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1.
Knowledge of the evolutionary processes that shaped a biota is important for both academic and conservation purposes. The objective of the present study is to analyse the mitochondrial genetic variation of Xiphorhynchus fuscus (Aves: Dendrocolaptidae) from the southern Atlantic forest in Brazil and Argentina, and to discuss whether the results support different hypotheses regarding the local intraspecific diversification of this species . We sequenced 575 bp of the control region of 114 specimens collected in the Brazilian states of Bahia, Minas Gerais, Rio de Janeiro, São Paulo, Paraná, and Santa Catarina, and in the province of Misiones in Argentina. We studied the population genetic structure with analysis of molecular variance and the demographic history with multiple regression analysis, coalescence simulations, and demographic tests. Xiphorhynchus fuscus presented a significant population genetic structure (Φst = 0.57). Three mitochondrial lineages were described, one associated with Xiphorhynchus fuscus tenuirostris and the others with Xiphorhynchus fuscus fuscus. The data did not support the primary influence of geographical barriers or rivers in the intraspecific diversification of X. fuscus in the southern Atlantic forest. Instead, the data supported the influence of isolation by geographical distance, recent vicariance events, and demographic expansions apparently related to Pleistocene and Holocene forest dynamics.  © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 91 , 73–84.  相似文献   

2.
A new species, Achetaria latifolia V.C.Souza, is described and illustrated. It is characterized by its broadly ovate leaves, indument of stems and leaves of noncapitate hairs, and pubescent capsule. Achetaria latifolia is known only in the coastal dune-area of Cabo Frio region, Rio de Janeiro State, Brazil.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 73–75.  相似文献   

3.
The northernmost occurrence of Bassanago albescens in the western Atlantic Ocean (off the coast of Rio de Janeiro, Brazil) is presented and compared with the available data on this species. Specimens formerly identified as Rhynchoconger guppyi from off the southern Brazilian coast are regarded as B. albescens.  相似文献   

4.
A new species, Eugenia marambaiensis M.C.Souza & M.P.Morim, is described and illustrated. It is characterized by having large translucent gland dots densely distributed on the leaves, with a caudate apex and slightly wavy margins and a glabrous raceme, with only two flowers. Eugenia marambaiensis was only found in the locality of Restinga da Marambaia, Rio de Janeiro, Brazil. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 306–308.  相似文献   

5.
A new genus and species of a short limbed and slightly elongate gymnophthalmid lizard is described from the Atlantic rain forests of north-eastern Brazil. The new genus is also characterized by short and stout pentadactyl limbs, presence of prefrontals, absence of frontoparietals, distinctive ear opening and eyelid, two pairs of genials, a distinct collar, smooth, quadrangular, dorsal scales, quadrangular ventrals, fused postfrontal and postorbital bones, and two pairs of sternal ribs. The geographical distribution of the new taxon extends from the state of Rio Grande do Norte to the northern bank of the Rio São Francisco in the state of Alagoas. All specimens were obtained in leaf litter, an observation which agrees with the fossorial habits suggested by the body shape and massive aspect of the head of this species. A phylogenetic analysis based on external morphology, osteology, and molecular data recovered the new lizard as the sister genus to Anotosaura , and Colobosauroides as the sister group to these two.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 144 , 543−557.  相似文献   

6.
The Neotropical characid fishes of the genus Chalceus Cuvier, 1817, are reviewed. In total, five species are recognized (including three new species). Chalceus epakros sp. nov. is the most widespread geographically, occurring in many rivers of the Amazon basin, the Río Orinoco and in the Essequibo River drainage in Guyana. Chalceus guaporensis sp. nov. is restricted to the upper Rio Madeira, Rio Guaporé and Río Madre de Dios, of Brazil, Bolivia and Peru, respectively. Chalceus spilogyros sp. nov. occurs only in the Rio Trombetas, lower Rio Tapajós and lower Rio Madeira drainages. Chalceus macrolepidotus Cuvier occurs in the Rio Negro drainage, middle and lower Río Orinoco basin and in the rivers of the Atlantic slopes of the Guianas, and Chalceus erythrurus Cope in the Rio Amazonas and Rio Solimões to Río Ucayali drainage in Peru. Chalceus ararapeera Cuvier & Valenciennes and Creagrutus pellegrini Puyo are considered synonyms of C. macrolepidotus , and Pellegrinina heterolepis Fowler is placed into the synonymy of C. erythrurus . Characters pertaining to the monophyly of Chalceus are discussed and a key to species is presented.  © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 140 , 103−135.  相似文献   

7.
A new subfamily, Delturinae, is described to accommodate the loricariid catfish genera Delturus Egenmann & Eigenmann, 1889 and Hemipsilichthys Eigenmann & Eigenmann, 1889, a clade recently demonstrated to be the sister group of all remaining loricariids except Lithogenes . The genus Hemipsilichthys is restricted to three species, H. gobio (Lütken, 1874), its sister species H. papillatus Pereira et al ., 2000, and H. nimius Pereira et al ., 2003. Relationships among species of Delturus were not resolved and a new species, D. brevis , is described from the Rio Jequitinhonha basin in eastern Brazil. The geographical distribution of Delturinae, exclusively on the south-eastern Brazilian Shield, indicates that south-eastern Brazil acts as either a refugium for basal loricariid taxa or a point of origin for the Loricariidae. Lectotypes are designated for D. parahybae Eigenmann & Eigenmann, 1889 and Plecostomus angulicauda Steindachner, 1877. Keys are presented for subfamilies of Loricariidae and for genera and species of Delturinae. Diagnoses are provided for all delturine clades and species.  © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society , 2006, 147 , 277–299.  相似文献   

8.
9.
Until recently, the rhynchonelliform (articulated) brachiopod fauna from the Brazilian continental shelf (western South Atlantic) was represented only by the endemic species Bouchardia rosea (Mawe), reported from coastal waters of the states of São Paulo and Rio de Janeiro. The present study, based on samples from coastal (<30 m), shelf, and continental slope waters (99–485 m), documents the South Atlantic brachiopod fauna and shows that this fauna is more widespread, diverse, and cosmopolitan than previously thought. Based on a total of 16,177 specimens, the following brachiopods have been identified: Bouchardia rosea (Family Bouchardiidae), Platidia anomioides (Family Platidiidae), Argyrotheca cf. cuneata (Family Megathyrididae), and Terebratulina sp. (Family Cancellothyrididae). In coastal settings, the fauna is overwhelmingly dominated by Bouchardia rosea . Rare juvenile (<2 mm) specimens of Argyrotheca cf. cuneata were also found at two shallow-water sites. In shelf settings (100–200 m), the fauna is more diverse and includes Bouchardia rosea , Terebratulina sp., Argyrotheca cf. cuneata , and Platidia anomioides . Notably, Bouchardia rosea was found in waters as deep as 485 m, extending the known bathymetric range of this genus. Also, the record of this brachiopod in waters of the state of Paraná is the southernmost known occurrence of this species. The genera Platidia and Terebratulina are documented here for the first time for the western South Atlantic. The Brazilian brachiopod fauna shares similarities with those from the Atlantic and Indian shelves of southern Africa, and from the Antarctic, Caribbean and Mediterranean waters. The present-day brachiopods of the western South Atlantic are much more cosmopolitan than previously thought and their Cenozoic palaeobiogeographic history has to be reconsidered from that perspective.  相似文献   

10.
Atlantic Forest mammals are still poorly known and very few localities have been properly surveyed and/or studied. Protected reserves are of paramount importance for the conservation of native flora and fauna. Hereby we provide a survey of mammals captured and/or observed in Poço das Antas Biological Reserve, the largest lowland Atlantic Forest reserve in Rio de Janeiro state, southeastern Brazil. A total of 77 species were recorded, several of them endemics and/or listed as threatened either by IUCN's Red List, by the Brazilian Red List or by the regional Red List of Rio de Janeiro State. Mammals are threatened in several ways in this area: (1) habitat loss and fragmentation, (2) road mortality, (3) fires, (4) poaching, (5) cattle grazing, (6) pollution, (7) exotic species, and (8) feral populations of dogs Canis familiaris and cats Felis catus. Despite all threats, this is an important site for biodiversity conservation and scientific research. Better management and more investment would surely improve its effectiveness in protecting Atlantic Forest mammals.  相似文献   

11.
Triplectides itatiaia sp. nov. is described from specimens collected on the Itatiaia massif, Mantiqueira mountain range, Rio de Janeiro state, Brazil. The new species can be distinguished by the presence of hind wing fork I petiolate, the long dorsal excision of segment X and the flat, apically rounded mesal lobes. Female and immature stages are unknown. A key to the Brazilian species in the genus is provided.  相似文献   

12.
《Journal of bryology》2013,35(1):9-22
Abstract

This work analyzes the phytogeographic patterns of the liverwort flora of the Atlantic Forest of the Rio de Janeiro State, south-eastern Brazil. The analysis was based on inventories made in fragments of Atlantic Forest in the state, collections from the RB herbarium, and information from the checklist and database of the bryoflora of Rio de Janeiro. The phytogeographic pattern for each taxon was characterized based on its current distribution. Three hundred and sixty liverwort taxa are recognized for Rio de Janeiro. The liverwort flora varies along an altitudinal gradient within the Atlantic Forest, with the montane belt having the greatest species richness (238), the highest number of exclusive taxa (63) and the greatest number of endemic species (23). The predominant phytogeographic element is of neotropical species (49%), followed by disjunct liverworts (18%). Forty-one taxa (11%) are endemic to the country, of which 34 are restricted to the Atlantic Forest. In the lowland and submontane formations species are wide-ranging, whereas the montane and upper montane formations are characterized by endemic species or those disjunct with the Andes. The liverwort flora emphasizes the importance of the fragments of Atlantic Forest in Rio de Janeiro as a centre of diversity and endemism, supporting 50% of the total liverwort species known in Brazil, 72% of those recorded from Atlantic Forest and 55% of the endemic species of the country. Species with an Afro-American and Andean disjunction make up a characteristic part of the liverwort flora, probably reflecting the effects of long-distance dispersal by air currents, migration over land before the breakup of the continents and climatic similarities between the high-altitude grasslands and the northern Andes.  相似文献   

13.
Polymorphism studies concerning HVI and HVII regions of mitochondrial DNA (mtDNA) have improved the understanding of the admixture genetic process related to the occupation of the continents by human population groups. We have analyzed the mtDNA lineages of 190 healthy and maternally unrelated individuals born in the metropolitan region of the Rio de Janeiro city, the capital of the State of Rio de Janeiro, southeastern Brazil. The data showing that 57.9, 25.3 and 16.8 % of the matrilineages found in Rio de Janeiro come from African, Amerindian and European population groups. They are, respectively, in close agreement with historical records which indicate that the admixture population of Brazil is the resulting of interethnic asymmetry crosses between individuals from those population groups. The high proportion of African mtDNA lineages in the population of Rio de Janeiro is in accordance with studies related to other Brazilian states.  相似文献   

14.
Shell colour polymorphism was examined in a population of the polyplacophoran Ischnochiton striolatus (Gray, 1828) living on intertidal rocks in Búzios, Rio de Janeiro State, Brazil. Nine shell colours were identified: green (most common), grey, pink, cream, brown, orange, white, black and purple. The species habitat was also examined using three rock characteristics: volume; turnover frequency, caused by hydrodynamic disturbance; and chromatic composition. Chitons were most frequently encountered on the undersides of rocks of intermediate volume which experienced medium-intensity hydrodynamic disturbance, and which harboured a chromatically rich biotic community. These findings were in agreement with the Intermediate Disturbance Hypothesis. As chitons depend on the biotic community on rocks for food and shelter, a greater variety of colours could increase the chances of camouflage of the morphs against the background, favouring crypsis. It is likely that the frequency at which intermediate-volume rocks are overturned − thus exposing the chitons on them to light − would be sufficient for visual predators to act as selective agents.  © 2005 The Linnean Society of London, Biological Journal of the Linnean Society , 2005, 85 , 543–548.  相似文献   

15.
Extensive population structuring is known to occur in Anopheles darlingi , the primary malaria vector of the Neotropics. We analysed the phylogeographic structure of the species using the mitochondrial cytochrome oxidase I marker. Diversity is divided into six main population groups in South America: Colombia, central Amazonia, southern Brazil, south-eastern Brazil, and two groups in north-east Brazil. The ancestral distribution of the taxon is hypothesized to be central Amazonia, and there is evidence of expansion from this region during the late Pleistocene. The expansion was not a homogeneous front, however, with at least four subgroups being formed due to geographic barriers. As the species spread, populations became isolated from each other by the Amazon River and the coastal mountain ranges of south-eastern Brazil and the Andes. Analyses incorporating distances around these barriers suggest that the entire South American range of An. darlingi is at mutation–dispersal–drift equilibrium. Because the species is distributed throughout such a broad area, the limited dispersal across some landscape types promotes differentiation between otherwise proximate populations. Moreover, samples from the An. darlingi holotype location in Rio de Janeiro State are substantially derived from all other populations, implying that there may be additional genetic differences of epidemiological relevance. The results obtained contribute to our understanding of gene flow in this species and allow the formulation of human mosquito health protocols in light of the potential population differences in vector capacity or tolerance to control strategies.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 97 , 854–866.  相似文献   

16.
Examination of 248 adult specimens of whitemouth croaker Micropogonias furnieri from five localities along the Brazilian coast revealed 8735 parasites belonging to 41 metazoan species. Samples from Ceará to Bahia and Rio de Janeiro to Santa Catarina showed a high level of correct assignation (92 and 87%, respectively) and cross assignation (i.e. almost all specimens misidentified in Ceará were assigned to Bahia and almost all specimens misidentified in Bahia were classified as Ceará), so samples were pooled in the northern and south‐eastern samples, and Rio Grande do Sul was considered a southern area. Eight parasite species were characteristic of the northern localities, five species were found just in the area associated with south‐eastern localities and two species were characteristic of the southern area providing first evidence of stock discreteness. The multivariate discriminant analysis successfully discriminated three groups of localities associated with three stocks of M. furnieri in Brazil: a northern stock associated with Ceará and Bahia, a south‐eastern stock related to Rio de Janeiro and Santa Catarina and a southern stock in the area of Rio Grande do Sul, which could be considered as the northern limit of the stock associated with the Common Fishing Zone of Uruguay and Argentina.  相似文献   

17.
18.
A new species of Hybanthus (Violaceae) from north-eastern Brazil is described and illustrated. Hybanthus verrucosus Paula-Souza is endemic to 'caatingas' of Bahia and Alagoas states and is very distinct from all other Brazilian species of the genus, for its anterior petal, which is covered with small wart-like outgrowths. Other distinctive characteristics of the new species and its relationship with a closely related species ( H. atropurpureus (A.St.-Hil.) Taub.) are discussed.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 141 , 503–506.  相似文献   

19.
Procamallanus (Spirocamallanus) halitrophus Fusco and Overstreet, 1978 from the intestines of flounders (Syacium papillosum and Citharichthys macrops) from the coast of the State of Rio de Janeiro, Brazil, is redescribed. This study, which is based on results obtained by light and scanning electron microscopy, clarifies many morphological aspects of this species. Some taxonomic features, such as the cephalic structures, the topography of the cuticle, the vulva, the localization of caudal papillae on males, and the excretory pore, are observed for the first time. C. macrops represents a new host record, and Rio de Janeiro is a new geographical record for this species.  相似文献   

20.
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