos, todos do bioma amazônico. O clado An04 agrupa apenas tripanossoma exóticos da América do Norte, África e Europa. / Aiming to investigate the genetic diversity, the morphology and the phylogeny of leptodactylid trypanosomes, we analyzed a number of trypanosomes from blood and liver samples from Brazil (Amazonia, Caatinga, Cerrado, Atlantic Forest and Pantanal), Colombia and Venezuela. Phylogenetic analyses based on molecular markers (V7V8 SSUrDNA and gGAPDH) demonstrated a complex association between clades, biomes and vertebrate hosts. Our results corroborated the monophyly of anuran trypanosomes and suggested the existence of, at least, six clades (An01-06) inside the anuran clade with 12 candidate new species. Clade An01 groups trypanosomes from leptodactylids and hylids collected in all biomes. Clades An02, An05 and An06 are composed, mostly, by leptodactylid trypanosomes from several Brazilian biomes, Colombia and Venezuela. Clade An03 aggregates parasites from leptodactylids, bufonids and phlebotomines from Amazonia. Clade An04 groups only exotic trypanosome species from North America, Africa and Europe.

Three new species of cichlid fishes of the genus Geophagus, part of the Neotropical subfamily Geophaginae, are described from the Orinoco and Casiquiare drainages in Venezuela. Phylogenetic relationships among 16 genera and 30 species of Geophaginae are investigated using 136 morphological characters combined with DNA sequences coding for the mitochondrial gene NADH dehydrogenase subunit 4 (ND4) and the nuclear Recombination Activating Gene 2 (RAG2). Data from previous studies are integrated with the new dataset by incorporating published DNA sequences from the mitochondrial genes cytochrome b and 16S and the microsatellite flanking regions Tmo-M27 and Tmo-4C4. Total-evidence analysis revealed that Geophaginae is monophyletic and includes eighteen genera grouped into two major clades. In the first clade, the tribe Acarichthyini (genera Acarichthys and Guianacara) is sister-group to a clade in which Gymnogeophagus, 'Geophagus' steindachneri, and Geophagus sensu stricto are sister to 'Geophagus' brasiliensis and Mikrogeophagus; all these are in turn sister-group to Biotodoma, Dicrossus and Crenicara. In the second clade, Satanoperca, Apistogramma (including Apistogrammoides), and Taeniacara are sister to Crenicichla and Biotoecus. Monophyly and significantly short branches at the base of the phylogeny indicate that genera within Geophaginae differentiated rapidly within a relatively short period. High morphological, ecological, and behavioral diversity within the subfamily suggest that geophagine divergence may be the result of adaptive radiation.

Three new species of cichlid fishes of the genus Geophagus, part of the Neotropical subfamily Geophaginae, are described from the Orinoco and Casiquiare drainages in Venezuela. Phylogenetic relationships among 16 genera and 30 species of Geophaginae are investigated using 136 morphological characters combined with DNA sequences coding for the mitochondrial gene NADH dehydrogenase subunit 4 (ND4) and the nuclear Recombination Activating Gene 2 (RAG2). Data from previous studies are integrated with the new dataset by incorporating published DNA sequences from the mitochondrial genes cytochrome b and 16S and the microsatellite flanking regions Tmo-M27 and Tmo-4C4. Total-evidence analysis revealed that Geophaginae is monophyletic and includes eighteen genera grouped into two major clades. In the first clade, the tribe Acarichthyini (genera Acarichthys and Guianacara) is sister-group to a clade in which Gymnogeophagus, 'Geophagus' steindachneri, and Geophagus sensu stricto are sister to 'Geophagus' brasiliensis and Mikrogeophagus; all these are in turn sister-group to Biotodoma, Dicrossus and Crenicara. In the second clade, Satanoperca, Apistogramma (including Apistogrammoides), and Taeniacara are sister to Crenicichla and Biotoecus. Monophyly and significantly short branches at the base of the phylogeny indicate that genera within Geophaginae differentiated rapidly within a relatively short period. High morphological, ecological, and behavioral diversity within the subfamily suggest that geophagine divergence may be the result of adaptive radiation.