DNA barcoding reveals cryptic diversity and peculiar phylogeographic patterns in mojarras (Perciformes: Gerreidae) from the Caribbean and South-western Atlantic

Author(s):  
Uedson Pereira Jacobina ◽  
Rodrigo Augusto Torres ◽  
Paulo Roberto Antunes de Mello Affonso ◽  
Ewerton Vieira dos Santos ◽  
Leonardo Luiz Calado ◽  
...  

AbstractThe mojarras (Eucinostomus) are a widespread group of coastal fishes of controversial taxonomy because of similarities in their external morphology. In the present study, we assessed the genetic diversity of species and populations of Eucinostomus using DNA barcodes using a systematic and phylogeographic context. In total, 416 COI sequences of all valid Eucinostomus representatives were analysed based on public databases and collected specimens from the north-eastern coast of Brazil (Western South Atlantic). Several cases of misidentification were detected in the barcode dataset (E. argenteus, E. harengulus, E. gula, E. dowii and E. jonesii) that could account for the taxonomic issues in this genus. In contrast, we identified four molecular operational taxonomic units (MOTUs), with divergence above 2% in the Western Atlantic, that correspond to cryptic forms within E. argenteus, E. harengulus, E. gula and E. melanopterus. These data suggest that Plio-Pleistocene events (rise of the Panama isthmus, Amazonas outflow and sea-level fluctuations) played a major role in the diversification of mojarras. While subtle morphological differences have been used as proxies to discriminate Eucinostomus species, the genetic data proved to be efficient in differentiating them and revealing potentially undescribed taxa. Therefore, we recommend that further taxonomic studies in mojarras should incorporate DNA-based evidence.

Author(s):  
Humberto F. M. Fortunato ◽  
Thierry Pérez ◽  
Gisele Lôbo-Hajdu

AbstractThe Order Suberitida is defined as a group of marine sponges without an obvious cortex, a skeleton devoid of microscleres, and with a deletion of a small loop of 15 base pairs in the secondary structure of the 28S rDNA as a molecular synapomorphy. Suberitida comprises three families and 26 genera distributed worldwide, but mostly in temperate and polar waters. Twenty species were reported along the entire Brazilian coast, and although the north-eastern coast of Brazil seems to harbour a rich sponge fauna, our current knowledge is concentrated along the south-eastern Atlantic coast. A survey was implemented along the northern coast of Brazil, and the collection allowed the identification of six species belonging to the Order Suberitida. Two of them are considered new to science: Suberites purpura sp. nov., Hymeniacidon upaonassu sp. nov., and four, Halichondria (Halichondria) marianae Santos, Nascimento & Pinheiro, 2018, Halichondria (H.) melanadocia de Laubenfels, 1936, Suberites aurantiacus (Duchassaing & Michelotti, 1864), and Terpios fugax Duchassaing & Michelotti, 1864, are re-described. Taxonomic comparisons are made for Tropical Western Atlantic species and type species of the four genera. Finally, an identification key for the Western Atlantic Suberites species is provided.


2017 ◽  
Vol 98 (7) ◽  
pp. 1619-1644 ◽  
Author(s):  
Alexandre Dias Pimenta ◽  
Bruno Garcia Andrade ◽  
Ricardo Silva Absalão

A taxonomic revision of the Nystiellidae from Brazil, including samples from the Rio Grande Rise, South Atlantic, was performed based on shell morphology. Five genera and 17 species were recognized. For the richest genus,Eccliseogyra, the three species previously recorded from Brazil were revised:E. brasiliensisandE. maracatu, previously known only from their respective type series, were re-examined. Newly available material ofE. maracatuexpanded the known geographic range of this species to off south-east Brazil.Eccliseogyra nitidais now recorded from north-eastern to south-eastern Brazil, as well as from the Rio Grande Rise. Three species ofEccliseogyraare newly recorded from the South Atlantic:E. monnioti, previously known from the north-eastern Atlantic, occurs off eastern Brazil and on the Rio Grande Rise; its protoconch is described for the first time, confirming its family allocation.Eccliseogyra pyrrhiasoccurs off eastern Brazil and on the Rio Grande Rise, andE. folinioff eastern Brazil. The genusIphitusis newly recorded from the South Atlantic.Iphitus robertsiwas found off northern Brazil, although the shells show some differences from the type material, with less-pronounced spiral keels. Additional new finds showed thatIphitus cancellatusranges from eastern Brazil to the Rio Grande Rise, and Iphitusnotiossp. nov. is restricted to the Rio Grande Rise.Narrimania, previously recorded from Brazil based on dubious records, is confirmed, including the only two living species described for the genus:N. azelotes, previously only known from the type locality in Florida, andN. concinna, previously known from the Mediterranean. A third species,Narrimania raquelaesp. nov. is described from eastern Brazil, diagnosed by its numerous and thinner cancellate sculpture. To the three species ofOpaliopsispreviously known from Brazil, a fourth species,O. arnaldoisp. nov., is added from eastern Brazil, and diagnosed by its very thin spiral sculpture, absence of a varix, and thinner microscopic parallel axial striae.Papuliscala nordestina, originally described from north-east Brazil, is recorded off eastern Brazil and synonymized withP. elongata, a species previously known only from the North Atlantic.


Author(s):  
Guidomar O. Soledade ◽  
Mariana Terossi ◽  
Justin A. Scioli ◽  
Fernando Luis Mantelatto ◽  
Alexandre O. Almeida

Alpheus macrocheles (Hailstone, 1835), a species originally described from the northeastern Atlantic, has been reported from Brazil based on material from the north and northeast coasts and Espírito Santo. However, a thorough morphological comparison between Brazilian material reported as A. macrocheles and eastern Atlantic material of A. macrocheles revealed consistent differences, suggesting that the Brazilian specimens belong to an undescribed species. Alpheus ramosportoae sp. nov. is therefore now described based on material from Amapá to Pernambuco, Brazil. Morphological differences between the new species and A. macrocheles s. str. were supported by the clear divergence of 16S rRNA gene sequences (18% of genetic distance), separating the species in two distinct clades. Differences in the color pattern also were observed and illustrated.


2018 ◽  
Vol 14 (2) ◽  
pp. 402-410 ◽  
Author(s):  
Mariacristina Prampolini ◽  
Christopher Gauci ◽  
Anton S. Micallef ◽  
Lidia Selmi ◽  
Vittoria Vandelli ◽  
...  

2021 ◽  
Vol 4 (4) ◽  
Author(s):  
SIBELLE MAKSOUD ◽  
MOUNIR MAALOUF ◽  
RAMY MAALOUF ◽  
DANY AZAR

Two new fossiliferous amber outcrops in the heights of Baskinta and Bqaatouta (El-Maten and Kesserouan districts, Central Lebanon) are described. These new discoveries constitute respectively the 27th and 28th amber outcrops with biological inclusions in Lebanon, enrich and improve our knowledge about the palaeobiodiversity and palaeoenvironment of the North-Eastern coast of Gondwana during the early Barremian.


2013 ◽  
Vol 9 (2) ◽  
pp. 969-982 ◽  
Author(s):  
M. Berger ◽  
J. Brandefelt ◽  
J. Nilsson

Abstract. In the present work the Arctic sea ice in the mid-Holocene and the pre-industrial climates are analysed and compared on the basis of climate-model results from the Paleoclimate Modelling Intercomparison Project phase 2 (PMIP2) and phase 3 (PMIP3). The PMIP3 models generally simulate smaller and thinner sea-ice extents than the PMIP2 models both for the pre-industrial and the mid-Holocene climate. Further, the PMIP2 and PMIP3 models all simulate a smaller and thinner Arctic summer sea-ice cover in the mid-Holocene than in the pre-industrial control climate. The PMIP3 models also simulate thinner winter sea ice than the PMIP2 models. The winter sea-ice extent response, i.e. the difference between the mid-Holocene and the pre-industrial climate, varies among both PMIP2 and PMIP3 models. Approximately one half of the models simulate a decrease in winter sea-ice extent and one half simulates an increase. The model-mean summer sea-ice extent is 11 % (21 %) smaller in the mid-Holocene than in the pre-industrial climate simulations in the PMIP2 (PMIP3). In accordance with the simple model of Thorndike (1992), the sea-ice thickness response to the insolation change from the pre-industrial to the mid-Holocene is stronger in models with thicker ice in the pre-industrial climate simulation. Further, the analyses show that climate models for which the Arctic sea-ice responses to increasing atmospheric CO2 concentrations are similar may simulate rather different sea-ice responses to the change in solar forcing between the mid-Holocene and the pre-industrial. For two specific models, which are analysed in detail, this difference is found to be associated with differences in the simulated cloud fractions in the summer Arctic; in the model with a larger cloud fraction the effect of insolation change is muted. A sub-set of the mid-Holocene simulations in the PMIP ensemble exhibit open water off the north-eastern coast of Greenland in summer, which can provide a fetch for surface waves. This is in broad agreement with recent analyses of sea-ice proxies, indicating that beach-ridges formed on the north-eastern coast of Greenland during the early- to mid-Holocene.


1989 ◽  
Vol 40 (5) ◽  
pp. 541 ◽  
Author(s):  
S Lavery ◽  
JB Shaklee

The genetic structure of the Australian populations of Carcharhinus tilstoni and C. sorrah was investigated by starch gel electrophoresis. Tissue samples were taken from 1580 sharks from throughout the fishery, which extends from the North-West Shelf (off Western Australia) to the north-eastern coast of Queensland. From a total of 47 enzyme loci screened in each species, 13 proved to be polymorphic (P0.99) for at least one species, with only 5 loci for each species showing sufficient variation (P0.95) to be of use in the analysis of population structure. Mean heterozygosity values were relatively low: 0.037 for C. tilstoni and 0.035 for C. sorrah. A low level of population subdivision was found within each species, with FST values of 0.0094 for C. tilstoni and 0.0076 for C. sorrah. There was insufficient evidence to suggest that there is more than one population of either species of shark in Australian waters.


2015 ◽  
Vol 23 (2) ◽  
pp. 20-30 ◽  
Author(s):  
Dávid Kováts ◽  
Andrea Harnos

Abstract In this paper, a complex morphological comparison of four Common Nightingale groups (Luscinia megarhynchos) is demonstrated. In total, 121 territorial nightingales were mist-netted and measured individually on four study areas called ‘Bódva’, ‘Felső-Tisza’, ‘Szatmár-Bereg’ and ‘Bátorliget’ in the North-Eastern part of Hungary in 2006–2013. To distinguish groups by morphology, Classification and Regression Trees (CART), Random Forest (RF) and Linear Discriminant Analysis (LDA) methods were used. Comparison of the four studied Common Nightingale groups shows substantial morphological differences in the length of the second, the third and the fourth primaries (P2, P3, P4), in bill length (BL) and bill width (BW), while other characteristics showed greater similarities. Based on the results of all the applied classification methods, birds originated from Szatmár-Bereg were clearly distinguishable from the others. The differences in morphology can be explained by interspecific competition or phenotypic plasticity resulting from the change of ecological, environmental parameters. Our case study highlights the advantageous differences of the classification methods to distinguish groups with similar morphology and to choose important variables for classification. In conclusion, broad application of the classification methods RF and CART is highly recommended in comparative ecological studies.


2019 ◽  
Vol 49 (3) ◽  
pp. 213-219
Author(s):  
Marina Figueiredo ◽  
Jorge Nunes ◽  
Zafira Almeida ◽  
Alexsandra Paz ◽  
Nivaldo Piorski ◽  
...  

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