Consulta: subjectFacets:"Species complex"
Registros recuperados: 18
Data/hora: 10/06/2024 12:04:00

Astyanax hastatus Myers, 1928 (Teleostei, Characidae): a new species complex within the genus Astyanax?
Provedor de dados: 74
Autores: Kavalco,Karine Frehner; Brandão,Karina de Oliveira; Pazza,Rubens; Almeida-Toledo,Lurdes Foresti de.
Four populations of Astyanax hastatus Myers 1928 from the Guapimirim River basin (Rio de Janeiro State) were analyzed and three distinct cytotypes identified. These cytotypes presented 2n = 50 chromosomes, with 4M+8SM+10ST+28A (Cytotype A), 8M+10SM+14ST+18A (Cytotype B), 6M+8SM+4ST+32A (Cytotype C) and scanty heterochromatin, mainly located throughout pericentromeric regions of several chromosomal pairs. No homologies with the As-51 satellite DNA were observed in the three cytotypes, although all of them presented multiple 18S rDNA sites, as detected by both silver nitrate staining and FISH (fluorescent in situ hybridization). The application of the term "species complex" in Astyanax is discussed from a cytotaxonomic viewpoint.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Astyanax hastatus; Molecular cytogenetics; Karyotypic evolution; Species complex.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572009000300009

Comparative karyotype analysis of populations in the Alstroemeria presliana Herbert (Alstroemeriaceae) complex in Chile
Provedor de dados: 74
Autores: Baeza,Carlos; Finot,Víctor L.; Ruiz,Eduardo.
Alstroemeria L., one of the most diverse genera of the Chilean flora and of high floricultural value, is represented by 35 species, most of them distributed between 28–38° S in the Mediterranean zone of Central Chile. There are 24 complex-forming taxa, of which 18 have conservation problems (8 are considered “endangered” and 10 as “vulnerable”). One of these complexes is Alstroemeria presliana Herb. with two subspecies: subsp. presliana and subsp. australis Bayer. Alstroemeria presliana grows in Chile and Argentina: subsp. presliana is distributed from Reserva Nacional Siete Tazas (35°27′ S, Region of Maule) to Antuco, (37°25′ S, Region of Bío-Bío), and is also found in Neuquén, Argentina; subsp. australis is endemic to the Cordillera of Nahuelbuta. A...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Alstroemeria; Asymmetry; Chile; Karyotype; Species complex.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572015000200199

Cytotaxonomic study of the Chilean endemic complex Alstroemeria magnifica Herb. (Alstroemeriaceae)
Provedor de dados: 74
Autores: Baeza,Carlos M.; Finot,Víctor; Ruiz,Eduardo; Carrasco,Pedro; Novoa,Patricio; Rosas,Marcelo; Toro-Núñez,Oscar.
Abstract Alstroemeria L. (Alstroemeriaceae) represents one of the most diverse genera of vascular plants in Chile. It contains approximately 54 taxa, 40 of which are endemic. The “complex” Alstroemeria magnifica is endemic to Chile, and it comprises four varieties: A. magnifica var. magenta, A. magnifica var. magnifica, A. magnifica var. sierrae, and A. magnifica var. tofoensis. It is distributed from Coquimbo to the Valparaíso Region. We analyzed karyotypes of 10 populations along its natural distribution. All the populations presented an asymmetric karyotype, with 2n = 16 chromosomes but with three different karyotypic formulae. Alstroemeria magnifica var. magnifica and A. magnifica var. sierrae presented the same karyotypic fomula, and A. magnifica var....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Alstroemeria; Karyotype; Species complex; Asymmetry; Chile.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572018000300434

Evolutionary Patterns in Pearl Oysters of the Genus Pinctada (Bivalvia: Pteriidae)
Provedor de dados: 5
Autores: Cunha, Regina L.; Blanc, Francoise; Bonhomme, Francois; Arnaud-haond, Sophie.
Pearl oysters belonging to the genus Pinctada (Bivalvia: Pteriidae) are widely distributed between the Indo-Pacific and western Atlantic. The existence of both widely distributed and more restricted species makes this group a suitable model to study diversification patterns and prevailing modes of speciation. Phylogenies of eight out of the 11 currently recognised Pinctada species using mitochondrial (cox1) and nuclear (18S rRNA) data yielded two monophyletic groups that correspond to shell size and presence/absence of hinge teeth. Character trace of these morphological characters onto the molecular phylogeny revealed a strong correlation. Pinctada margaritifera appears polyphyletic with specimens from Mauritius grouping in a different clade from others of...
Tipo: Text
Palavras-chave: Pinctada; Evolutionary patterns; Species complex; Allopatry; Biogeography.
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00035/14635/14015.pdf

Epitypification of Fusarium oxysporum – clearing the taxonomic chaos
Provedor de dados: 16
Autores: Lombard, L.; Sandoval-Denis, M.; Lamprecht, S.C.; Crous, P.W.
Fusarium oxysporum is the most economically important and commonly encountered species of Fusarium. This soil-borne fungus is known to harbour both pathogenic (plant, animal and human) and non-pathogenic strains. However, in its current concept F. oxysporum is a species complex consisting of numerous cryptic species. Identification and naming these cryptic species is complicated by multiple subspecific classification systems and the lack of living ex-type material to serve as basic reference point for phylogenetic inference. Therefore, to advance and stabilise the taxonomic position of F. oxysporum as a species and allow naming of the multiple cryptic species recognised in this species complex, an epitype is designated for F. oxysporum. Using multi-locus...
Tipo: Article / Letter to the editor
Palavras-chave: Cryptic species; Diversity; Human and plant pathogens; Species complex; Subspecific classification.
Ano: 2019
URL: http://www.repository.naturalis.nl/record/673170

Elucidating the Ramularia eucalypti species complex
Provedor de dados: 16
Autores: Videira, S.I.R.; Groenewald, J.Z.; Kolecka, A.; Haren, L. van; Boekhout, T.; Crous, P.W.
The genus Ramularia includes numerous phytopathogenic species, several of which are economically important. Ramularia eucalypti is currently the only species of this genus known to infect Eucalyptus by causing severe leaf-spotting symptoms on this host. However, several isolates identified as R. eucalypti based on morphology and on nrDNA sequence data of the ITS region have recently been isolated from other plant hosts, from environmental samples and also from human clinical specimens. Identification of closely related species based on morphology is often difficult and the ITS region has previously been shown to be unreliable for species level identification in several genera. In this study we aimed to resolve this species-complex by applying a polyphasic...
Tipo: Article / Letter to the editor
Palavras-chave: Mycosphaerellaceae; Plant pathogen; Species complex; Systematics.
Ano: 2015
URL: http://www.repository.naturalis.nl/record/560060

Phylogenetic reassessment of the Chaetomium globosum species complex
Provedor de dados: 16
Autores: Wang, X.W.; Lombard , L.; Groenewald, J.Z.; Li, J.; Videira, S.I.R.; Samson, R.A.; Liu, X.Z.; Crous, P.W.
Chaetomium globosum, the type species of the genus, is ubiquitous, occurring on a wide variety of substrates, in air and in marine environments. This species is recognised as a cellulolytic and/or endophytic fungus. It is also known as a source of secondary metabolites with various biological activities, having great potential in the agricultural, medicinal and industrial fields. On the negative side, C. globosum has been reported as an air contaminant causing adverse health effects and as causal agent of human fungal infections. However, the taxonomic status of C. globosum is still poorly understood. The contemporary species concept for this fungus includes a broadly defined morphological diversity as well as a large number of synonymies with limited...
Tipo: Article / Letter to the editor
Palavras-chave: DNA barcode; Epitypification; Multi-gene phylogeny; Species complex; Systematics.
Ano: 2016
URL: http://www.repository.naturalis.nl/record/607374

Studies in Asian Nervilia (Orchidaceae) VII: Nervilia kasiensis, a new Lao endemic
Provedor de dados: 16
Autores: Gale, S.W.; Phaxaysombath, T.
A new species belonging to the terrestrial orchid genus Nervilia is described from Kasi District, Vientiane Province, northern Laos. Referable to the widespread and species-rich N. adolphi/punctata alliance on account of its  solitary flower, slender white and violet-marked labellum and glabrous, angular leaf, N. kasiensis is morphologically most closely allied to N. muratana of southern China and northern Vietnam. As in that species, the flowering and leafing phases overlap, an unusual feature among members of the genus. The new species can be distinguished from N. muratana by its shorter inflorescence, its weakly spreading perianth with beige sepals, its narrower labellum with a central pubescent strip on the epichile, its arched column, and by its...
Tipo: Article / Letter to the editor
Palavras-chave: Hysteranthy; Laos; New species; Orchidaceae; Species complex.
Ano: 2017
URL: http://www.repository.naturalis.nl/record/622396

Het Dryopteris affinis-complex in Nederland
Provedor de dados: 16
Autores: Hovenkamp, P.; Hendrikx, B.; Roskam, H.; Winter, W. de.
With the help of flow-cytometric analysis of nuclear DNA content and morphology, we establish the presence in the Netherlands of two taxa of the Dryopteris affinis complex: diploid D. affinis subsp. affinis, triploid D. affinis subsp. borreri, and the hybrids D × complexa (tetraploid) and D. × critica (pentaploid).  Onderzoek aan kern-DNA gewicht en morfologie van recente vondsten van het Dryopteris affinis-complex wijst uit dat in Nederland twee taxa en twee hybrides met redelijke zekerheid zijn gevonden: dediploïde D. affinis subsp. affinis, de triploïde D. affinis subsp. borreri, en de hybriden D × complexa (tetraploïd) en D. × critica (pentaploïd). We analyseren een aantal onderscheidende kenmerken en maken de keuze om deze taxa te behandelen als...
Tipo: Article / Letter to the editor
Palavras-chave: Dryopteris affinis; Soortscomplex; Species complex; Uitbreiding; Range expansion; Genoomgrootte; Genome size; Cytotypes; Polyploidie; Polyploidy; Morfometrie; Morphometrics.
Ano: 2018
URL: http://www.repository.naturalis.nl/record/669050

Comparative cytogenetics of Astyanax (Teleostei: Characidae) from the upper Paraguay basin
Provedor de dados: 83
Autores: Teixeira,Thais K. S. S.; Venere,Paulo C.; Ferreira,Daniela C.; Mariotto,Sandra; Castro,Jonathan P.; Artoni,Roberto F.; Centofante,Liano.
ABSTRACT Astyanax is one of the most abundant and diverse taxa of fishes in the Neotropical region. In order to increase the amount of cytogenetic information for Astyanax as well as to exhibit data to subsidize future taxonomic studies, this work analyzed three species of Astyanax: two species are cryptic, and are here reported to live in syntopy (A. abramis and A. lacustris); the first karyotype description for A. pirapuan is also presented. Cytogenetic analyzes reveal a diploid number of 2n=50 chromosomes for three species, yet with differences in their karyotype morphology. The physical mapping of 18S rDNA showed up to thirteen sites in A. pirapuan and two in A. abramis and A. lacustris. The physical mapping of 5S rDNA has proven to be an effective...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cryptic species; Fish; Karyotype; Species complex.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252018000100214

Astyanax henseli, a new name for Tetragonopterus aeneus Hensel, 1870 from southern Brazil (Teleostei: Characiformes)
Provedor de dados: 83
Autores: Melo,Filipe A. G. de; Buckup,Paulo A.
Tetragonopoterus aeneus Hensel (1870) is removed from synonymy with Astyanax fasciatus (Cuvier, 1819), revalidated and redescribed as A. henseli to avoid homonymy. Astyanax henseli differs from A. fasciatus stricto sensu and other Astyanax species by the presence of two to four maxillary teeth, two vertically-elongated humeral spots, dentary tooth cusps positioned close to one another, and the slender form of the dentary teeth.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Taxonomy; Astyanax fasciatus; Species complex; Rio Jacuí; Fish; Freshwater.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252006000100003

DNA barcoding confirms the occurrence of Rhamdia branneri and Rhamdia voulezi (Siluriformes: Heptapteridae) in the Iguaçu River Basin
Provedor de dados: 83
Autores: Ribolli,Josiane; Scaranto,Bianca Maria; Shibatta,Oscar Akio; Bombardelli,Robie Allan; Zaniboni-Filho,Evoy.
ABSTRACT DNA barcoding is a widely utilized molecular-based identification of species and taxonomic resolutions. Until recently, Rhamdia voulezi and Rhamdia branneri were considered species synonyms of Rhamdia quelen; however, morphological and cytogenetic analyses have suggested the validity of distinct species. Due to the absence of molecular taxonomy of R. voulezi and R. branneri, the objective of this study was to test its validity through traditional DNA barcoding and the GMYC (General Mixed Yule Coalescent) COI-based analyses in 19 specimens from the Iguaçu River Basin. In both methodologies, three MOTUs (Molecular Operational Taxonomic Units) were identified based on the estimated optimum threshold (OT = 0.77). The average inter-MOTU distance (NJ,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Aquaculture; COI; Jundiá; MOTU; Species complex.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252017000100217

Molecular and cytogenetic analyses of cryptic species within the Synbranchus marmoratus Bloch, 1795 (Synbranchiformes: Synbranchidae) grouping: species delimitations, karyotypic evolution and intraspecific diversification
Provedor de dados: 83
Autores: Utsunomia,Ricardo; Pansonato-Alves,José C.; Costa-Silva,Guilherme J.; Mendonça,Fernando F.; Scacchetti,Priscilla C.; Oliveira,Claudio; Foresti,Fausto.
The fish species Synbranchus marmoratushas been reported to exist as a species complex due to high intraspecific karyotypic variability in spite of the difficulty or impossibility to distinguish them using morphological traits alone. The goal of this work was to use cytogenetic and molecular methods to determine the species delimitations and understand the karyoevolution ofS. marmoratususing samples collected from distinct Brazilian localities. Among the analyzed specimens, a large degree of cytogenetic variation related to diploid numbers and karyotype structure was observed, with karyotypes showing 2n=42, 44 and 46 chromosomes. In addition, using sequences of three mitochondrial genes, the phylogenetic relationships between every sample with a known...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chromosomal diversity; Fish cytogenetics; Karyotype evolution; Repetitive DNA; Species complex.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252014000400903

Revision of Bairdiella (Sciaenidae: Perciformes) from the western South Atlantic, with insights into its diversity and biogeography
Provedor de dados: 83
Autores: Marceniuk,Alexandre Pires; Molina,Eduardo Garcia; Caires,Rodrigo Antunes; Rotundo,Matheus Marcos; Wosiacki,Wolmar Benjamin; Oliveira,Claudio.
ABSTRACT The sciaenid genus Bairdiella comprises a group of relatively small fishes found in inshore waters and estuaries of the western Atlantic and eastern Pacific. Despite recent analyses of the phylogenetic relationships of Bairdiella, there has been no comprehensive revision of the alpha taxonomy of the species of the genus. Bairdiella ronchus from the western Atlantic, has a complex taxonomic history, with four junior synonyms recognized. Based on morphological and molecular evidence, this study indicates that B. ronchus represents a species complex. The species is therefore redescribed and its geographic range is redefined. Bairdiella veraecrucis, which is currently recognized as a junior synonym of B. ronchus, is revalidated, and a new species of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Biogeographic patterns; New species; Species complex; Taxonomy; Western Atlantic.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252019000100205

Cytogenetic and DNA barcoding reveals high divergence within the trahira, Hoplias malabaricus (Characiformes: Erythrinidae) from the lower Amazon River
Provedor de dados: 83
Autores: Marques,Diego Ferreira; Santos,Fabíola Araújo dos; Silva,Simoni Santos da; Sampaio,Iracilda; Rodrigues,Luís Reginaldo Ribeiro.
Molecular and cytogenetic data have provided evidence of cryptic speciation in the widespread South American trahira, Hoplias malabaricus. In the present study, karyotypes and DNA barcode sequences of specimens from seven populations inhabiting the lower Amazon River were analyzed in order to characterize the levels of genetic divergence within a single karyomorph. All the specimens presented karyotypes with 2n = 40 chromosomes (20m+20sm) that were consistent with the species' C karyomorph. The DNA barcodes revealed six haplogroups, with clear divergence between populations from Brazil and Argentina. The results support the species complex hypothesis and indicate that a single karyomorph of H. malabaricus may harbor more than one species
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Amazon basin; COI; Karyomorph; Species complex; Trahiras.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252013000200459

Morphometric analysis of the Brasiliorchis picta complex (Orchidaceae)
Provedor de dados: 88
Autores: Pinheiro,Fábio; Barros,Fábio de.
One of the largest genera of Orchidaceae in the Neotropics with about 450 species, Maxillaria presents several taxonomic uncertainties about its generic circumscription and the delimitation of species groups, mainly due to the large variability of some species. The present study aims at verifying the morphological variation and species delimitation in the Brasiliorchis picta complex, a recent new genus derived from Maxillaria, using morphometric multivariate analysis. A total of 340 specimens belonging to six species (B. chrysantha (Barb. Rodr.) R.B. Singer, S. Koehler &amp;amp; Carnevali, B. gracilis (Lodd.) R.B. Singer, S. Koehler &amp;amp; Carnevali, B. marginata (Lindl.) R.B. Singer, S. Koehler &amp;amp; Carnevali, B. picta (Hook.) R. Singer, S....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Morphometry; Multivariate analysis; Species complex; Taxonomy.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84042009000100003

Complexo Littorina ziczac (Gmelin) (Mollusca, Gastropoda, Caenogastropoda) no litoral fluminense: análise morfométrica, distribuição vertical e bioquímica
Provedor de dados: 104
Autores: Absalão,Ricardo Silva; Roberg,Renata Alves Pinheiro.
The Littorina ziczac (Gmelin, 1791) species complex was studied in Rio de Janeiro State, southeastern Brazil. The occurrence of three species was confirmed, through the analysis of penis morphology: L. ziczac (Gmelin, 1791), L. lineata d'Orbigny, 1841 and L. lineolata d'Orbigny, 1840. There is a correlation between the morphology of the penis and shell shape, thus it was possible to make a discrimination model based in conchologic data, with an efficiency of 75%. However, this model cannot be applied to others samples that weren't included in its formulation, due to phenotypic plasticity of the shell caused by biotic and abiotic factors. In the 9 areas studied L. lineolata was always the most abundam species. No vertical stratification in the distribution...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Littorina; Species complex; Vertical distribution; Biochemistiy; Rio de Janeiro; Brazil.
Ano: 1999
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81751999000200005

A new species of terrestrial planarian of the genus Notogynaphallia Ogren &amp;amp; Kawakatsu (Platyhelminthes, Tricladida, Terricola) from south Brazil and some comments on the genus
Provedor de dados: 104
Autores: Froehlich,Eudóxia Maria; Leal-Zanchet,Ana Maria.
A new species of Notogynaphallia Ogren &amp;amp; Kawakatsu, 1990, from Southern Brazil, is described. Notogynaphallia ceciliae sp. nov. has an elongated body with parallel margins and five dorsal dark longitudinal stripes on a yellowish ground. It possess branched efferent ducts, each branch opening separately into the anterior and median thirds of the long prostatic vesicle. Comparative commentaries on the most important characters of the external and internal morphology of the 23 species of the genus are also presented, so delimiting smaller inside groups.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Geoplaninae; Morphology; Species complex; Taxonomy.
Ano: 2003
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752003000400030