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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.
21

Diverzita a taxonomie zástupců rodu Geastrum ve Střední Americe / Diversity and taxonomy of members of genus Geastrum in Central America

Zehnálek, Petr January 2017 (has links)
In temperate zone, especially Europe and North America, is the genus Geastrum very well inspected group of Gasteromycetes with long lasting and comprehensive history of research. Our knowledge of the diversity in other areas of distribution, especially in tropics, is more than limited. The aim of this diploma thesis is to contribute for cognition of diversity of this genus in Panama, Costa Rica and Colombia I have collected 86 samples belonging to genus Geastrum during three expeditions to Panama (Chiriqué province) in the years 2015, 2016, 2017. I have characterized those based on morphological and molecular data. I have also studied morphology of 40 borrowed herbarium specimens from Costa Rica, Colombia and Panama. I have successfully sequenced four locuses of DNA from my own samples (ITS, LSU, RPB1 and ATP6). This method had lover efficiency in herbarium specimens due to present contaminations, age of specimens or probably badly stored. Molecular phylogenetic analysis was carried out by Bayesian method and its results have in agreement with morphologic traits shown many lineages new for Panama and moreover at least four new species completely new to science. Variability in species complexes (e.g. G. lageniforme, G. saccatum, G. velutinum) is presented in more detail with emphasis to lineages...
22

Connectivity of fragmented amphibian populations in a Neotropical landscape

Nowakowski, Aaron J 06 May 2014 (has links)
A high proportion of amphibian species are threatened with extinction globally, and habitat loss and degradation are the most frequently implicated causes. Rapid deforestation for the establishment of agricultural production is a primary driver of habitat loss in tropical zones where amphibian diversity is highest. Land-cover change affects native assemblages, in part, through the reduction of habitat area and the reduction of movement among remnant populations. Decreased gene flow contributes to loss of genetic diversity, which limits the ability of local populations to respond to further environmental changes. The focus of this dissertation is on the degree to which common land uses in Sarapiquí, Costa Rica impede the movement of two common amphibian species. First, I used field experiments, including displacement trials, and a behavioral landscape ecology framework to investigate the resistance of pastures to movement of Oophaga pumilio. Results from experiments demonstrate that pastures do impede movement of O. pumilio relative to forest. Microclimatic effects on movement performance as well as limited perceptual ranges likely contribute to reduced return rates through pastures. Next, I linked local processes to landscape scale estimates of resistance. I conducted experiments to measure habitat-specific costs to movement for O. pumilio and Craugastor bransfodrii, and then used experimental results to parameterize connectivity models. Model validation indicated highest support for resistance estimates generated from responses to land-use specific microclimates for both species and to predator encounters for O. pumilio. Finally, I used abundance and experiment-derived resistance estimates to analyze the effects of prevalent land uses on population genetic structure of the two focal species. While O. pumilio did not exhibit a strong response to landscape heterogeneity and was primarily structured by distances among sites, C. bransfordii genetic variation was explained by resistance estimates from abundance and experiment data. Collectivity, this work demonstrates that common land uses can offer different levels of resistance to amphibian movements in Sarapiquí and illustrates the value of investigating local scales processes to inform interpretation of landscape-scale patterns.
23

Filogeografia de Drosophila sturtevanti (Diptera : Drosophilidae) em biomas neotropicais /

Zorzato, Samara Videira January 2019 (has links)
Orientador: Lilian Madi-Ravazzi / Resumo: As mudanças climáticas ocorridas no Pleistoceno afetaram a distribuição e os padrões de diversificação populacionais e são conhecidas como um dos potenciais impulsionadores da alta diversidade encontrada na região Neotropical. Drosophila sturtevanti pertence ao subgrupo sturtevanti do grupo saltans de Drosophila e é uma das espécies com distribuição geográfica mais ampla dentro do grupo, ocorrendo em áreas florestais de diferentes biomas. Além disso, essa espécie apresenta altos níveis de variabilidade genética para diversos marcadores, constituindo um excelente modelo para estudos de estrutura populacional, diversificação e adaptação em diferentes cenários. O objetivo desse estudo foi analisar a diferenciação genética, usando os genes Citocromo Oxidase subunidades I e II em 163 indivíduos provenientes de 21 populações de D. sturtevanti coletados em fragmentos florestais da América Central ao sul do Brasil, com ênfase na Mata Atlântica. Nossos resultados moleculares mostram que as populações de D. sturtevanti estão estruturadas na América do Sul e sua distribuição mostra uma correlação significativa com variáveis geográficas e climáticas, principalmente temperatura e umidade. Além disso, os eventos de divergência entre os grupos geográficos sugerem associação significante com as oscilações paleoclimáticas ocorridas desde o Pleistoceno tardio e, esses eventos, provavelmente moldaram a distribuição geográfica dos haplogrupos de acordo com variáveis ambientais, principalmente te... (Resumo completo, clicar acesso eletrônico abaixo) / Doutor
24

The Impact of Human Presence on Terrestrial Mammals in Secondary Regenerating Forest of the Peruvian Amazon

Pandya, Duncan January 2023 (has links)
Human disturbance is becoming an ever-bigger threat to biodiversity across the globe and should continue to be a field of conservation priority. Urbanisation, research and tourism put unavoidable pressure on the surrounding flora and fauna, therefore we need to gain knowledge on how to reduce future harm. Here we investigated the effects of human presence on medium-large terrestrial mammals in the south-eastern Peruvian Amazon, using camera traps to measure the number of human and mammal observations at varying distances from our research centre and the hiking trails. Species richness and the Shannon and Inverse Simpson diversity indices were also calculated during the four-month study period. Nineteen species were detected across fourteen camera sites. Distance from camp was positively correlated with species richness and the diversity indices, but showed no correlation with total mammal observations. Distance from nearest trail was negatively correlated with species richness, total mammal observations and the diversity indices. Total human observations was negatively correlated with species richness and the diversity indices, but had no impact on total mammal observations. Nevertheless, these results often had high p-values and low sample size and therefore should be interpreted with caution. Omnivores were the most sensitive trophic guild, showing a statistically significant negative correlation with total human observations, and a statistically significant positive correlation with distance from nearest trail. It is important then to assess these responses to human disturbance at the community and species level, as to truly understand the impact we are having.
25

The evolution of the advertisement call in glassfrogs (Centrolenidae Taylor, 1951)

Sulbar?n, Mois?s David Escalona 28 March 2018 (has links)
Submitted by PPG Zoologia (zoologia-pg@pucrs.br) on 2018-09-13T17:02:53Z No. of bitstreams: 1 Disserta??o - Escalona - Mois?s.pdf: 3628906 bytes, checksum: a6fc5f6bc6015a1a1a95f67e3c5c5f16 (MD5) / Approved for entry into archive by Sheila Dias (sheila.dias@pucrs.br) on 2018-09-14T17:19:08Z (GMT) No. of bitstreams: 1 Disserta??o - Escalona - Mois?s.pdf: 3628906 bytes, checksum: a6fc5f6bc6015a1a1a95f67e3c5c5f16 (MD5) / Made available in DSpace on 2018-09-14T17:46:57Z (GMT). No. of bitstreams: 1 Disserta??o - Escalona - Mois?s.pdf: 3628906 bytes, checksum: a6fc5f6bc6015a1a1a95f67e3c5c5f16 (MD5) Previous issue date: 2018-03-28 / Conselho Nacional de Pesquisa e Desenvolvimento Cient?fico e Tecnol?gico - CNPq / Os anuros emitem cantos de an?ncio com o objetivo de atrair parceiros e repelir concorrentes co-espec?ficos. Eu investiguei a associa??o entre o comprimento do corpo, o s?tio de vocaliza??o, o cuidado parental e a varia??o em propriedades ac?sticas do canto (dura??o do canto, n?mero de notas, freq??ncia de pico, largura de banda de freq??ncia e estrutura do canto) em pererecasde-vidro?uma fam?lia de pererecas que habitam florestas neotropicais?controlando para efeitos de ancestralidade compartilhada. Eu tamb?m explorei o tempo e o modo de evolu??o dessas caracter?sticas e as comparei com as de tr?s caracter?sticas morfol?gicas (comprimento do corpo, largura da cabe?a e comprimento da t?bia). Eu gerei e compilei dados ac?sticos para 72 esp?cies de pererecas-de-vidro (46 % da riqueza descrita), incluindo representantes de todos os g?neros, e analisei os dados usando m?todos comparativos filogen?ticos. Descobri que quase todas as caracter?sticas ac?sticas avaliadas tinham sinal filogen?tico significativo, mas geralmente modesto. O pico de frequ?ncia dos cantos ? significativamente associado ao comprimento do corpo, enquanto a estrutura dos cantos ? significativamente associada ao s?tio de vocaliza??o e ao sexo do adulto que desempenha cuidado-parental. Meus resultados sustentam que, al?m das restri??es filogen?ticas, o tamanho do corpo est? associado ? evolu??o dos cantos de an?ncio em Centrolenidae. A diversifica??o de caracter?sticas ac?sticas ao longo da filogenia de pererecas-de-vidro concorda com a radia??o dos taxa na transi??o entre Mioceno e Plioceno. A disparidade estimada para caracter?sticas ac?sticas foi geralmente maior que a de caracter?sticas morfol?gicas, e o pico de disparidade de caracter?sticas ac?sticas geralmente ocorreu mais tarde na evolu??o do grupo, sugerindo um in?cio historicamente recente da pronunciada diverg?ncia ac?stica entre esp?cies deste clado. / Anurans emit advertisement calls with the purpose of attracting mates and repelling conspecific competitors. I investigated the association between body size, calling site and parental care with call variables (call duration, number of notes, peak frequency, frequency bandwidth and call structure) in glassfrogs?a family of leaf-dwelling frogs which inhabit Neotropical forests?while controlling for effects of shared ancestry. I also explored the tempo and mode of evolution of these traits and compared them with those of three morphological traits (snout-vent length, and relative head width and tibia length). I generated and compiled acoustic data for 72 glassfrog species (46 % of described diversity), including representatives of all genera (n = 12), and analyzed the data using phylogenetic comparative methods. I found that almost all acoustic traits evaluated had significant, but generally modest phylogenetic signal. Peak frequency of calls is significantly associated with body-size, while call structure is significantly associated with calling site and with the sex of the caring parent. My results support that, besides phylogenetic constraints, body size is associated with the evolution of advertisement calls in glassfrogs. Diversification of acoustic traits along the phylogeny of glassfrogs is coincident with the radiation of extant taxa at the Miocene-Pliocene boundary. The estimated disparity of acoustic traits was larger than that of morphological traits and the peak in disparity of acoustic traits generally occurred later in the evolution of glassfrogs, suggesting a historically recent outset of the pronounced acoustic divergence in this clade.
26

Species Limits, and Evolutionary History of Glassfrogs

Castroviejo-Fisher, Santiago January 2009 (has links)
Recognizing the mechanisms of speciation and the limits of species is essential to understand the origin of biodiversity and how to conserve it. The general aims of my investigations during my doctoral studies were two-fold: to study evolutionary patterns and processes, and to provide specific and superspecific taxonomic classifications that try to reflect evolutionary history. I have focused my research on anurans in their biodiversity hotspot, the American Tropics. I have used morphological, behavioral (mating calls), and genetic (DNA sequences) characters to study species boundaries between frogs of the genus Pristimantis and the family Centrolenidae (glassfrogs). The results show that the exclusive use of single lines of evidence or the application of arbitrary thresholds impair and bias our ability to recognize new species and limit the possibility to understand evolutionary processes. Only an integrative approach combining every source of evidence provides the necessary feedback to discover all species and test their identity by comparing independent sets of data. This approach further allows identifying those species that probably represent stable comparative units (well supported species hypotheses) and to flag taxa that require further assessment. Phylogenetic reconstructions based on seven nuclear and mitochondrial genes for about 100 species of glassfrogs revealed that previous hypotheses of relationships were mislead by rampant convergent evolution at the phenotypic level. None of the previously suggested classifications fit with the reconstructed evolutionary history. Consequently, we proposed a new classification consistent with this phylogeny. I also studied the tempo and mode of diversification among glassfrogs. Based on sequences from ten genes in 87 species, I estimated species divergence times, age-range correlation between sister species, and reconstructed ancestral areas and dispersal/vicariance events. The results revealed a complex model of diversification where geographical isolation seems to be the dominant scenario for speciation and only clades of altitudinal generalists have been able to spread across the Neotropical rainforests.
27

Taxonomy, biogeography and phylogeny of Cretaceous frog crabs (Crustacea, Decapoda, Brachyura) from the Neotropics

Luque, Javier 12 1900 (has links)
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.
28

Systematic and Evolution of Peperomia subgenus Tildenia (Piperaceae)

Symmank, Lars 20 October 2011 (has links) (PDF)
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.
29

Trepadeiras em afloramentos rochosos no Nordeste oriental do Brasil

LUCENA, Danielly da Silva 09 March 2016 (has links)
Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2017-05-02T13:22:41Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Danielly Lucena - Dissertação- PPGBV - 2016.pdf: 2752132 bytes, checksum: cf03071cfad4402b388e0792b1b6f4a2 (MD5) / Made available in DSpace on 2017-05-02T13:22:42Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Danielly Lucena - Dissertação- PPGBV - 2016.pdf: 2752132 bytes, checksum: cf03071cfad4402b388e0792b1b6f4a2 (MD5) Previous issue date: 2016-03-09 / CAPES / O presente trabalho objetivou reconhecer a composição florística e o espectro biológico das espécies trepadeiras ocorrentes em dois afloramentos rochosos no estado de Pernambuco, assim como, analisar a composição florística e síndromes de dispersão, e determinar a influência de fatores abióticos na riqueza de trepadeiras em afloramentos rochosos inseridos em diferentes formações vegetacionais do Nordeste oriental do Brasil. Foi realizado o levantamento florístico do hábito trepador em dois afloramentos rochosos do estado de Pernambuco, nos municípios de Bezerros (Pedra do Cruzeiro) e Triunfo (Pico do Papagaio), através de coletas botânicas períodicas em cada área. Os dados para reconhecimento da composição e similaridade florística, assim como, avaliação da influência de fatores abióticos na riqueza de espécies, foram obtidos de inventários florísticos previamente publicados e referentes a 15 áreas de afloramentos rochosos, localizados nos estados da Paraíba e Pernambuco. Com base nos dados dos dois afloramentos inventariados foram identificadas 58 espécies, 39 gêneros e 20 famílias botânicas. O espectro biológico predominante foi o fanerófito (80%). Dentre as espécies, 62% são amplamente distribuídas e ocorrem nos três domínios fitogeográficos do Nordeste (Caatinga, Cerrado e Mata Atlântica). A composição florística das 15 áreas de afloramentos rochosos avaliadas foi de 147 espécies, distribuídas em 67 gêneros e 25 famílias botânicas. Neles a autocoria foi a síndrome de dispersão com maior destaque entre as espécies (44%). Três grupos florísticos foram identificados e dentre os fatores analisados, distância geográfica e tipos de vegetação circundante são os principais responsáveis pela composição florística e agrupamento entre as áreas. A riqueza de espécies apresentou correlação positiva com altitude e negativa com a distância da costa e temperatura, a riqueza de trepadeiras herbáceas apresentou correlação negativa com a precipitação, enquanto a riqueza de trepadeiras lenhosas se manteve constante com a precipitação. As espécies identificadas, apesar de amplamente distribuídas, respondem a um padrão florístico de acordo com os tipos vegetacionais onde os afloramentos rochosos estão inseridos. / This study aimed to recognize the floristic composition and biological spectrum of species of climbing plants occurring in two rock outcrops in the state of Pernambuco, as well as analyze the floristic composition and dispersal syndromes, and determine the influence of abiotic factors on the richness of climbers on rock outcrops inserted in different vegetation formations of the eastern portion of the Brazilian Northeast. The floristic survey of climbers was carried out on two rock outcrops of Pernambuco state, in the municipalities of Bezerros (Pedra do Cruzeiro) and Triunfo (Pico do Papagaio), through periodic botanical collections in each area. Data for recognition of the floristic composition and similarity, as well as for the evaluation of the influence of abiotic factors on species richness, were obtained from previously published floristic inventories relating to 15 areas of rock outcrops, located in the states of Paraíba and Pernambuco. Based on data from the two outcrops inventoried 58 species were identified, belonging to 39 genera and 20 botanical families. The predominant biological spectrum was phanerophyte (80%). Among the species, 62% are widely distributed and occur in the three phytogeographical domains occurring in the Northeast (Caatinga, Cerrado and Atlantic Forest). The floristic composition of the 15 areas of rock outcrops evaluated included 147 species belonging to 67 genera and 25 botanical families. Autochory was the predominant dispersal syndrome among species (44%). Three floristic groups were identified and among the factors analyzed, geographic distance and types of surrounding vegetation are primarily responsible for the floristic composition and grouping among the areas. Species richness was positively correlated with altitude and negatively with distance from shore and temperature, the richness of herbaceous vines was negatively correlated with precipitation, while the richness of woody vines remained constant with precipitation. The species identified, although widely distributed, respond to a floristic pattern according to the vegetation types where the rock outcrops are located.
30

Taxonomy, biogeography and phylogeny of Cretaceous frog crabs (Crustacea, Decapoda, Brachyura) from the Neotropics

Luque, Javier 12 1900 (has links)
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.

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