scholarly journals Diversification history and hybridisation of Dacrydium (Podocarpaceae) in remote Oceania

2011 ◽  
Vol 59 (3) ◽  
pp. 262 ◽  
Author(s):  
Gunnar Keppel ◽  
Peter Prentis ◽  
Ed Biffin ◽  
Paul Hodgskiss ◽  
Susana Tuisese ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
New Caledonia ◽  
The Other ◽  
Evolutionary Relationships ◽  
Restricted Range ◽  
Long Distance Dispersal ◽  
Long Distance ◽  
Low Genetic Diversity ◽  
Cpdna Sequence ◽  
Relaxed Molecular Clock

We examined evolutionary relationships, hybridisation and genetic diversity in species of Dacrydium (Podocarpaceae) in Remote Oceania, where it is restricted to New Caledonia and Fiji. We used cpDNA sequence (trnL–trnF) data to construct a phylogeny and estimate taxon divergence by using a relaxed molecular clock approach. The phylogeny was verified using allozymes, which were also used to investigate genetic diversity of all species and the hybridisation dynamics of two endangered species, D. guillauminii and D. nidulum. Our results suggested that Dacrydium species in Remote Oceania form a monophyletic group that arose and diversified within the last 20 million years through long-distance dispersal and a range of speciation mechanisms. Whereas we detected no hybridisation between the Fijian species D. nausoriense and D. nidulum, we confirmed hybridisation between D. guillauminii and D. araucarioides in New Caledonia and determined introgression to be assymetric from the widespread D. araucarioides into the rare, restricted-range species D. guillauminii. In addition, D. guillauminii had lower genetic diversity than did the other species of Dacrydium studied, which had genetic diversity similar to that of other gymnosperms. Our results provided evidence for the recent and complex diversification of Dacrydium in Remote Oceania. In addition, low genetic diversity of and introgression from D. araucarioides, are of grave concern for the conservation of D. guillauminii.

scholarly journals Long-Distance Dispersal Shaped Patterns of Human Genetic Diversity in Eurasia

2015 ◽  
Vol 33 (4) ◽  
pp. 946-958 ◽  
Author(s):  
Isabel Alves ◽  
Miguel Arenas ◽  
Mathias Currat ◽  
Anna Sramkova Hanulova ◽  
Vitor C. Sousa ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Long Distance Dispersal ◽  
Long Distance

Austropuccinia psidii (myrtle rust).

2021 ◽  
Author(s):  
Angus J. Carnegie ◽  
Fiona R. Giblin
Keyword(s):  
Host Range ◽  
New Caledonia ◽  
Rust Fungus ◽  
Optimal Conditions ◽  
Long Distance Dispersal ◽  
Long Distance ◽  
Invasive Pathogen ◽  
Pimenta Dioica ◽  
Austropuccinia Psidii ◽  
Long Distance Movement

Abstract Austropuccinia psidii is a rust fungus with a wide and expanding host range within the Myrtaceae, with over 440 host species currently known (Carnegie and Lidbetter, 2012; Morin et al., 2012; Pegg et al., 2014). Like many rusts, urediniospores of A. psidii can be wind-dispersed over long distances. Viable spores have been detected on clothing and personal effects following visits to rust-affected plantations (Langrell et al., 2003), and this is a viable pathway for dispersal. Furthermore, there are several instances of (accidental) long-distance movement of A. psidii on diseased plants, both within and between continents (Loope et al., 2007; Kawanishi et al., 2009; Carnegie and Cooper, 2011; Zambino and Nolan, 2012). Under sub-optimal conditions, the rust can remain un-symptomatic within plants for more than a month (Carnegie and Lidbetter, 2012). This combination of wide host range and ease of long-distance dispersal make A. psidii a successful invasive pathogen. It has spread quickly once established in new countries, including Jamaica (MacLachlan, 1938), Hawaii (Uchida and Loope, 2009), Australia (Carnegie and Cooper, 2011; Pegg et al., 2014) and New Caledonia (DAVAR Nouvelle-Calédonie, 2014). Severe impact on a range of Myrtaceae has been recorded in amenity plantings, commercial plantations and the native environment. A. psidii was first identified as an invasive pathogen in the 1930s when it caused extensive damage to allspice (Pimenta dioica) plantations in Jamaica (Smith, 1935; MacLachlan, 1938). A. psidii has been identified as a quarantine risk for some time in many countries including Australia (Australian Quarantine Service, 1985; Grgurinovic et al., 2006), South Africa (Coutinho et al., 1998) and New Zealand (Kriticos and Leriche, 2008).

New species of Crotonia (Acari: Oribatida: Crotoniidae) from Lord Howe and Norfolk Islands: further evidence of long-distance dispersal events in the biogeography of a genus of Gondwanan relict oribatid mites

Zootaxa ◽  
2010 ◽  
Vol 2650 (1) ◽  
pp. 1
Author(s):  
MATTHEW J. COLLOFF
Keyword(s):  
New Species ◽  
New Zealand ◽  
New Caledonia ◽  
Oribatid Mite ◽  
Species Group ◽  
Oceanic Islands ◽  
Long Distance Dispersal ◽  
Long Distance ◽  
Lord Howe Island ◽  
Norfolk Island

Three new species of oribatid mite belonging to the genus Crotonia are described: one from Lord Howe Island (C. gorgonia sp. nov.) and two (C. norfolkensis sp. nov. and C. utricularia sp. nov.) from Norfolk Island, South-west Pacific. Crotonia gorgonia sp. nov. belongs to the Capistrata species group which reaches its highest diversity in Australia but is absent from New Zealand. Crotonia norfolkensis sp. nov. is a member of the Cophinaria group, recorded from Australia, New Zealand and New Caledonia, but with closest morphological similarity to C. brachyrostrum (Hammer, 1966) from New Zealand. Crotonia utricularia sp. nov. belongs to the Unguifera group, which reaches its highest diversity in New Zealand, is absent from Australia, and is present on Vanuatu and the Marquesas. The distribution of members of the species-groups of Crotonia in the south-western Pacific indicates that the species from Lord Howe Island has affinities with species from Australia, while the species from Norfolk Island are both most similar to species from New Zealand, and represents further evidence of the capacity of Crotonia spp. for long-distance dispersal to oceanic islands.

scholarly journals Genetic variation in the emblematic Puya raimondii (Bromeliaceae) from Huascarán National Park, Peru

2013 ◽  
Vol 13 (1) ◽  
pp. 67-74 ◽  
Author(s):  
Claudia Teresa Hornung-Leoni ◽  
Victoria Sosa ◽  
June Simpson ◽  
Katia Gil
Keyword(s):  
Genetic Diversity ◽  
Cluster Analysis ◽  
Genetic Variation ◽  
Gene Flow ◽  
Genetic Variability ◽  
National Park ◽  
Conservation Strategies ◽  
Long Distance Dispersal ◽  
Long Distance ◽  
Mountain Systems

Puya raimondii, the giant Peruvian and Bolivian terrestrial bromeliad, is an emblematic endemic Andean species well represented in Huascarán National Park in Peru. This park is the largest reserve of puna (high altitude plateau) vegetation. The objective of this study is to report on genetic variation in populations of P. raimondii from Huascarán and neighboring areas. AFLP profiles with four selective primer combinations were retrieved for 60 individuals from different zones. Genetic variability was estimated and a total of 172 bands were detected, of which 79.1% were polymorphic loci. The results showed genetic differentiation among populations, and gene flow. A cluster analysis showed that individuals of P. raimondii populations located in different mountain systems could be grouped together, suggesting long distance dispersal. Thus, conservation strategies for P. raimondii have to take into account exchange between populations located far apart in distance in order to preserve the genetic diversity of this showy species.

scholarly journals Molecular Studies of New Zealand Fucales: Phylogeography, Phylogeny and Taxonomy in Carpophyllum and Cystophora (Phaeophyceae)

2021 ◽  
Author(s):  
◽  
Joe Buchanan
Keyword(s):  
New Zealand ◽  
Genetic Distances ◽  
Internal Transcribed Spacers ◽  
Secondary Contact ◽  
Long Distance Dispersal ◽  
Long Distance ◽  
Low Genetic Diversity ◽  
Limited Dispersal ◽  
Species Descriptions ◽  
Spacer Variation

<p>Genetic variation in Carpophyllum Greville and Cystophora J. Agardh (Fucales, Phaeophyceae) was investigated at a variety of scales. An extensive survey of mitochondrial spacer variation in Carpophyllum maschalocarpum from 32 populations around New Zealand shows strong population differentiation at relatively small scales (50–100 kilometres), but also pathways of long distance dispersal that connect populations over much greater distances. In addition, historical climate change appears to have restricted C. maschalocarpum to the northern North Island during the last glacial maximum, with subsequent southward range expansion revealed by low genetic diversity in southern populations. These results are consistent with limited dispersal at the gamete and zygote stage, expected in fucalean algae, but with occasional long distance dispersal by detached floating thalli. The genetic signature suggests these two modes of dispersal are decoupled. Internal Transcribed Spacers sequences show little differentiation between C. maschalocarpum and C. angustifolium, and hybridisation was found in several populations where these species are broadly sympatric. In the Bay of Plenty the two species had different ITS ribotypes, but most C. angustifolium specimens had a mitochondrial spacer haplotype that clustered with C. maschalocarpum haplotypes. This indicates mitochondrial introgression from C. maschalocarpum into C. angustifolium. In Northland species were difficult to separate by morphology or molecular markers, and some populations appear to be comprised entirely of hybrids. Genetic distances between different species of Cystophora are very variable, and in some cases intra-species distances are similar to interspecies distances. This is problematic for DNA barcoding methods that rely on thresholds between inter-species and intra-species genetic distances. In some (but not all) cases, the absence of molecular differentiation can be attributed to oversplitting of Cystophora species by morphological methods, and I synonymise C. congesta with C. retroflexa, and C. distenta with C. scalaris. These studies exemplify the difficulties of delimiting species in brown algae: Morphology is often misleading or uninformative; genetic differentiation of species is very variable and often low; and species’ histories show complex patterns of isolation and secondary contact. I argue for an explicitly historical concept of species, with species’ history included in species descriptions.</p>

Longevity of light- and dark-colored basidiospores from saprotrophic mushroom-forming fungi

Mycologia ◽  
2018 ◽  
Vol 110 (1) ◽  
pp. 131-135 ◽  
Author(s):  
Nguyen
Keyword(s):  
Ectomycorrhizal Fungi ◽  
The Other ◽  
Optimal Conditions ◽  
Long Distance Dispersal ◽  
Ecological Strategies ◽  
Long Distance ◽  
Extended Longevity ◽  
Spore Longevity ◽  
Over Time ◽  
Basidiomycete Fungi

Fungi can produce resistant propagules that may last for decades. Basidiospores from ectomycorrhizal fungi had been experimentally shown to last for at least 6 yr, but there are few reports on the longevity of saprotrophic members of mushroom-forming fungi. Here, the author shows evidence of spore longevity of these fungi by collecting, drying, storing, and germinating these spores over time. Results showed that dark-colored spores have a much-extended longevity as compared to light-colored spores. Dark-colored spores of some species are viable to at least 2.8 yr, whereas light-colored spores are generally viable for a much shorter period of time. The author proposes that mushroom-forming basidiomycete fungi employ two different ecological strategies: one with extended longevity that allows for long-distance dispersal, and the other takes advantage of optimal conditions that support both mushroom formation, basidiospore dispersal, and germination locally.

scholarly journals Limited long-distance dispersal success in a Western European fairy shrimp evidenced by nuclear and mitochondrial lineage structuring

2019 ◽  
Vol 66 (3) ◽  
pp. 227-237
Author(s):  
Paula C Rodríguez-Flores ◽  
Ernesto Recuero ◽  
Yolanda Jiménez-Ruiz ◽  
Mario García-París
Keyword(s):  
Genetic Diversity ◽  
Gene Flow ◽  
Iberian Peninsula ◽  
Isolation By Distance ◽  
Local Scale ◽  
Long Distance Dispersal ◽  
Evolutionary Potential ◽  
Long Distance ◽  
Widespread Species ◽  
Spatio Temporal

Abstract Anostraca are known by their ability for long-distance dispersal, but the existence in several species of deep, geographically structured mtDNA lineages suggests their populations are subjected to allopatric differentiation, isolation, and prevalence of local scale dispersion. Tanymastix stagnalis is one of the most widespread species of Anostraca and previous studies revealed an unclear geographical pattern of mtDNA genetic diversity. Here, we analyze populations from the Iberian and Italian Peninsulas, Central Europe, and Scandinavia, with the aim to characterize the patterns of genetic diversity in a spatio-temporal framework using mtDNA and nuclear markers to test gene flow among close populations. For these aims we built a time-calibrated phylogeny and carried out Bayesian phylogeographic analyses using a continuous diffusion model. Our results indicated that T. stagnalis presents a deeply structured genetic diversity, including 7 ancient lineages, some of them even predating the Pleistocene. The Iberian Peninsula harbors high diversity of lineages, with strong isolation and recent absence of gene flow between populations. Dispersal at local scale seems to be the prevailing dispersal mode of T. stagnalis, which exhibits a pattern of isolation-by-distance in the Iberian Peninsula. We remark the vulnerability of most of these lineages, given the limited known geographic distribution of some of them, and the high risk of losing important evolutionary potential for the species.

scholarly journals Statistical Comparison of Trait-Dependent Biogeographical Models Indicates That Podocarpaceae Dispersal Is Influenced by Both Seed Cone Traits and Geographical Distance

2019 ◽  
Vol 69 (1) ◽  
pp. 61-75 ◽  
Author(s):  
Kristina V Klaus ◽  
Nicholas J Matzke
Keyword(s):  
Model Comparison ◽  
New Caledonia ◽  
Geographic Distance ◽  
Information Criterion ◽  
Model Parameters ◽  
Long Distance Dispersal ◽  
Long Distance ◽  
Model Weight ◽  
Dispersal Probability ◽  
Dated Phylogeny

Abstract The ability of lineages to disperse long distances over evolutionary timescales may be influenced by the gain or loss of traits adapted to enhance local, ecological dispersal. For example, some species in the southern conifer family Podocarpaceae have fleshy cones that encourage bird dispersal, but it is unknown how this trait has influenced the clade’s historical biogeography, or its importance compared with other predictors of dispersal such as the geographic distance between regions. We answer these questions quantitatively by using a dated phylogeny of 197 species of southern conifers (Podocarpaceae and their sister family Araucariaceae) to statistically compare standard, trait-independent biogeography models with new BioGeoBEARS models where an evolving trait can influence dispersal probability, and trait history, biogeographical history, and model parameters are jointly inferred. We validate the method with simulation-inference experiments. Comparing all models, those that include trait-dependent dispersal accrue 87.5% of the corrected Akaike Information Criterion (AICc) model weight. Averaged across all models, lineages with nonfleshy cones had a dispersal probability multiplier of 0.49 compared with lineages with fleshy cones. Distance is included as a predictor of dispersal in all credible models (100% model weight). However, models with changing geography earned only 22.0% of the model weight, and models submerging New Caledonia/New Zealand earned only 0.01%. The importance of traits and distance suggests that long-distance dispersal over macroevolutionary timespans should not be thought of as a highly unpredictable chance event. Instead, long-distance dispersal can be modeled, allowing statistical model comparison to quantify support for different hypotheses.

Sign in / Sign up

Export Citation Format

Share Document