Genetic diversity assessment for the vulnerable migratory cownose ray Rhinoptera bonasus (Myliobatiformes: Rhinopteridae) from the southwestern Atlantic Ocean

ABSTRACT Rhinoptera bonasus is a bento-pelagic and highly migratory species occurring from southern United States to northern Argentina. Due to overfishing effects, R. bonasus is currently at risk, classified by the IUCN Red List as vulnerable. Considering the lack of molecular data available for R. bonasus, this study aimed to describe the genetic variability and population structure of specimens sampled from three Brazilian coast ecoregions (Amazon ecoregion, Pará; Northeastern ecoregion, Pernambuco and Southeastern ecoregion, Rio de Janeiro, São Paulo and Santa Catarina), through five polymorphic microsatellite markers. Here testing the panmixia hypothesis for Brazilian ecoregions and test natal philopathy. A total of 69 analyzed specimens revealed individual and significant genetic differentiation between the sampled locations. Φ ST (0.12), PCA, DAPC and Bayesian analyses of the genetic population structure revealed at least two distinct genetic R. bonasus groupings. IBD tests were significant, indicating a correlation between genetic and geographical distance among populations, which can be explained by reproductive philopatric behavior. Philopatric behavior associated with R. bonasus mobility may influence the differentiation values observed for all loci in the investigated samples.

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Genetic monitoring reveals significant population structure in eastern quolls: implications for the conservation of a threatened carnivorous marsupial

Australian Mammalogy ◽

10.1071/am13035 ◽

2014 ◽

Vol 36 (2) ◽

pp. 169 ◽

Cited By ~ 7

Author(s):

Maria J. Cardoso ◽

Nick Mooney ◽

Mark D. B. Eldridge ◽

Karen B. Firestone ◽

William B. Sherwin

Keyword(s):

Population Structure ◽

Genetic Variation ◽

Geographic Distance ◽

Molecular Data ◽

Genetic Monitoring ◽

Genetic Admixture ◽

Conservation Strategies ◽

Regional Differentiation ◽

Peripheral Populations ◽

Genetic Population

The eastern quoll (Dasyurus viverrinus), while still relatively abundant in Tasmania, is now threatened by the recently introduced European red fox (Vulpes vulpes). Due to a lack of demographic information on eastern quolls, molecular data become a crucial surrogate to inform the management of the species. The aim of this study was to acquire baseline genetic data for use in current and future conservation strategies. Genetic variation, at seven microsatellite loci, was lower in Tasmanian eastern quolls than in quoll species from the Australian mainland. Within Tasmania, genetic variation was greater in central than peripheral populations, with the lowest levels detected on Bruny Island. Significant genetic population structure, consistent with regional differentiation, appears related to geographic distance among populations. Levels of gene flow appeared moderate, with genetic admixture greatest among central populations. Therefore, eastern quolls from genetically diverse central Tasmanian populations will become an important source for conservation initiatives if widespread declines begin to occur. Ongoing genetic monitoring of existing populations will allow conservation strategies to be adaptive. However, in order for translocations to be successful, managers must not only consider the genetic composition of founding individuals, but also habitat-specific adaptations, disease and threatening processes at translocation sites.

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Population Structure of Lutjanus purpureus (Lutjanidae - Perciformes) on the Brazilian coast: further existence evidence of a single species of red snapper in the western Atlantic

Anais da Academia Brasileira de Ciências ◽

10.1590/s0001-37652012000400013 ◽

2012 ◽

Vol 84 (4) ◽

pp. 979-999 ◽

Cited By ~ 18

Author(s):

Grazielle Gomes ◽

Iracilda Sampaio ◽

Horacio Schneider

Keyword(s):

Population Structure ◽

Control Region ◽

Single Species ◽

Mitochondrial Control Region ◽

Haplotype Network ◽

Molecular Data ◽

Red Snapper ◽

Brazilian Coast ◽

Base Pairs ◽

Western Atlantic

The present study focus on the mitochondrial control region to investigate phylogeographic patterns and population structure in Lutjanus purpureus, and to evaluate the genetic similarity between L. purpureus and L. campechanus. For the initial analysis, 810 base pairs sequence from control region were obtained from 239 specimens of L. purpureus collected from four localities off the Brazilian coast. The results revealed the presence of a single panmictic population characterized by high values of genetic diversity. The 299 base pairs hypervariable portion were used for the combined analysis of L. purpureus and L. campechanus, being 275 haplotypes identified in the 414 specimens. Phylogenetic tree and haplotype network did not indicate phylogeographic substructuring between the two species, but rather an intense intermingling of individuals. Considering their marked morphological similarity, the molecular data presented here indicate that only one species of red snapper exists in the western Atlantic.

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