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Allozymatic divergence between border populations of two cryptic species of the Drosophila buzzatii cluster species (Diptera: Drosophilidae)

MATEUS, Rogrio R.; MACHADO, Luciana P. B.; MORAES, Evandro M.; SENE, Fabio M.
Fonte: PERGAMON-ELSEVIER SCIENCE LTD Publicador: PERGAMON-ELSEVIER SCIENCE LTD
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
66.38%
Drosophila antonietae and Drosophila gouveai are allopatric, cactophilic, cryptic and endemic of South America species, which aedeagus morphology is considered the main diagnostic character. In this work, single close populations from the edge distributions of each species, located in an ""introgressive corridor"", were analyzed regarding temporal isozenzymatic genetic variability. Isocitrate dehydrogenase (Idh) appeared as a diagnostic locus between D. antonieate and D. gouveai because each population was fixed for different alleles. Moreover, several polymorphic loci showed accentuated divergence in the allele frequency, as evidenced by Nei`s l(0.3188) and D (1.1432), and also by Reynolds` genetic distance and identity (1.3207 and 0.7331, respectively). Our results showed that, in spite of the very similar external morphology, related evolutionary histories, close distributions, and events of introgression in the studied area, these cryptic species have high allozymatic differentiation, and this is discussed here. (C) 2010 Elsevier Ltd. All rights reserved.; FAPESP[97/13822-4]; FAPESP[1998/1790-3]; FAPESP[98/00974-3]; CNPq; CAPES; FINEP; FAEPA; Universidade de São Paulo USP

Cryptic species in Iphisa elegans Gray, 1851 (Squamata: Gymnophthalmidae) revealed by hemipenial morphology and molecular data

Nunes, Pedro Murilo Sales; Fouquet, Antoine; Curcio, Felipe F.; Kok, Philippe J. R.; Rodrigues, Miguel Trefaut Urbano
Fonte: WILEY-BLACKWELL; HOBOKEN Publicador: WILEY-BLACKWELL; HOBOKEN
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
56.37%
Iphisa elegans Gray, 1851 is a ground-dwelling lizard widespread over Amazonia that displays a broadly conserved external morphology over its range. This wide geographical distribution and conservation of body form contrasts with the expected poor dispersal ability of the species, the tumultuous past of Amazonia, and the previously documented prevalence of cryptic species in widespread terrestrial organisms in this region. Here we investigate this homogeneity by examining hemipenial morphology and conducting phylogenetic analyses of mitochondrial (CYTB) and nuclear (C-MOS) DNA sequence data from 49 individuals sampled across Amazonia. We detected remarkable variation in hemipenial morphology within this species, with multiple cases of sympatric occurrence of distinct hemipenial morphotypes. Phylogenetic analyses revealed highly divergent lineages corroborating the patterns suggested by the hemipenial morphotypes, including co-occurrence of different lineages. The degrees of genetic and morphological distinctness, as well as instances of sympatry among mtDNA lineages/morphotypes without nuDNA allele sharing, suggest that I. elegans is a complex of cryptic species. An extensive and integrative taxonomic revision of the I. elegans complex throughout its wide geographical range is needed. (c) 2012 The Linnean Society of London...

Morphological, molecular and cross-breeding analysis of geographic populations of coconut-mite associated predatory mites identified as Neoseiulus baraki: evidence for cryptic species?

Sourassou, Nazer Famah; Hanna, Rachid; Zannou, Ignace; Breeuwer, Johannes A. J.; Moraes, Gilberto José de; Sabelis, Maurice W.
Fonte: SPRINGER; DORDRECHT Publicador: SPRINGER; DORDRECHT
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
56.19%
Surveys were conducted in Brazil, Benin and Tanzania to collect predatory mites as candidates for control of the coconut mite Aceria guerreronis Keifer, a serious pest of coconut fruits. At all locations surveyed, one of the most dominant predators on infested coconut fruits was identified as Neoseiulus baraki Athias-Henriot, based on morphological similarity with regard to taxonomically relevant characters. However, scrutiny of our own and published descriptions suggests that consistent morphological differences may exist between the Benin population and those from the other geographic origins. In this study, we combined three methods to assess whether these populations belong to one species or a few distinct, yet closely related species. First, multivariate analysis of 32 morphological characters showed that the Benin population differed from the other three populations. Second, DNA sequence analysis based on the mitochondrial cytochrome oxidase subunit I (COI) showed the same difference between these populations. Third, cross-breeding between populations was unsuccessful in all combinations. These data provide evidence for the existence of cryptic species. Subsequent morphological research showed that the Benin population can be distinguished from the others by a new character (not included in the multivariate analysis)...

Species delimitation, patterns of diversification and historical biogeography of the Neotropical frog genus Adenomera (Anura, Leptodactylidae)

Fouquet, Antoine; Cassini, Carla Santana; Haddad, Célio Fernando Baptista; Pech, Nicolas; Rodrigues, Miguel Trefaut Urbano
Fonte: John Wiley & Sons; Oxford Publicador: John Wiley & Sons; Oxford
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
56.25%
Aim For many taxa, inaccuracy of species boundaries and distributions hampers inferences about diversity and evolution. This is particularly true in the Neotropics where prevalence of cryptic species has often been demonstrated. The frog genus Adenomera is suspected to harbour many more species than the 16 currently recognized. These small terrestrial species occur in Amazonia, Atlantic Forest (AF), and in the open formations of the Dry Diagonal (DD: Chaco, Cerrado and Caatinga). This widespread and taxonomically complex taxon provides a good opportunity to (1) test species boundaries, and (2) investigate historical connectivity between Amazonia and the AF and associated patterns of diversification. Location Tropical South America east of the Andes. Methods We used molecular data (four loci) to estimate phylogenetic relationships among 320 Adenomera samples. These results were integrated with other lines of evidence to propose a conservative species delineation. We subsequently used an extended dataset (seven loci) and investigated ancestral area distributions, dispersal–vicariance events, and the temporal pattern of diversification within Adenomera. Results Our conservative delineation identified 31 Confirmed Candidate Species (four remaining unconfirmed) representing a 94% increase in species richness. The biogeographical analysis suggested an Amazonian origin of Adenomera with as many as three dispersals to the DD and one to the AF during the Miocene. These dispersals were associated with habitat shifts from forest towards open habitats. Main conclusions The DD played a major role in the history of Adenomera in limiting dispersal and favouring diversification of open-habitat lineages. Moreover...

Cryptic Diversity within Morphospecies of Testate Amoebae (Amoebozoa: Arcellinida) in New England Bogs and Fens

Oliveiro, Angela M.; Lahr, Daniel José Galafasse; Nguyen, Truc; Katz, Laura A.
Fonte: Elsevier GmbH; Jena Publicador: Elsevier GmbH; Jena
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
56.28%
Testate (shelled) amoebae are abundant and diverse in Sphagnum-rich areas of bogs and fens. Test morphology is standardly used to identify morphospecies as tests have varying shapes and compositions (e.g. siliceous, proteinaceous, agglutinated, or even calcareous). The recent application of molecular tools has revealed a greater complexity than morphology suggests, including multiple cryptic species. Here, we assess the biodiversity and relationships among eight morphospecies: Hyalosphenia elegans, Hyalosphenia papilio, Nebela carinata, Nebela flabellulum, Nebela militaris, Nebela tincta, Nebela tubulosa, and Quadrulella symmetrica using small subunit ribosomal DNA (SSU-rDNA). An SSU-rDNA phylogeny including 20 specimens from GenBank and 63 from this study reveals diversity within and among morphospecies and low resolution among some Nebela spp. Previous SSU-rDNA work on a limited sample of these species showed non-monophyly in the genus Hyalosphenia. Our analyses confirm this pattern and further suggest that other Nebela genera and morphospecies are not monophyletic. Moreover, inclusion of up to 24 specimens per species indicates non-monophyly of the morphospecies Hyalosphenia papilio and Hyalosphenia elegans. Our results suggest the morphological plasticity of testate amoebae across evolutionary time scales and that a combination of morphology and molecular analyses is needed to understand the biodiversity of these taxa.; The authors would like to thank Jessica R. Grant...

Phylogenetic analysis of PRP8 intein in Paracoccidioides brasiliensis species

Theodoro, Raquel C.; Bagagli, Eduardo; Oliveira, Claudio
Fonte: Academic Press Inc. Elsevier B.V. Publicador: Academic Press Inc. Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 1284-1291
ENG
Relevância na Pesquisa
56.22%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Processo FAPESP: 06/03597-4; Processo FAPESP: 07/01306-5; A recent species status investigation of the pathogenic fungus Paracoccidioides brasiliensis suggested the existence of three cryptic species. In the present study the sequences of the PRP8 intein from A brasiliensis isolates belonging to the three described genetic groups and two unidentified isolates were determined and analyzed in order to check their functionality and usefulness for species identification. All the isolates presented a full-length intein, although the Endonuclease domain seems to be inactive due to substitutions in the second essential aspartic acid residue. Phylogenetic analysis by Maximum-Parsimony, Maximum Likelihood, and Bayesian Analysis clearly separated the isolates from the three species and revealed a significant difference between the Pb01 isolate and the remaining ones. The Pb01 isolate does not belong to any of the groups previously described since it presented a high divergence level compared to the three different genetic groups, corroborating some previous studies that suggested this isolate represents a new species of Paracoccidioides. (C) 2008 Elsevier B.V. All rights reserved.

DNA barcode discovers two cryptic species and two geographical radiations in the invasive drosophilid Zaprionus indianus

Yassin, Amir; Capy, Pierre; Madi-Ravazzi, Lilian; Ogereau, David; David, Jean R.
Fonte: Blackwell Publishing Publicador: Blackwell Publishing
Tipo: Artigo de Revista Científica Formato: 491-501
ENG
Relevância na Pesquisa
56.33%
Comparing introduced to ancestral populations within a phylogeographical context is crucial in any study aiming to understand the ecological genetics of an invasive species. Zaprionus indianus is a cosmopolitan drosophilid that has recently succeeded to expand its geographical range upon three continents (Africa, Asia and the Americas). We studied the distribution of mitochondrial DNA (mtDNA) haplotypes for two genes (CO-I and CO-II) among 23 geographical populations. mtDNA revealed the presence of two well-supported phylogenetic lineages (phylads), with bootstrap value of 100%. Phylad I included three African populations, reinforcing the African-origin hypothesis of the species. Within phylad II, a distinct phylogeographical pattern was discovered: Atlantic populations (from the Americas and Madeira) were closer to the ancestral African populations than to Eastern ones (from Madagascar, Middle East and India). This means that during its passage from endemism to cosmopolitanism, Z. indianus exhibited two independent radiations, the older (the Eastern) to the East, and the younger (the Atlantic) to the West. Discriminant function analysis using 13 morphometrical characters was also able to discriminate between the two molecular phylads (93.34 +/- 1.67%)...

PRP8 intein in cryptic species of Histoplasma capsulatum: Evolution and phylogeny

Theodoro, Raquel Cordeiro; Scheel, Christina M.; Brandt, Mary E.; Kasuga, Takao; Bagagli, Eduardo
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 174-182
ENG
Relevância na Pesquisa
56.37%
The PRP8 intein is the most widespread intein among the Kingdom Fungi. This genetic element occurs within the prp8 gene, and is transcribed and translated simultaneously with the gene. After translation, the intein excises itself from the Prp8 protein by an autocatalytic splicing reaction, subsequently joining the N and C terminals of the host protein, which retains its functional conformation. Besides the splicing domain, some PRP8 inteins also have a homing endonuclease (HE) domain which, if functional, makes the intein a mobile element capable of becoming fixed in a population. This work aimed to study (1) The occurrence of this intein in Histoplasma capsulatum isolates (n=. 99) belonging to different cryptic species collected in diverse geographical locations, and (2) The functionality of the endonuclease domains of H. capsulatum PRP8 inteins and their phylogenetic relationship among the cryptic species. Our results suggest that the PRP8 intein is fixed in H. capsulatum populations and that an admixture or a probable ancestral polymorphism of the PRP8 intein sequences is responsible for the apparent paraphyletic pattern of the LAmA clade which, in the intein phylogeny, also encompasses sequences from LAmB isolates. The PRP8 intein sequences clearly separate the different cryptic species...

Cryptic species of Paracoccidioides brasiliensis: impact on paracoccidioidomycosis immunodiagnosis

Machado, Gabriel Capella; Moris, Daniela Vanessa; Arantes, Thales Domingos; Silva, Luciane Regina Franciscone; Theodoro, Raquel Cordeiro; Mendes, Rinaldo Poncio; Vicentini, Adriana Pardini; Bagagli, Eduardo
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: 637-643
ENG
Relevância na Pesquisa
66.28%
We aimed to evaluate whether the occurrence of cryptic species of Paracoccidioides brasiliensis, S1, PS2, PS3 and Paracoccidioides lutzii, has implications in the immunodiagnosis of paracoccidioidomycosis (PCM). Small quantities of the antigen gp43 were found in culture filtrates of P. lutzii strains and this molecule appeared to be more variable within P. lutzii because the synonymous-nonsynonymous mutation rate was lower, indicating an evolutionary process different from that of the remaining genotypes. The production of gp43 also varied between isolates belonging to the same species, indicating that speciation events are important, but not sufficient to fully explain the diversity in the production of this antigen. The culture filtrate antigen AgEpm83, which was obtained from a PS3 isolate, showed large quantities of gp43 and reactivity by immunodiffusion assays, similar to the standard antigen (AgB-339) from an S1 isolate. Furthermore, AgEpm83 was capable of serologically differentiating five serum samples from patients from the Botucatu and Jundiaí regions. These patients had confirmed PCM but, were non-reactive to the standard antigen, thus demonstrating an alternative for serological diagnosis in regions in which S1 and PS2 occur. We also emphasise that it is not advisable to use a single antigen preparation to diagnose PCM...

Species delimitation, patterns of diversification and historical biogeography of the Neotropical frog genus Adenomera (Anura, Leptodactylidae)

Fouquet, Antoine; Cassini, Carla Santana; Baptista Haddad, Celio Fernando; Pech, Nicolas; Rodrigues, Miguel Trefaut
Fonte: Wiley-Blackwell Publicador: Wiley-Blackwell
Tipo: Artigo de Revista Científica Formato: 855-870
ENG
Relevância na Pesquisa
56.25%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Processo FAPESP: 07/57067-9; Processo FAPESP: 10/51606-8; AimFor many taxa, inaccuracy of species boundaries and distributions hampers inferences about diversity and evolution. This is particularly true in the Neotropics where prevalence of cryptic species has often been demonstrated. The frog genus Adenomera is suspected to harbour many more species than the 16 currently recognized. These small terrestrial species occur in Amazonia, Atlantic Forest (AF), and in the open formations of the Dry Diagonal (DD: Chaco, Cerrado and Caatinga). This widespread and taxonomically complex taxon provides a good opportunity to (1) test species boundaries, and (2) investigate historical connectivity between Amazonia and the AF and associated patterns of diversification.LocationTropical South America east of the Andes.MethodsWe used molecular data (four loci) to estimate phylogenetic relationships among 320 Adenomera samples. These results were integrated with other lines of evidence to propose a conservative species delineation. We subsequently used an extended dataset (seven loci) and investigated ancestral area distributions...

Three new cryptic species of the lamprey genus Lampetra Bonnaterre, 1788 (Petromyzontiformes: Petromyzontidae) from the Iberian Peninsula.

Mateus, Catarina; Alves, Judite; Quintella, Bernardo; Almeida, Pedro R.
Fonte: Netherlands Centre for Biodiversity Naturalis Publicador: Netherlands Centre for Biodiversity Naturalis
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
66.3%
The Iberian Peninsula is a repository for biodiversity, presenting high levels of endemism in both plants and animals. In this peninsular region, brook lampreys confined to small, isolated river basins evolved in allopatry giving rise to evolutionary lineages, as revealed by mitochondrial DNA markers. For a better understanding of the taxonomic status and relationships of Iberian populations of the genus Lampetra, we combined previous data from genetics and morphological analysis (assessed here), and describe three new species of the lamprey genus Lampetra Bonnaterre, 1788 in Portugal. In this region L. planeri actually represent a complex of cryptic species, each having smaller geographic ranges than L. planeri, and consequently, greater vulnerability to extinction. The description of Lampetra alavariensis sp. nov. is based on 36 specimens collected on Ribeira de Mangas, a tributary of river Esmoriz, in Northern Portugal. Lampetra auremensis sp. nov. is described on the basis of 31 specimens collected on Ribeira do Olival, a small tributary of river Nabão (Tagus basin). Finally, Lampetra lusitanica sp. nov. is described based on 38 specimens from Ribeira da Marateca, Sado river basin, the southernmost distribution of the genus Lampetra. The recognition of these new species will contribute to the conservation of these already imperilled taxa and will help prevent the extinction of three important evolutionary lineages.

Molecular divergence in the timeless and cpr genes among three sympatric cryptic species of the Anopheles triannulatus complex

Silva-do-Nascimento,Teresa Fernandes; Pitaluga,Luisa Damazio Rona; Peixoto,Alexandre Afranio; Lourenço-de-Oliveira,Ricardo
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2011 EN
Relevância na Pesquisa
56.22%
Anopheles triannulatus s.l. is a malaria vector with a wide geographic distribution, ranging from Argentina-Nicaragua and Trinidad. Here we analysed sequences of two genes, timeless and cpr, to assess the genetic variability and divergence among three sympatric cryptic species of this complex from Salobra, central-western Brazil. The timeless gene sequences did not conclusively differentiate Anopheles halophylus and An. triannulatus species "C". However, a partial separation has been observed between these species and An. triannulatus s.s. Importantly, the analysis of the cpr gene sequences revealed fixed differences, no shared polymorphisms and considerable genetic differentiation among the three species of the An. triannulatus complex. The results confirm that An. triannulatus s.s., An. halophylus and An. triannulatus species C are distinct taxa, with the latter two likely representing a more recent speciation event.

Cryptic species of Paracoccidioides brasiliensis: impact on paracoccidioidomycosis immunodiagnosis

Machado,Gabriel Capella; Moris,Daniela Vanessa; Arantes,Thales Domingos; Silva,Luciane Regina Franciscone; Theodoro,Raquel Cordeiro; Mendes,Rinaldo Pôncio; Vicentini,Adriana Pardini; Bagagli,Eduardo
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2013 EN
Relevância na Pesquisa
66.28%
We aimed to evaluate whether the occurrence of cryptic species of Paracoccidioides brasiliensis, S1, PS2, PS3 and Paracoccidioides lutzii, has implications in the immunodiagnosis of paracoccidioidomycosis (PCM). Small quantities of the antigen gp43 were found in culture filtrates of P. lutzii strains and this molecule appeared to be more variable within P. lutzii because the synonymous-nonsynonymous mutation rate was lower, indicating an evolutionary process different from that of the remaining genotypes. The production of gp43 also varied between isolates belonging to the same species, indicating that speciation events are important, but not sufficient to fully explain the diversity in the production of this antigen. The culture filtrate antigen AgEpm83, which was obtained from a PS3 isolate, showed large quantities of gp43 and reactivity by immunodiffusion assays, similar to the standard antigen (AgB-339) from an S1 isolate. Furthermore, AgEpm83 was capable of serologically differentiating five serum samples from patients from the Botucatu and Jundiaí regions. These patients had confirmed PCM but, were non-reactive to the standard antigen, thus demonstrating an alternative for serological diagnosis in regions in which S1 and PS2 occur. We also emphasise that it is not advisable to use a single antigen preparation to diagnose PCM...

Cryptic species and genetic structure in Didemnum granulatum Tokioka, 1954 (Tunicata: Ascidiacea) from the southern Brazilian coast

Bouzon,JL; Vargas,SM; Oliveira Neto,JF; Stoco,PH; Brandini,FP
Fonte: Instituto Internacional de Ecologia Publicador: Instituto Internacional de Ecologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/11/2014 EN
Relevância na Pesquisa
66.38%
Didemnum granulatum is a colonial fouling ascidian that lives in subtidal substrates, worldwide. It exhibits two morphotypes, orange and beige. In this study, we verified if the color morphotypes and/or the spatial distribution of specimens in different islands might be associated to patterns of genetic structure of a single species, or if they represent distinct cryptic species. Specimens were collected in four islands, along the coast of the Santa Catarina state. A segment of 490 bp from the mitochondrial gene cytochrome c oxidase subunit 1 (COI) was amplified from 45 samples. Twenty-one haplotypes were identified. The total haplotype diversity (0.912) and the total nucleotide diversity (0.044) were high. The global Fst of the populations analyzed was 0.97, with most of the variation occurring between orange and beige groups (82.19%). The variation found between populations within groups was 15.37%, and 2.45% within populations. Haplotype networks and the neighbor-joining tree showed clear genetic divergence between individuals of distinct colors, and between the islands. These evidences strongly support the presence of a complex of two cryptic species for D. granulatum occupying the studied area. Both species were also highly genetically structured between islands...

Phylogenetic relationships, species limits, and host specificity of gall-forming Fergusonina flies (Diptera : Fergusoninidae) feeding on Melaleuca (Myrtaceae)

Scheffer, S.; Giblin-Davis, R.; Taylor, G.; Davies, K.; Purcell, M.; Lewis, M.; Goolsby, J.; Center, T.
Fonte: Entomol Soc Amer Publicador: Entomol Soc Amer
Tipo: Artigo de Revista Científica
Publicado em //2004 EN
Relevância na Pesquisa
56.32%
Phylogenetic analysis of recently described gall-forming Fergusonina Malloch flies was performed using DNA sequence data from the mitochondrial cytochrome oxidase I gene. Fifty-three flies reared from nine species of Melaleuca L. were sequenced. Species boundaries delimited by mitochondrial data confirm recent morphological investigation with one exception. Fergusonina turneri Taylor, believed to feed on both Melaleuca quinquenervia (Cav.) S. T. Blake and Melaleuca fluviatilis Barlow, seems to be comprised of two cryptic species, each specialized on one of the two hosts. Because F. turneri is under consideration as a potential biological control agent for invasive M. quinquenervia in the Florida Everglades, understanding cryptic variation and the degree of dietary specialization of this species is critical.; Copyright © 2004 Entomological Society of America

Divergent Molecular Lineages and Not-So-Cryptic Species: The First Descriptions of Stygobitic Chiltoniid Amphipods (Talitroidea: Chiltoniidae) from Western Australia

King, R.; Bradford, T.; Austin, A.; Humphreys, W.; Cooper, S.
Fonte: Crustacean Soc Publicador: Crustacean Soc
Tipo: Artigo de Revista Científica
Publicado em //2012 EN
Relevância na Pesquisa
66.38%
The Australian stygofauna comprises a unique and diverse assemblage of invertebrates, of which the amphipod crustaceans are a dominant but poorly described element. Recent exploration of the Western Australian stygofauna, in particular the Yilgarn region of central Western Australia, has shown evidence of great species diversity, with numerous individual calcrete aquifers found to contain unique assemblages of invertebrate species. A recent fine-scale biodiversity initiative, using COI barcoding, of a single calcrete aquifer (Sturt Meadows) in the Yilgarn region reported the presence of three divergent and morphologically cryptic stygobitic lineages of amphipods from Chiltoniidae, which represent undescribed taxa. This paper details the subsequent systematic analysis of these COI lineages and presents a broader phylogeny and detailed morphological analyses of the lineages. The report of cryptic species was not supported upon morphological examination and three new species from three new genera (Scutachiltonia n. gen., Stygochiltonia n. gen., and Yilgarniella n. gen.) are described from the Sturt Meadows calcrete aquifer. The three genera do not form a monophyletic group and are instead believed to have evolved from separate colonisation events from distinct ancestors rather than from speciation events within the aquifer. This work contributes to a broader research initiative...

Cryptic species and phylogeographical structure in the tree Cedrela odorata L. throughout the Neotropics

Cavers, S.; Telford, A.; Cruz, F.; Castaneda, A.; Valencia, R.; Navarro, C.; Buonamici, A.; Lowe, A.; Vendramin, G.
Fonte: Blackwell Science Ltd Publicador: Blackwell Science Ltd
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
Relevância na Pesquisa
66.4%
AIM The origins of much Neotropical biodiversity remain a topic of debate, with both palaeogeographical and more recent climatic drivers playing a role in diversification both among and within species. Here we use a combination of molecular data to assess genetic variation within and among species in the Neotropical tree genus Cedrela, with a focus on Cedrela odorata, to test hypotheses on the drivers of diversification, to place known ecotypic variation in context and to detect intraspecific phylogeographical structure. LOCATION Central and South America, Cuba, Cayman Islands, Trinidad and Guadeloupe. METHODS Samples were collected from the field, existing collections and herbaria from across the geographical range, including a total of 528 individuals from 72 sites. A phylogenetic framework was constructed using internal transcribed spacer (ITS) sequence data (intergenic spacers plus flanking 18S and 26S regions), and genetic structure was analysed using a combination of chloroplast DNA sequences (trnC–ycf6, trnH–psbA) and chloroplast and nuclear microsatellite (single sequence repeat, SSR) loci. Phylogenetic reconstruction was undertaken using a combination of Bayesian and parsimony-based approaches; divergence times were estimated for major nodes. Geographical structure in chloroplast SSR data was analysed using SAMOVA...

Ancient drainages divide cryptic species in Australia's arid zone: morphological and multi-gene evidence for four new species of Beaked Geckos (Rhynchoedura)

Pepper, M.; Doughty, P.; Hutchinson, M.; Keogh, J.
Fonte: Academic Press Inc Elsevier Science Publicador: Academic Press Inc Elsevier Science
Tipo: Artigo de Revista Científica
Publicado em //2011 EN
Relevância na Pesquisa
66.34%
Deserts and other arid zones remain among the least studied biomes on Earth. Emerging genetic patterns of arid-distributed biota suggest a strong link between diversification history and both the onset of aridification and more recent cycles of severe aridification. A previous study based on 1 kb of mtDNA of the monotypic gecko genus Rhynchoedura identified five allopatric clades across the vast Australian arid zone. We supplemented this data with 2.2kb from three nuclear loci and additional mtDNA sequences. Phylogenetic relationships estimated from the mtDNA data with ML and Bayesian methods were largely concordant with relationships estimated with the nDNA data only, and mtDNA and nDNA data combined. These analyses, and coalescent-based species-tree inference methods implemented with (∗)BEAST, largely resolve the relationships among them. We also carried out an examination of 19 morphological characters for 268 museum specimens from across Australia, including all 197 animals for which we sequenced mtDNA. The mtDNA clades differ subtly in a number of morphological features, and we describe three of them as new species, raise a fourth from synonymy, and redescribe it and the type species, Rhynchoedura ornata. We also describe a morphologically distinctive new species from Queensland based on very few specimens. The distribution of arid zone clades across what is now relatively homogeneous sand deserts seems to be related to a topographic divide between the western uplands and eastern lowlands...

DNA barcoding of stygofauna uncovers cryptic amphipod diversity in a calcrete aquifer in Western Australia's arid zone

Bradford, T.; Adams, M.; Humphreys, W.; Austin, A.; Cooper, J.
Fonte: Blackwell Publishing Ltd Publicador: Blackwell Publishing Ltd
Tipo: Artigo de Revista Científica
Publicado em //2010 EN
Relevância na Pesquisa
56.28%
The arid Yilgarn region of Western Australia contains numerous subterranean calcrete aquifers with unique assemblages of obligate groundwater invertebrates (stygofauna). We aimed to establish a DNA barcoding framework for the macro-invertebrates present in a single calcrete, as a basis for future assessment of biodiversity of the Yilgarn calcretes and for investigating food webs. Intense sampling of a bore field grid in the Sturt Meadows calcrete was undertaken to obtain representatives of the entire macro-invertebrate ecosystem. A 623-bp fragment of the mitochondrial cytochrome c oxidase 1 (COI) gene was used to provide DNA barcodes for stygobiont macro-invertebrates plus terrestrial organisms that are found in the calcrete. Phylogenetic analyses revealed the existence of 12 divergent monophyletic groups of haplotypes. Subterranean amphipods (Chiltoniidae) showed three groups of COI haplotypes with sequence divergences between them of >11%. Allozyme analyses found a large number of fixed allelic differences between these three amphipod groups, indicating that there are three morphologically cryptic species within the Sturt Meadows calcrete. Unlike the sister triplet of dytiscid beetles present, the amphipods are not sister clades and are more closely related to other Yilgarn and non-Yilgarn amphipods than to each other. Our results show that the aquifer contains at least 12 macro-invertebrate species and DNA barcoding provides a useful means for discriminating species in this system.; T. Bradford...

Morphology, physiology, molecular phylogeny and sexual compatibility of the cryptic Pseudo-nitzschia delicatissima complex (Bacillariophyta), including the description of P. arenysensis sp. nov.

Quijano-Scheggia, Sonia
Fonte: Wiley-Blackwell Publicador: Wiley-Blackwell
Tipo: Artículo Formato: 8985 bytes; application/pdf
ENG
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18 pages, 34 figures, 5 tables; Several strains of Pseudo-nitzschia delicatissima were isolated from the northwestern Mediterranean Sea and compared using light and electron microscopy, phylogenetic analyses of internal transcribed spacer rDNA, together with studies of their mating system, estimations of growth rates and reduction in cell size with time. Morphological and phylogenetic analyses identified all strains as Pseudo-nitzschia delicatissima, but in the phylogenetic analyses they fell into two genetically distinct clades. Studies of fine structural morphological characteristics by electron microscopy did not allow discrimination of the two clades. Mating experiments showed successful sexualisation among strains of clade B/1; whereas, mating attempts in clade A/2 and between clade A/2 and clade B/1 were unsuccessful under the examined laboratory conditions. The morphological characteristics of the daughter generations F1 and F2 were analyzed and abnormalities in the F2 generation described. We describe for the first time the rapid size reduction in the F2 generation. Culture studies showed physiological differences between the two clades; strains from clade A/2 showed a tendency for higher growth rates and slower reduction in cell size than strains from clade B/1. Morphological and phylogenetic studies comparing strains from different parts of the world showed P. delicatissima as a cryptic species complex comprising at least two different genotypes...