scholarly journals Phylogenetic systematics and evolution of the spider infraorder Mygalomorphae using genomic scale data

2019 ◽  
Author(s):  
Vera Opatova ◽  
Chris A. Hamilton ◽  
Marshal Hedin ◽  
Laura Montes de Oca ◽  
Jiří Král ◽  
...  
Keyword(s):  
Divergence Time ◽  
Wide Distribution ◽  
Nominal Species ◽  
Generic Level ◽  
Divergence Time Estimates ◽  
New Family ◽  
Time Estimates ◽  
Generic Composition ◽  
Anchored Hybrid Enrichment ◽  
Genomic Scale

AbstractThe Infraorder Mygalomorphae is one of the three main lineages of spiders comprising over 3,000 nominal species. This ancient group has a world-wide distribution that includes among its ranks large and charismatic taxa such as tarantulas, trapdoor spiders, and highly venomous funnel web spiders. Based on past molecular studies using Sanger-sequencing approaches, numerous mygalomorph families (e.g., Hexathelidae, Ctenizidae, Cyrtaucheniidae, Dipluridae and Nemesiidae) have been identified as non-monophyletic. However, these data were unable to sufficiently resolve the higher-level (intra- and interfamilial) relationships such that the necessary changes in classification could be made with confidence. Here we present the most comprehensive phylogenomic treatment of the spider infraorder Mygalomorphae conducted to date. We employ 472 loci obtained through Anchored Hybrid Enrichment to reconstruct relationships among all the mygalomorph spider families and estimate the timeframe of their diversification. We performed an extensive generic sampling of all currently recognized families, which has allowed us to assess their status, and as a result, propose a new classification scheme. Our generic-level sampling has also provided an evolutionary framework for revisiting questions regarding silk use in mygalomorph spiders. The first such analysis for the group within a strict phylogenetic framework shows that a sheet web is likely the plesiomorphic condition for mygalomorphs, as well as providing hints to the ancestral foraging behavior for all spiders. Our divergence time estimates, concomitant with detailed biogeographic analysis, suggest that both ancient continental-level vicariance and more recent dispersal events have played an important role in shaping modern day distributional patterns. Based on our results, we relimit the generic composition of the Ctenizidae, Cyrtaucheniidae, Dipluridae and Nemesiidae. We also elevate five subfamilies to family rank: Anamidae (NEW RANK), Euagridae (NEW RANK), Ischnothelidae (NEW RANK), Pycnothelidae (NEW RANK), and Bemmeridae (NEW RANK). The three families Hermachidae (NEW FAMILY), Microhexuridae (NEW FAMILY), and Stasimopidae (NEW FAMILY) are newly proposed. Such a major rearrangement in classification, recognizing eight newly established family-level rank taxa, is the largest the group has seen in over three decades since Raven’s (1985) taxonomic treatment.

scholarly journals Phylogenetic Systematics and Evolution of the Spider Infraorder Mygalomorphae Using Genomic Scale Data

2019 ◽  
Vol 69 (4) ◽  
pp. 671-707 ◽  
Author(s):  
Vera Opatova ◽  
Chris A Hamilton ◽  
Marshal Hedin ◽  
Laura Montes De Oca ◽  
Jiři Král ◽  
...  
Keyword(s):  
Divergence Time ◽  
Molecular Clocks ◽  
Nominal Species ◽  
Generic Level ◽  
Spider Web ◽  
Divergence Time Estimates ◽  
Worldwide Distribution ◽  
New Family ◽  
Generic Composition ◽  
Anchored Hybrid Enrichment

Abstract The infraorder Mygalomorphae is one of the three main lineages of spiders comprising over 3000 nominal species. This ancient group has a worldwide distribution that includes among its ranks large and charismatic taxa such as tarantulas, trapdoor spiders, and highly venomous funnel-web spiders. Based on past molecular studies using Sanger-sequencing approaches, numerous mygalomorph families (e.g., Hexathelidae, Ctenizidae, Cyrtaucheniidae, Dipluridae, and Nemesiidae) have been identified as non-monophyletic. However, these data were unable to sufficiently resolve the higher-level (intra- and interfamilial) relationships such that the necessary changes in classification could be made with confidence. Here, we present a comprehensive phylogenomic treatment of the spider infraorder Mygalomorphae. We employ 472 loci obtained through anchored hybrid enrichment to reconstruct relationships among all the mygalomorph spider families and estimate the timeframe of their diversification. We sampled nearly all currently recognized families, which has allowed us to assess their status, and as a result, propose a new classification scheme. Our generic-level sampling has also provided an evolutionary framework for revisiting questions regarding silk use in mygalomorph spiders. The first such analysis for the group within a strict phylogenetic framework shows that a sheet web is likely the plesiomorphic condition for mygalomorphs, as well as providing insights to the ancestral foraging behavior for all spiders. Our divergence time estimates, concomitant with detailed biogeographic analysis, suggest that both ancient continental-level vicariance and more recent dispersal events have played an important role in shaping modern day distributional patterns. Based on our results, we relimit the generic composition of the Ctenizidae, Cyrtaucheniidae, Dipluridae, and Nemesiidae. We also elevate five subfamilies to family rank: Anamidae (NEW RANK), Euagridae (NEW RANK), Ischnothelidae (NEW RANK), Pycnothelidae (NEW RANK), and Bemmeridae (NEW RANK). Three families Entypesidae (NEW FAMILY), Microhexuridae (NEW FAMILY), and Stasimopidae (NEW FAMILY), and one subfamily Australothelinae (NEW SUBFAMILY) are newly proposed. Such a major rearrangement in classification, recognizing nine newly established family-level rank taxa, is the largest the group has seen in over three decades. [Biogeography; molecular clocks; phylogenomics; spider web foraging; taxonomy.]

scholarly journals Phylogenetic relationships of the cuscuses (Diprotodontia : Phalangeridae) of island Southeast Asia and Melanesia based on the mitochondrial ND2 gene

2020 ◽  
Vol 42 (3) ◽  
pp. 266 ◽  
Author(s):  
Shimona Kealy ◽  
Stephen C. Donnellan ◽  
Kieren J. Mitchell ◽  
Michael Herrera ◽  
Ken Aplin ◽  
...  
Keyword(s):  
Dna Sequences ◽  
Divergence Time ◽  
Taxonomic Status ◽  
Wide Distribution ◽  
Species Level ◽  
Source Population ◽  
Divergence Time Estimates ◽  
Time Estimates ◽  
Multiple Species ◽  
Nd2 Gene

The species-level systematics of the marsupial family Phalangeridae, particularly Phalanger, are poorly understood, due partly to the family’s wide distribution across Australia, New Guinea, eastern Indonesia, and surrounding islands. In order to refine the species-level systematics of Phalangeridae, and improve our understanding of their evolution, we generated 36 mitochondrial ND2 DNA sequences from multiple species and sample localities. We combined our new data with available sequences and produced the most comprehensive molecular phylogeny for Phalangeridae to date. Our analyses (1) strongly support the monophyly of the three phalangerid subfamilies (Trichosurinae, Ailuropinae, Phalangerinae); (2) reveal the need to re-examine all specimens currently identified as ‘Phalanger orientalis’; and (3) suggest the elevation of the Solomon Island P. orientalis subspecies to species level (P. breviceps Thomas, 1888). In addition, samples of P. orientalis from Timor formed a clade, consistent with an introduction by humans from a single source population. However, further research on east Indonesian P. orientalis populations will be required to test this hypothesis, resolve inconsistencies in divergence time estimates, and locate the source population and taxonomic status of the Timor P. orientalis.

scholarly journals Taxonomy, Phylogeny, Molecular Dating and Ancestral State Reconstruction of Xylariomycetidae (Sordariomycetes)

2021 ◽  
Author(s):  
Milan C. Samarakoon ◽  
Kevin D Hyde ◽  
Sajeewa S. N. Maharachchikumbura ◽  
Marc Stadler ◽  
E. B. Gareth Jones ◽  
...  
Keyword(s):  
Divergence Time ◽  
Molecular Dating ◽  
Character State ◽  
Ancestral State ◽  
New Host ◽  
State Reconstruction ◽  
Divergence Time Estimates ◽  
New Family ◽  
Ancestral Character State ◽  
Time Estimates

Abstract Xylariomycetidae ( Ascomycota ) is a highly diversified group with variable stromatic characters. Our research focused on inconspicuous stromatic xylarialean taxa from China, Italy, Russia, Thailand and the United Kingdom. Detailed morphological descriptions, illustrations and combined ITS-LSU- rpb 2- tub 2- tef 1 phylogenies revealed 38 taxa from our collections belonging to Amphisphaeriales and Xylariales . A new family ( Appendicosporaceae ), five new genera ( Magnostiolata , Melanostictus , Neoamphisphaeria , Nigropunctata and Paravamsapriya ), 27 new species ( Acrocordiella photiniicola , Allocryptovalsa sichuanensis , Amphisphaeria parvispora , Anthostomella lamiacearum , Apiospora guiyangensis , Ap. sichuanensis , Biscogniauxia magna , Eutypa camelliae , Helicogermslita clypeata , Hypocopra zeae , Magnostiolata mucida , Melanostictus longiostiolatus , Me. thailandicus , Nemania longipedicellata , Ne. delonicis , Ne. paraphysata , Ne. thailandensis , Neoamphisphaeria hyalinospora , Neoanthostomella bambusicola , Nigropunctata bambusicola , Ni. nigrocircularis , Ni. thailandica , Occultitheca rosae , Paravamsapriya ostiolata , Peroneutypa leucaenae , Seiridium italicum and Vamsapriya mucosa ) and seven new host/geographical records are introduced and reported. Divergence time estimates indicate that Delonicicolales diverged from Amphisphaeriales + Xylariales at 161 (123–197) MYA. Amphisphaeriales and Xylariales diverged 154 (117–190) MYA with a crown age of 127 (92–165) MYA and 147 (111–184) MYA, respectively. Appendicosporaceae ( Amphisphaeriales ) has a stem age of 89 (65–117) MYA. Ancestral character state reconstruction indicates that astromatic, clypeate ascomata with aseptate, hyaline ascospores that lack germ slits may probably be ancestral Xylariomycetidae having plant-fungal endophytic associations. The Amphisphaeriales remained mostly astromatic with common septate, hyaline ascospores. Stromatic variations may have developed mostly during the Cretaceous period. Brown ascospores are common in Xylariales , but they first appeared in Amphisphaeriaceae , Melogrammataceae and Sporocadaceae during the early Cretaceous. The ascospore germ slits appeared only in Xylariales during the Cretaceous after the divergence of Lopadostomataceae . Hyaline, filiform and apiospores may have appeared as separate lineages providing the basis to Xylariaceae , which may have diverged independently. The future classification of polyphyletic xylarialean taxa will not be based on stromatic variations, but the type of ring, the colour of the ascospores, and the presence or absence of the type of germ slit.

scholarly journals Integrating Different Lines of Evidence to Establish a Novel Ascomycete Genus and Family (Anastomitrabeculia, Anastomitrabeculiaceae) in Pleosporales

2021 ◽  
Vol 7 (2) ◽  
pp. 94
Author(s):  
Chitrabhanu S. Bhunjun ◽  
Chayanard Phukhamsakda ◽  
Rajesh Jeewon ◽  
Itthayakorn Promputtha ◽  
Kevin D. Hyde
Keyword(s):  
Phylogenetic Analyses ◽  
Divergence Time ◽  
Distinct Species ◽  
Divergence Time Estimates ◽  
New Family ◽  
Time Estimates ◽  
The Family ◽  
Freshwater Stream ◽  
Cretaceous Period ◽  
Lines Of Evidence

A novel genus, Anastomitrabeculia, is introduced herein for a distinct species, Anastomitrabeculia didymospora, collected as a saprobe on dead bamboo culms from a freshwater stream in Thailand. Anastomitrabeculia is distinct in its trabeculate pseudoparaphyses and ascospores with longitudinally striate wall ornamentation. A new family, Anastomitrabeculiaceae, is introduced to accommodate Anastomitrabeculia. Anastomitrabeculiaceae forms an independent lineage basal to Halojulellaceae in Pleosporales and it is closely related to Neohendersoniaceae based on phylogenetic analyses of a combined LSU, SSU and TEF1α dataset. In addition, divergence time estimates provide further support for the establishment of Anastomitrabeculiaceae. The family diverged around 84 million years ago (MYA) during the Cretaceous period, which supports the establishment of the new family. The crown and stem age of Anastomitrabeculiaceae was also compared to morphologically similar pleosporalean families.

Molecular phylogeny and divergence time estimates of Penaeid Shrimp Lineages (Decapoda: Penaeidae)

Zootaxa ◽  
2009 ◽  
Vol 2107 (1) ◽  
pp. 41-52 ◽  
Author(s):  
CAROLINA M VOLOCH ◽  
PABLO R FREIRE ◽  
CLAUDIA A M RUSSO
Keyword(s):  
Fossil Record ◽  
Divergence Time ◽  
Penaeid Shrimp ◽  
Divergence Time Estimates ◽  
Time Estimates ◽  
Global Clock ◽  
Late Tertiary ◽  
The Family ◽  
Molecular Studies ◽  
Triassic Period

Fossil record of penaeids indicates that the family exists since the Triassic period, but extant genera appeared only recently in Tertiary strata. Molecular based divergence time estimates on the matter of penaeid radiation were never properly addressed, due to shortcomings of the global molecular clock assumptions. Here, we studied the diversification patterns of the family, uncovering, more specifically, a correlation between fossil and extant Penaeid fauna. For this, we have used a Bayesian framework that does not assume a global clock. Our results suggest that Penaeid genera originated between 20 million years ago and 43 million years ago, much earlier than expected by previous molecular studies. Altogether, these results promptly discard late Tertiary or even Quaternary hypotheses that presumed a major glaciations influence on the diversification patterns of the family.

scholarly journals Out of the Neotropics: Late Cretaceous colonization of Australasia by American arthropods

2012 ◽  
Vol 279 (1742) ◽  
pp. 3501-3509 ◽  
Author(s):  
Prashant P. Sharma ◽  
Gonzalo Giribet
Keyword(s):  
Late Cretaceous ◽  
Divergence Time ◽  
Disjunct Distribution ◽  
Continental Margins ◽  
Divergence Time Estimates ◽  
Evolutionary Origins ◽  
Source Regions ◽  
Time Estimates ◽  
Fiji Islands ◽  
The Pacific

The origins of tropical southwest Pacific diversity are traditionally attributed to southeast Asia or Australia. Oceanic and fragment islands are typically colonized by lineages from adjacent continental margins, resulting in attrition of diversity with distance from the mainland. Here, we show that an exceptional tropical family of harvestmen with a trans-Pacific disjunct distribution has its origin in the Neotropics. We found in a multi-locus phylogenetic analysis that the opilionid family Zalmoxidae, which is distributed in tropical forests on both sides of the Pacific, is a monophyletic entity with basal lineages endemic to Amazonia and Mesoamerica. Indo-Pacific Zalmoxidae constitute a nested clade, indicating a single colonization event. Lineages endemic to putative source regions, including Australia and New Guinea, constitute derived groups. Divergence time estimates and probabilistic ancestral area reconstructions support a Neotropical origin of the group, and a Late Cretaceous ( ca 82 Ma) colonization of Australasia out of the Fiji Islands and/or Borneo, which are consistent with a transoceanic dispersal event. Our results suggest that the endemic diversity within traditionally defined zoogeographic boundaries might have more complex evolutionary origins than previously envisioned.

scholarly journals Using a GTR+Γ substitution model for dating sequence divergence when stationarity and time-reversibility assumptions are violated

2020 ◽  
Vol 36 (Supplement_2) ◽  
pp. i884-i894
Author(s):  
Jose Barba-Montoya ◽  
Qiqing Tao ◽  
Sudhir Kumar
Keyword(s):  
Divergence Time ◽  
Sequence Divergence ◽  
Molecular Dating ◽  
Divergence Times ◽  
Time Reversibility ◽  
Sequence Alignments ◽  
Divergence Time Estimates ◽  
Time Estimates ◽  
Substitution Process ◽  
The Impact

Abstract Motivation As the number and diversity of species and genes grow in contemporary datasets, two common assumptions made in all molecular dating methods, namely the time-reversibility and stationarity of the substitution process, become untenable. No software tools for molecular dating allow researchers to relax these two assumptions in their data analyses. Frequently the same General Time Reversible (GTR) model across lineages along with a gamma (+Γ) distributed rates across sites is used in relaxed clock analyses, which assumes time-reversibility and stationarity of the substitution process. Many reports have quantified the impact of violations of these underlying assumptions on molecular phylogeny, but none have systematically analyzed their impact on divergence time estimates. Results We quantified the bias on time estimates that resulted from using the GTR + Γ model for the analysis of computer-simulated nucleotide sequence alignments that were evolved with non-stationary (NS) and non-reversible (NR) substitution models. We tested Bayesian and RelTime approaches that do not require a molecular clock for estimating divergence times. Divergence times obtained using a GTR + Γ model differed only slightly (∼3% on average) from the expected times for NR datasets, but the difference was larger for NS datasets (∼10% on average). The use of only a few calibrations reduced these biases considerably (∼5%). Confidence and credibility intervals from GTR + Γ analysis usually contained correct times. Therefore, the bias introduced by the use of the GTR + Γ model to analyze datasets, in which the time-reversibility and stationarity assumptions are violated, is likely not large and can be reduced by applying multiple calibrations. Availability and implementation All datasets are deposited in Figshare: https://doi.org/10.6084/m9.figshare.12594638.

scholarly journals Morphological and molecular phylogenetic analyses of Zepedanulus ishikawai (Arachnida: Opiliones: Laniatores: Epedanidae) in the southern part of the Ryukyu Archipelago

2021 ◽  
pp. 1-28
Author(s):  
Yoshimasa Kumekawa ◽  
Haruka Fujimoto ◽  
Osamu Miura ◽  
Ryo Arakawa ◽  
Jun Yokoyama ◽  
...  
Keyword(s):  
Phylogenetic Tree ◽  
Phylogenetic Analyses ◽  
Divergence Time ◽  
Morphological Characters ◽  
Ryukyu Archipelago ◽  
Divergence Time Estimates ◽  
Time Estimates ◽  
Molecular Phylogenetic ◽  
History Of ◽  
Polymerase Chain

Abstract Harvestmen (Arachnida: Opiliones) are soil animals with extremely low dispersal abilities that experienced allopatric differentiation. To clarify the morphological and phylogenetic differentiation of the endemic harvestman Zepedanulus ishikawai (Suzuki, 1971) (Laniatores: Epedanidae) in the southern part of the Ryukyu Archipelago, we conducted molecular phylogenetic analyses and divergence time estimates based on CO1 and 16S rRNA sequences of mtDNA, the 28S rRNA sequence of nrDNA, and the external morphology. A phylogenetic tree based on mtDNA sequences indicated that individuals of Z. ishikawai were monophyletic and were divided into clade I and clade II. This was supported by the nrDNA phylogenetic tree. Although clades I and II were distributed sympatrically on all three islands examined (Ishigaki, Iriomote, and Yonaguni), heterogeneity could not be detected by polymerase chain reaction–restriction fragment length polymorphism of nrDNA, indicating that clades I and II do not have a history of hybridisation. Also, several morphological characters differed significantly between individuals of clade I and clade II. The longstanding isolation of the southern Ryukyus from the surrounding islands enabled estimation of the original morphological characters of both clades of Z. ishikawai.

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