Molecular systematics reveals multiple lineages and cryptic speciation in the freshwater crayfish Parastacus brasiliensis (von Martens, 1869) (Crustacea : Decapoda : Parastacidae)

2018 ◽  
Vol 32 (6) ◽  
pp. 1265 ◽  
Author(s):  
Ivana Miranda ◽  
Kelly M. Gomes ◽  
Felipe B. Ribeiro ◽  
Paula B. Araujo ◽  
Catherine Souty-Grosset ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Isolation By Distance ◽  
Conservation Status ◽  
Sensu Stricto ◽  
Genetic Distances ◽  
Distribution Data ◽  
Lake Basin ◽  
Gene Pools ◽  
Freshwater Crayfish ◽  
Isolated Populations

The characterisation of intraspecific genetic diversity in representatives of the South American crayfish genus Parastacus Huxley, 1879 is here carried out for the first time by comparing populations of Parastacus brasiliensis (von Martens, 1869) as currently defined. Phylogenetic reconstructions based on mitochondrial and nuclear markers indicate the existence of multiple lineages, of which only one can be considered as P. brasiliensis sensu stricto. In addition, there are seven other lineages, one of which is the subspecies Parastacus brasiliensis promatensis Fontoura & Conter, 2008, which is here elevated to species level. We thereby increase to 14 the number of recognised species within Parastacus in South America. Genetic distances among P. brasiliensis sensu stricto and the lineages ‘A’, ‘B’ and ‘C’ increase with geographical distances, suggesting isolation by distance as an important driver of diversification, and eventually speciation, in these burrowing crayfishes. Parastacus brasiliensis occurs mainly in the Guaíba Lake basin and studied populations show limited connectivity and gene flow, probably due to habitat fragmentation. On the basis of genetic and distribution data, the conservation status of P. brasiliensis sensu stricto is confirmed as Near Threatened (NT). These findings lead us to encourage the establishment of preservation areas for isolated populations. The importance of preserving the newly recognised distinct gene pools in order to maintain overall genetic diversity is emphasised.

scholarly journals Genetic Diversity and Population Divergence of a Rare, Endemic Grass (Elymus breviaristatus) in the Southeastern Qinghai-Tibetan Plateau

2019 ◽  
Vol 11 (20) ◽  
pp. 5863 ◽  
Author(s):  
Qingqing Yu ◽  
Qian Liu ◽  
Yi Xiong ◽  
Yanli Xiong ◽  
Zhixiao Dong ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Tibetan Plateau ◽  
Isolation By Distance ◽  
Genetic Distances ◽  
Conservation Strategy ◽  
Conservation Strategies ◽  
Grass Species ◽  
Population Divergence ◽  
High Genetic Diversity ◽  
Widespread Species

Elymus breviaristatus is a grass species only distributed in the southeast of Qinghai-Tibetan Plateau (QTP), which has suffered from serious habitat fragmentation. Therefore, understanding patterns of genetic diversity within and among natural E. breviaristatus populations could provide insight for future conservation strategies. In this study, sequence-related amplified polymorphism markers were employed to investigate the genetic diversity and hierarchical structure of seven E. breviaristatus populations from QTP, China. Multiple measures of genetic diversity indicated that there is low to moderate genetic variation within E. breviaristatus populations, consistent with its presumed mating system. In spite of its rarity, E. breviaristatus presented high genetic diversity that was equivalent to or even higher than that of widespread species. Bayesian clustering approaches, along with clustering analysis and principal coordinate analysis partitioned the studied populations of E. breviaristatus into five genetic clusters. Differentiation coefficients (Fst, GST, etc.) and AMOVA analysis revealed considerable genetic divergence among different populations. BARRIER analyses indicated that there were two potential barriers to gene flow among the E. breviaristatus populations. Despite these patterns of differentiation, genetic distances between populations were independent of geographic distances (r = 0.2197, p = 0.2534), indicating little isolation by distance. Moreover, despite detecting a common outlier by two methods, bioclimatic factors (altitude, annual mean temperature, and annual mean precipitation) were not related to diversity parameters, indicating little evidence for isolation caused by the environment. These patterns of diversity within and between populations are used to propose a conservation strategy for E. breviaristatus.

Genetic diversity and conservation of the endemic tuco-tuco Ctenomys ibicuiensis (Rodentia: Ctenomyidae)

2020 ◽  
Author(s):  
Mayara Delagnelo Medeiros ◽  
Daniel Galiano ◽  
Bruno Busnello Kubiak ◽  
Paula Angélica Roratto ◽  
Thales Renato Ochotorena de Freitas
Keyword(s):  
Genetic Diversity ◽  
Gene Flow ◽  
Environmental Changes ◽  
Isolation By Distance ◽  
Conservation Status ◽  
Significant Risk ◽  
Structured Populations ◽  
Small Range ◽  
High Genetic Diversity ◽  
Landscape Modification

Abstract Endemic, small range species are susceptible to environmental changes and landscape modification. Understanding genetic diversity and distributional patterns is important for implementation of effective conservation measures. In this context, genetic diversity was evaluated to update the conservation status of an endemic tuco-tuco, Ctenomys ibicuiensis. Phylogeographic and population genetic analyses of mitochondrial DNA and microsatellite loci were carried out using 46 individuals sampled across the species’ distribution. Ctenomys ibicuiensis presented moderate to high genetic diversity and highly structured populations with low levels of gene flow and isolation by distance. Anthropogenic landscape changes threaten this restricted-range tuco-tuco. Considering its limited geographic distribution and highly structured populations with low gene flow, we consider C. ibicuiensis to be at significant risk of extinction.

Status Update for Six Rare Crayfishes (Decapoda: Cambaridae) in Western North Carolina

2014 ◽  
Vol 130 (2) ◽  
pp. 25-39
Author(s):  
William T. Russ ◽  
Stephen J. Fraley
Keyword(s):  
North Carolina ◽  
Conservation Status ◽  
Limited Range ◽  
Distribution Data ◽  
Savannah River ◽  
Isolated Populations ◽  
River Drainage ◽  
Tennessee River ◽  
Western North Carolina ◽  
Little Tennessee River

Abstract From 2009–2012 detailed distribution data, information to update conservation status, and additional life history and habitat observations were obtained for six rare crayfishes in Western North Carolina. The Hiwassee Headwaters Crayfish, Cambarus (Puncticambarus) parrishi, continues to occupy a very limited range in Clay County, with most known occurrences from the Tusquitee Creek system. The Chauga Crayfish, C. (P.) chaugaensis, appears to be abundant throughout much of its range in the upper Savannah River Drainage, in Transylvania, Jackson, and Macon counties. The French Broad River Crayfish, C. (P.) reburrus, has declined in Madison and Buncombe counties, while populations in Transylvania County appear to have remained relatively stable. The Broad River Stream Crayfish, C. (Cambarus) lenati continues to occur primarily in the upper First Broad River drainage where it is common in some streams in Rutherford County. The Broad River Spiny Crayfish, C. (P.) spicatus is rare but continues to exist in two isolated populations: upper First Broad and North Pacolet river drainages. The Little Tennessee River Crayfish, C. (P.) georgiae continues to occupy Jackson and Macon counties where it is most abundant in the upper Little Tennessee River Drainage. No range expansions were observed for any of these crayfish species.

Genetic and Ecological Variation in Atherosperma moschatum and the Implications for Conservation of Its Biodiversity

1994 ◽  
Vol 42 (6) ◽  
pp. 663 ◽  
Author(s):  
A Shapcott
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
New South ◽  
Genetic Distances ◽  
Isolated Populations ◽  
Canopy Tree ◽  
South Wales ◽  
Genetic Substructure ◽  
Temperate Rainforests ◽  
Vegetative Spread

Population genetics and ecology of Atherosperma moschatum Labill. (sassafras), a major canopy tree of Australian temperate rainforests, were examined and used to identify priorities and strategies for conservation of its genetic diversity. The genetic diversity among populations was fairly low, but higher than average for long-lived late successional or wind dispersed species (Hamrick and Godt 1989). Genetic distances between populations were correlated with geographic distances and climatic differences. The major genetic differentiation was between the mainland populations and those in Tasmania, with the New South Wales populations being quite genetically distinct. Most genetic variation was found within populations, however, most populations were inbred. This is likely to be due to selfing and spatial genetic substructure resulting from vegetative spread and local dispersal. There was evidence of regeneration in all populations, however no consistent regeneration patterns emerged. Population density was inexplicably correlated with genetic distance. There was as much diversity in all variables (ecological and genetic) measured in small isolated populations as there was in stands within larger assemblages; therefore, population size does not appear to be a major factor affecting viability. Genetic variation was spread throughout the distribution of A. moschatum. Therefore, populations from throughout its range would need to be conserved to retain the genetic diversity within this species.

Assessing Genetic Diversity of Canada Thistle (Cirsium arvense) in North America with Microsatellites

Weed Science ◽  
2010 ◽  
Vol 58 (4) ◽  
pp. 387-394 ◽  
Author(s):  
Tracey A. Bodo Slotta ◽  
Michael E. Foley ◽  
Shaioman Chao ◽  
Ruth A. Hufbauer ◽  
David P. Horvath
Keyword(s):  
Genetic Diversity ◽  
Invasive Species ◽  
North America ◽  
North American ◽  
Isolation By Distance ◽  
Genetic Distances ◽  
Population Diversity ◽  
Canada Thistle ◽  
Long Distance ◽  
Distance Analysis

Invasive species such as Canada thistle pose a significant threat to ecosystems. The risk of introducing invasive species has increased with human activities, and the effects of such events have economic and aesthetic impacts. Native to Europe, Canada thistle is now established throughout temperate North America. Although there is documentation of early occurrences to North America, little is known on how it has become established in diverse habitats or how it continues to spread. We examined genetic diversity within and among nearly 1,700 Canada thistle individuals from 85 North American locations with the use of seven microsatellite markers in order to address these questions. PAUP and STRUCTURE programs were used to assess genetic diversity and relationships within and between populations. Populations exhibited greater within-population diversity (> 60%) than expected for a reported clonally reproducing species. Total diversity of sampled locations in North America (0.183) was less than previously reported for European locations (0.715), but the greater mean difference between North American populations (0.264 relative to 0.246 from England) suggests strong founder effects or restriction of gene flow influencing individual populations. Furthermore, analyses identified numerous instances where individuals from geographically distant regions clustered together, indicating long-distance translocation of propogules. However, isolation by distance analysis showed significant correlation between location and population genetic distances (r = 0.1917, P = 0.006). Within populations, nearly 92% of individuals sampled harbored unique multilocus genotypes, strongly suggesting that sexual reproduction is common. Within populations, analysis of genetic structure indicated significant admixture of genotypes throughout the invasive range in North America. The recurrent distribution of seed throughout North America has led to a highly diverse gene pool and increased the adaptive success Canada thistle to a wide variety of habitats. Future technologies developed for control of Canada thistle should consider this diversity.

scholarly journals Characterizing the genetic diversity of the Andean blueberry (Vaccinium floribundum Kunth.) across the Ecuadorian Highlands

2020 ◽  
Author(s):  
Pamela Vega-Polo ◽  
Maria M. Cobo ◽  
Andrea Argudo ◽  
Bernardo Gutierrez ◽  
Jennifer Rowntree ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Population Structure ◽  
Environmental Changes ◽  
Isolation By Distance ◽  
Anthropogenic Activities ◽  
Conservation Status ◽  
Ecological Factors ◽  
Andean Region ◽  
Key Factor ◽  
Distance Model

AbstractThe Ecuadorian páramo, a high altitude tundra-like ecosystem, is a unique source of various ecosystem services and distinct biodiversity. Anthropogenic activities are associated with its fragmentation, which alters ecological factors and directly threatens resident species. Vaccinium floribundum Kunth., commonly known as Andean blueberry or mortiño, is a wild shrub endemic to the Andean region and highly valued in Ecuador for its berries, which are widely used in food preparations and hold an important cultural value. Since it is a wild species, mortiño could be vulnerable to environmental changes, resulting in a reduction of the size and distribution of its populations. To evaluate the extent of these effects on the mortiño populations, we assessed the genetic diversity and population structure of the species along the Ecuadorian highlands. We designed and developed a set of 30 homologous SSR markers and used 16 of these to characterize 100 mortiño individuals from 27 collection sites. Our results revealed a high degree of genetic diversity (HE=0.73) for the Ecuadorian mortiño, and a population structure analyses suggested the existence of distinct genetic clusters present in the northern, central and southern highlands. A fourth, clearly differentiated cluster was also found and included individuals from locations at higher elevations. We suggest that the population structure of the species could be explained by an isolation-by-distance model and can be associated to the geological history of the Andean region. Our results suggest that elevation could also be a key factor in the differentiation of mortiño populations. This study provides an extensive overview of the species across its distribution range in Ecuador, contributing to a better understanding of its conservation status. These results can assist the development of conservation programs for this valuable biological and cultural resource and for the páramo ecosystems as a whole.

scholarly journals Genetic diversity in westernmost European populations of Halimione verrucifera (M. Bieb.) Aellen

2021 ◽  
Vol 26 (2) ◽  
pp. 2541-2547
Author(s):  
MIHNEA VLADIMIRESCU ◽  
◽  
IOANA CĂTĂLINA PAICA ◽  
CRISTIAN BANCIU ◽  
GABRIEL MIHAI MARIA ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Conservation Status ◽  
Diversity Indices ◽  
Genetic Distances ◽  
Marginal Populations ◽  
Banding Patterns ◽  
Pcr Products ◽  
South Eastern Europe ◽  
Hardy Weinberg Equilibrium ◽  
Population Survival

Halimione verrucifera – an extreme halophyte plant species spread mainly in Asia with a few locations in South Eastern Europe – have the westernmost marginal populations in Romania. In order to asses population fitness and conservation status, genetic diversity among and within population was estimated using ISSR markers.A set of 6 primers were utilized after selection from a primer set which showed clear and reproducible banding patterns, generating a total number of 86 loci. A presence/absence matrix was generated by evaluating the gel electrophoresis banding patterns of PCR products. From this, genetic distances between individuals and populations were calculated, which were used in all subsequent generation of genetic diversity indices, assuming the Hardy-Weinberg equilibrium. Result revealed a low expected heterozygosity for both populations. Further testing by constructing an UPGMA dendrogram and a PCoA analysis confirmed that populations are clearly separated and with levels of genetic diversity that could ensure population survival in time and space.

scholarly journals New records and conservation of Passiflora L. (Passifloraceae s.s.) in Rio de Janeiro, Brazil

2021 ◽  
Vol 16 (1) ◽  
pp. 115-128
Author(s):  
Michaele Alvim Milward-de-Azevedo ◽  
Natália Brandão Gonçalves Fernandes
Keyword(s):  
Rio De Janeiro ◽  
New Records ◽  
Conservation Status ◽  
Sensu Stricto ◽  
Distribution Data ◽  
Distribution Maps ◽  
Area Of Occupancy ◽  
The Family ◽  
First Time ◽  
Janeiro State

Passiflora L. belongs to the family Passifloraceaesensu stricto, and comprises 700–750 species. There are approximately 161 known species of the family in Brazil, of which 153 belong to Passiflora, 89 are endemic, 83 occur in the region of the Atlantic Domain; 40 occur in Rio de Janeiro State (RJ). Using field samplings techniques and scientific collection analyses, we present here new geographic records for Passiflora deidamioides Harms, P. imbeana Sacco, P. junqueirae Imig & Cervi, and P. truncata Regel for RJ, principally in the Serra dos Órgãos National Park (PARNASO). Geographic distribution data was used to calculate the Extension of Occurrence (EOO) and Area of Occupancy (AOO) of the species. Passiflora junqueirae, previously considered endemic to Espírito Santo State, now has new records for RJ. Passiflora imbeana and P. truncata are extended into RJ, being recorded there for the first time in the municipality of Teresópolis. The four species are cited for the first time in PARNASO, occurring between 1,000 and 1,700 m.a.s.l. in Montane and Upper Montane Atlantic Rainforest. We provide taxonomic information, distribution maps, and the conservation status of the species.

scholarly journals Characterizing the genetic diversity of the Andean blueberry (Vaccinium floribundum Kunth.) across the Ecuadorian Highlands

PLoS ONE ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. e0243420
Author(s):  
Pamela Vega-Polo ◽  
Maria Mercedes Cobo ◽  
Andrea Argudo ◽  
Bernardo Gutierrez ◽  
Jennifer Rowntree ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Population Structure ◽  
Environmental Changes ◽  
Isolation By Distance ◽  
Anthropogenic Activities ◽  
Conservation Status ◽  
Ecological Factors ◽  
Andean Region ◽  
Key Factor ◽  
Species Specific

The Ecuadorian páramo, a high altitude tundra-like ecosystem, is a unique source of various ecosystem services and distinct biodiversity. Anthropogenic activities are associated with its fragmentation, which alters ecological factors and directly threatens resident species. Vaccinium floribundum Kunth., commonly known as Andean blueberry or mortiño, is a wild shrub endemic to the Andean region and highly valued in Ecuador for its berries, which are widely used in food preparations and hold an important cultural value. Since it is a wild species, mortiño could be vulnerable to environmental changes, resulting in a reduction of the size and distribution of its populations. To evaluate the extent of these effects on the mortiño populations, we assessed the genetic diversity and population structure of the species along the Ecuadorian highlands. We designed and developed a set of 30 species-specific SSR (simple sequence repeats) markers and used 16 of these to characterize 100 mortiño individuals from 27 collection sites. Our results revealed a high degree of genetic diversity (HE = 0.73) for the Ecuadorian mortiño, and a population structure analyses suggested the existence of distinct genetic clusters present in the northern, central and southern highlands. A fourth, clearly differentiated cluster was also found and included individuals from locations at higher elevations. We suggest that the population structure of the species could be explained by an isolation-by-distance model and can be associated with the geological history of the Andean region. Our results suggest that elevation could also be a key factor in the differentiation of mortiño populations. This study provides an extensive overview of the species across its distribution range in Ecuador, contributing to a better understanding of its conservation status. These results can assist in the development of conservation programs for this valuable biological and cultural resource and for the páramo ecosystem as a whole.

scholarly journals GENETIC DIVERSITY STUDIES OF LATVIAN VACCINIUM MYRTILLUS L. POPULATIONS FOR IN SITU CONSERVATION

AGROFOR ◽  
2019 ◽  
Vol 4 (3) ◽  
Author(s):  
Agnese GAILĪTE ◽  
Anita GAILE ◽  
Dainis RUŅĢIS
Keyword(s):  
Genetic Diversity ◽  
Isolation By Distance ◽  
In Situ Conservation ◽  
Crop Wild Relatives ◽  
Vaccinium Myrtillus ◽  
Conservation Strategies ◽  
Forest Types ◽  
Isolated Populations ◽  
Vaccinium Myrtillus L

Plants and berries of bilberries (Vaccinium myrtillus L.) are traditionally used in many nations as a local medicine as well as edible plants. They are an important feed source for wild animals and birds. In situ conservation is an important component for the conservation of crop wild relatives (CWR) and wild harvested plants (WHP). Research on population structure and genetic diversity is important and is required for the development and implementation of in situ conservation strategies as well as being useful for ecosystem services management. The aim of this study was to test EST-SSR markers for bilberry genotyping and determine genetic diversity in different forest types – Vacciniosa, Myrtillosa, Hylocomiosa as well as compare populations from various regions of Latvia. Our results indicated that there was a small genetic differentiation between bilberries grown in different forest types (0-2%); most of the variation was found within individuals. Analysing populations in different regions of Latvia, 5% of the genetic variation was found among populations. Analysis using the STRUCTURE software package showed that there were no isolated populations or distinct groups. There was a positive correlation between geographic and genetic distances, indicating that the analysed populations differentiation can be explained by isolation-by-distance, without additional dispersal barriers.

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