scholarly journals Pronounced Genetic Separation Among Varieties of thePrimula cusickianaSpecies Complex, a Great Basin Endemic

2021 ◽  
Author(s):  
Austin Koontz ◽  
William D. Pearse ◽  
Paul Wolf
Keyword(s):  
Genetic Structure ◽  
Great Basin ◽  
Species Complex ◽  
Breeding Systems ◽  
Allopatric Speciation ◽  
Isolated Populations ◽  
Fragmented Habitats ◽  
Species Complexes ◽  
Varietal Classification ◽  
Sky Island

AbstractDistinguishing between unique species and populations with strong genetic structure is a common challenge in population genetics, especially in fragmented habitats where allopatric speciation may be widespread and distinct groups may be morphologically similar. Such is often the case with species complexes across sky island environments. In these scenarios, biogeography may help to explain the relations between species complex members, and RADseq methods are commonly used to compare closely related species across thousands of genetic loci. Here we use RADseq to clarify the relations between geographically distinct but morphologically similar varieties of thePrimula cusickianaspecies complex, and to contextualize past findings of strong genetic structure among populations within varieties. Our genomic analyses demonstrate pronounced separation between isolated populations of this Great Basin endemic, indicating that the current varietal classification of complex members is inaccurate and emphasizing their conservation importance. We discuss how these results correspond to recent biogeographical models used to describe the distribution of other sky island taxa in western North America. Our findings also fit into a wider trend observed for alpinePrimulaspecies complexes, and we consider how heterostylous breeding systems may be contributing to frequent diversification via allopatric speciation in this genus.

Strict allopatric speciation of sky island Pyrrhula erythaca species complex

2020 ◽  
Vol 153 ◽  
pp. 106941
Author(s):  
Feng Dong ◽  
Shou-Hsien Li ◽  
Chi-Cheng Chiu ◽  
Lu Dong ◽  
Cheng-Te Yao ◽  
...  
Keyword(s):  
Species Complex ◽  
Allopatric Speciation ◽  
Sky Island

scholarly journals Highly restricted dispersal in habitat-forming seaweed may impede natural recovery of disturbed populations

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Florentine Riquet ◽  
Christiane-Arnilda De Kuyper ◽  
Cécile Fauvelot ◽  
Laura Airoldi ◽  
Serge Planes ◽  
...  
Keyword(s):  
Genetic Structure ◽  
Spatial Scales ◽  
Mediterranean Ecosystems ◽  
Dispersal Distance ◽  
Genetic Connectivity ◽  
Restricted Gene Flow ◽  
Isolated Populations ◽  
Natural Recovery ◽  
Limited Dispersal ◽  
Ecological Importance

AbstractCystoseira sensu lato (Class Phaeophyceae, Order Fucales, Family Sargassaceae) forests play a central role in marine Mediterranean ecosystems. Over the last decades, Cystoseira s.l. suffered from a severe loss as a result of multiple anthropogenic stressors. In particular, Gongolaria barbata has faced multiple human-induced threats, and, despite its ecological importance in structuring rocky communities and hosting a large number of species, the natural recovery of G. barbata depleted populations is uncertain. Here, we used nine microsatellite loci specifically developed for G. barbata to assess the genetic diversity of this species and its genetic connectivity among fifteen sites located in the Ionian, the Adriatic and the Black Seas. In line with strong and significant heterozygosity deficiencies across loci, likely explained by Wahlund effect, high genetic structure was observed among the three seas (ENA corrected FST = 0.355, IC = [0.283, 0.440]), with an estimated dispersal distance per generation smaller than 600 m, both in the Adriatic and Black Sea. This strong genetic structure likely results from restricted gene flow driven by geographic distances and limited dispersal abilities, along with genetic drift within isolated populations. The presence of genetically disconnected populations at small spatial scales (< 10 km) has important implications for the identification of relevant conservation and management measures for G. barbata: each population should be considered as separated evolutionary units with dedicated conservation efforts.

scholarly journals Optimal markers for the identification ofColletotrichumspecies

2019 ◽  
Author(s):  
Willie Anderson dos Santos Vieira ◽  
Priscila Alves Bezerra ◽  
Anthony Carlos da Silva ◽  
Josiene Silva Veloso ◽  
Marcos Paz Saraiva Câmara ◽  
...  
Keyword(s):  
Molecular Markers ◽  
Species Complex ◽  
Plant Pathogens ◽  
Phylogenetic Signal ◽  
Intergenic Spacer ◽  
Internal Transcribed Spacers ◽  
Type Locus ◽  
Phylogenetic Studies ◽  
Fungal Plant Pathogens ◽  
Species Complexes

ABSTRACTColletotrichumis among the most important genera of fungal plant pathogens. Molecular phylogenetic studies over the last decade have resulted in a much better understanding of the evolutionary relationships and species boundaries within the genus. There are now approximately 200 species accepted, most of which are distributed among 13 species complexes. Given their prominence on agricultural crops around the world, rapid identification of a large collection ofColletotrichumisolates is routinely needed by plant pathologists, regulatory officials, and fungal biologists. However, there is no agreement on the best molecular markers to discriminate species in each species complex. Here we calculate the barcode gap distance and intra/inter-specific distance overlap to evaluate each of the most commonly applied molecular markers for their utility as a barcode for species identification. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), histone-3 (HIS3), DNA lyase (APN2), intergenic spacer between DNA lyase and the mating-type locusMAT1-2-1 (APN2/MAT-IGS), and intergenic spacer between GAPDH and a hypothetical protein (GAP2-IGS) have the properties of good barcodes, whereas sequences of actin (ACT), chitin synthase (CHS-1) and nuclear rDNA internal transcribed spacers (nrITS) are not able to distinguish most species. Finally, we assessed the utility of these markers for phylogenetic studies using phylogenetic informativeness profiling, the genealogical sorting index (GSI), and Bayesian concordance analyses (BCA). Although GAPDH, HIS3 and β-tubulin (TUB2) were frequently among the best markers, there was not a single set of markers that were best for all species complexes. Eliminating markers with low phylogenetic signal tends to decrease uncertainty in the topology, regardless of species complex, and leads to a larger proportion of markers that support each lineage in the Bayesian concordance analyses. Finally, we reconstruct the phylogeny of each species complex using a minimal set of phylogenetic markers with the strongest phylogenetic signal and find the majority of species are strongly supported as monophyletic.

scholarly journals Distribution of naked amoebae in the soils of the steppe zone of Ukraine

2020 ◽  
pp. 159-166
Author(s):  
M. Patsyuk ◽  
Keyword(s):  
Cluster Analysis ◽  
Multidimensional Scaling ◽  
Species Complex ◽  
Steppe Zone ◽  
Common Species ◽  
Molecular Clusters ◽  
The Other ◽  
Steppe Region ◽  
Species Complexes ◽  
Naked Amoebae

As a result of the study, in the steppe zone of Ukraine (Odessa, Mykolaiv, Kirovohrad region), 12 species of naked amoebas were identified, which according to the modern Eukaryot system belong to three molecular clusters Tubulinea Smirnov et al., 2005, Discosea Cavalier-Smith, 2004., Discoba Simpson and Hampl et al., 2009. This species Vahlkampfia sp. (1), Vahlkampfia sp. (2), Deuteramoeba mycophaga Page, 1988, Saccamoeba stagnicola Page, 1974, Vexillifera sp., Vannella sp. Ripellaplatypodia Smirnov, Nassonova, Chao et Cavalier-Smith, 2007, Cochliopodium sp. (1), Mayorella sp., Thecamoeba striata Penard, 1890, Stenamoeba stenopodia (Page, 1969) Smirnov et al., 2007, Acanthamoeba sp. (1). In the studied steppe soils, the most common were Vahlkampfia sp. (2), S. stenopodia, Vahlkampfia sp. (1), Vexillifera sp., Cochliopodium sp. (1); the least common – R. platypodia, D. mycophaga, T. striata, Mayorella sp. As a result of the cluster analysis, it was found that the largest share of common species is observed between Mykolaiv and Kirovograd regions (0.71) and Odessa and Kirovograd regions (0.53); the smallest is between the Odessa and Mykolaiv regions (0.43). According to the results of cluster analysis, the faunistic complexes of soil species of amoebae of the steppe region of Ukraine are united into two clusters: one of them being complexes characteristic of the Odessa region, and the other complexes of the Mykolaiv and Kirovograd regions. According to the results of nonparametric multidimensional scaling, it is established that the species complex of soil amoebae in the Kirovograd and Mykolaiv regions is determined by the increased soil temperature and acidity, compared to the Odessa region. As for moisture, this factor has little effect on the species complexes amoebae steppe region of Ukraine.

scholarly journals Influences of oceanic islands and the Pleistocene on the biogeography and evolution of two groups of Australasian parrots (Aves: Psittaciformes: Eclectus roratus, Trichoglossus haematodus complex). Rapid evolution and implications for taxonomy and conservation

2016 ◽  
Vol 3 (2) ◽  
pp. 47-66
Author(s):  
Michael P. Braun ◽  
Matthias Reinschmidt ◽  
Thomas Datzmann ◽  
David Waugh ◽  
Rafael Zamora ◽  
...  
Keyword(s):  
Species Complex ◽  
Rapid Evolution ◽  
New Guinea ◽  
Distinct Species ◽  
Genetic Evidence ◽  
Valid Species ◽  
Separate Species ◽  
Species Complexes ◽  
Mitochondrial Cytochrome B ◽  
Avian Diversification

AbstractThe Australasian region is a centre of biodiversity and endemism, mainly based on the tropical climate in combination with the large amount of islands. During the Pleistocene, islands of the Sahul Shelf (Australia, New Guinea, Aru Islands) had been part of the same land mass, while islands within the Wallacea (Lesser Sunda Islands, Moluccas, Sulawesi etc.) remained isolated. We investigated biogeographical avian diversification patterns of two species complexes across the Wallacea and the Sahul Shelf: the Eclectus Parrot Eclectus roratus Wagler, 1832, and the Rainbow Lorikeet Trichoglossus haematodus Linnaeus, 1771. Both species are represented by a large number of described geographical subspecies. We used mitochondrial cytochrome b (cyt b) sequences for phylogenetic and network analysis to detect biogeographic roles of islands and avian diversification patterns. The number of threatened taxa in this region is increasing rapidly and there is an urgent need for (sub-)species conservation in this region. Our study provides first genetic evidence for treating several island taxa as distinct species. In both species complexes similar genetic patterns were detected. Genetic diversification was higher across the islands of the Wallacea than across the islands of the Sahul Shelf. Divergence in E. roratus can be dated back about 1.38 million years ago, whereas in the younger T. haematodus it was 0.80 million years ago. Long distance dispersal was the most likely event for distribution patterns across the Wallacea and Sahul Shelf. The geographic origin of the species-complex Eclectus roratus spp. is supposed to be Wallacean, but for the species-complex Trichoglossus haematodus spp. it is supposed to be non-Wallacean. Trichoglossus euteles, so far considered a distinct species, clearly belongs to the Trichoglossus-haematodus-complex. The only case of sympatry in the complex is the distribution of T. (h.) euteles and T. h. capistratus on Timor, which means a rapid evolution from one ancestor into two distinct species within only 800,000 years. For all other taxa a Checkerboard distribution pattern is present. In this complex, 8 taxa are already treated as separate species (del Hoyo et al. 2014). Based on genetic evidence, the following populations are supported to represent phylogenetic units: (1) N New Guinea (haematodus) incl. Biak (rosenbergii), Bismarck Archipelago (massena), and New Caledonia (deplanchii); (2) Flores (weberi); (3) E Australia (moluccanus) incl. Aru Islands (nigrogularis) and S New Guinea (caeruleiceps); (4) N Australia (rubritorquis); (5) Timor 1st lineage (capistratus) incl. Sumba (fortis); (6) Bali and Lombok (mitchellii); (7) Sumbawa (forsteni); (8) Timor 2nd lineage (euteles). Those 8 phylogenetic units are not identical to the 8 species listed by del Hoyo et al. (2014). Several populations on smaller islands are under decline, a separate species status may lead to a higher conservation status in both species complexes, which are currently listed as “Least Concern”. Eclectus roratus is currently treated as monospecific. Based on genetic evidence, the following populations are suggested being treated as valid species: (1) Sumba (Eclectus cornelia), (2) Tanimbar Islands (E. riedeli), (3) Moluccas (E. roratus), and (4) New Guinea (E. polychloros incl. Aru Islands (E. aruensis), and Solomon Island (E. solomonensis).

Four new species of Phrynus, Lamarck (Arachnida: Amblypygi) from Mexico

Zootaxa ◽  
2021 ◽  
Vol 4948 (2) ◽  
pp. 151-183
Author(s):  
DANIEL CHIRIVI JOYA
Keyword(s):  
New Species ◽  
Species Complex ◽  
Population Studies ◽  
The Other ◽  
Genetic Population ◽  
Male And Female ◽  
Taxonomic Information ◽  
Species Complexes ◽  
Morphologic Variation ◽  
Mexican Species

Mexico is the country with the largest diversity of the genus Phrynus (Amblypygi: Phrynidae); however, many species could remain hidden due to the conservative morphology of the group. Two of the Mexican species, P. operculatus, and P. jalisco show enough variation, between populations from different localities, to be considered as possible species complexes. The scarce taxonomic information of these species and the few analyses of their variation could cause misidentifications and sub estimation of the diversity. Specimens morphologically similar to P. operculatus from different Mexican localities were analyzed, using characters from the male and female genitals. Four new species are described, presenting illustrations of SEM for the male genitals. Details of the morphologic variation in this group of species are discussed, as well as the usefulness of sexual characters like the size proportions, and sclerotization in the female gonopods, and ornaments in males, to improve the diagnoses of the Mexican Phrynus. The known distribution of P. operculatus is large in comparison with those of the other species, after the result of this research, the possibility that it is a larger species complex is evident, thus, it is necessary to increase the morphologic and genetic population studies in this group. 

scholarly journals Host-symbiont coevolution, cryptic structure, and bleaching susceptibility, in a coral species complex (Scleractinia; Poritidae)

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Z. H. Forsman ◽  
R. Ritson-Williams ◽  
K.H. Tisthammer ◽  
I. S. S. Knapp ◽  
R. J. Toonen
Keyword(s):  
Genetic Structure ◽  
Evolutionary Biology ◽  
Species Complex ◽  
Coral Species ◽  
Genetic Relationships ◽  
Level Variation ◽  
Reduced Representation ◽  
The Pacific ◽  
Rapid Diversification ◽  
Candidate Loci

Abstract The ‘species’ is a key concept for conservation and evolutionary biology, yet the lines between population and species-level variation are often blurred, especially for corals. The ‘Porites lobata species complex’ consists of branching and mounding corals that form reefs across the Pacific. We used reduced representation meta-genomic sequencing to examine genetic relationships within this species complex and to identify candidate loci associated with colony morphology, cryptic genetic structure, and apparent bleaching susceptibility. We compared existing Porites data with bleached and unbleached colonies of the branching coral P. compressa collected in Kāneʻohe Bay Hawaiʻi during the 2015 coral bleaching event. Loci that mapped to coral, symbiont, and microbial references revealed genetic structure consistent with recent host-symbiont co-evolution. Cryptic genetic clades were resolved that previous work has associated with distance from shore, but no genetic structure was associated with bleaching. We identified many candidate loci associated with morphospecies, including candidate host and symbiont loci with fixed differences between branching and mounding corals. We also found many loci associated with cryptic genetic structure, yet relatively few loci associated with bleaching. Recent host-symbiont co-evolution and rapid diversification suggests that variation and therefore the capacity of these corals to adapt may be underappreciated.

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