Cranial and post-cranial remains and phylogenetic relationships of the Gondwanan meiolaniform turtle Peligrochelys walshae from the Paleocene of Chubut, Argentina

2019 ◽  
Vol 93 (04) ◽  
pp. 798-821 ◽  
Author(s):  
Juliana Sterli ◽  
Marcelo S. de la Fuente
Keyword(s):  
Phylogenetic Analysis ◽  
3D Reconstruction ◽  
Early Cretaceous ◽  
Phylogenetic Relationships ◽  
Mass Extinction ◽  
Field Work ◽  
The Holocene ◽  
Previous Hypothesis ◽  
Postcranial Remains ◽  
Salamanca Formation

AbstractPeligrochelys walshae is a meiolaniform turtle originally described based on four specimens represented by cranial remains found in the classic locality of Punta Peligro (Chubut, Argentina) in outcrops of the Salamanca Formation (Danian). Recent field work in the vicinity of Punta Peligro resulted in the discovery of almost 30 new specimens, represented by cranial and postcranial remains that can be assigned to P. walshae. In this contribution, we provide a detailed anatomical description of the new specimens, provide an emended diagnosis for the species, and explore its phylogenetic relationships based on all anatomical data available for the species. The new specimens bring valuable information about the anatomy of the skull and postcranium of P. walshae as well as for meiolaniforms in general. The 3D preservation of the skull bones allows us to provide a 3D reconstruction using novel techniques. The updated phylogenetic analysis confirms that P. walshae is part of the clade Meiolaniformes, which spans from the Early Cretaceous until the Holocene and contains the giant, horned turtles (Meiolaniidae). This phylogenetic analysis reinforces the previous hypothesis that the clade Meiolaniformes is dominated by Gondwanan taxa, but also includes some Laurasian representatives. Alternate phylogenetic positions of taxa included in Meiolaniformes in this analysis were tested using the Templeton test. The lineage leading to Peligrochelys walshae is the only meiolaniform non-meiolaniid lineage to have survived the K-Pg mass extinction; its study provides valuable information to evaluate the effects of the K-Pg extinction in turtles.

scholarly journals Two Complete Mitochondrial Genomes of Mileewinae (Hemiptera: Cicadellidae) and a Phylogenetic Analysis

Insects ◽  
2021 ◽  
Vol 12 (8) ◽  
pp. 668
Author(s):  
Tinghao Yu ◽  
Yalin Zhang
Keyword(s):  
Phylogenetic Analysis ◽  
Phylogenetic Relationships ◽  
Phylogenetic Trees ◽  
Strong Support ◽  
Intergenic Spacer ◽  
Taxonomic Status ◽  
Start Codon ◽  
Gene Arrangement ◽  
Mitochondrial Genomes ◽  
Protein Coding

More studies are using mitochondrial genomes of insects to explore the sequence variability, evolutionary traits, monophyly of groups and phylogenetic relationships. Controversies remain on the classification of the Mileewinae and the phylogenetic relationships between Mileewinae and other subfamilies remain ambiguous. In this study, we present two newly completed mitogenomes of Mileewinae (Mileewa rufivena Cai and Kuoh 1997 and Ujna puerana Yang and Meng 2010) and conduct comparative mitogenomic analyses based on several different factors. These species have quite similar features, including their nucleotide content, codon usage of protein genes and the secondary structure of tRNA. Gene arrangement is identical and conserved, the same as the putative ancestral pattern of insects. All protein-coding genes of U. puerana began with the start codon ATN, while 5 Mileewa species had the abnormal initiation codon TTG in ND5 and ATP8. Moreover, M. rufivena had an intergenic spacer of 17 bp that could not be found in other mileewine species. Phylogenetic analysis based on three datasets (PCG123, PCG12 and AA) with two methods (maximum likelihood and Bayesian inference) recovered the Mileewinae as a monophyletic group with strong support values. All results in our study indicate that Mileewinae has a closer phylogenetic relationship to Typhlocybinae compared to Cicadellinae. Additionally, six species within Mileewini revealed the relationship (U. puerana + (M. ponta + (M. rufivena + M. alara) + (M. albovittata + M. margheritae))) in most of our phylogenetic trees. These results contribute to the study of the taxonomic status and phylogenetic relationships of Mileewinae.

Phylogenetic analysis of the subfamily Hylodinae (Anura, Leptodactylidae) based on morphological characters

2005 ◽  
Vol 26 (2) ◽  
pp. 139-147 ◽  
Author(s):  
Francisca do Val ◽  
Paulo Nuin
Keyword(s):  
Phylogenetic Analysis ◽  
Phylogenetic Relationships ◽  
Maximum Parsimony ◽  
Morphological Characters ◽  
The Other ◽  
The Family

AbstractThe systematics and phylogenetic relationships of the family Leptodactylidae are controversial as is the intrafamilial phylogeny of the leptodactylids. Here we analyze the relationships of the leptodactylid subfamily Hylodinae. This subfamily has been considered to be monophyletic and composed of three genera, Hylodes, Crossodactylus and Megaelosia. In the present study 49 characters were used, based on different studies on Leptodactylidae phylogeny. Maximum parsimony methods with unweighted and successively weighted characters were used to estimate the phylogeny of the Hylodinae. Upon analysis, the data provided further evidence of the monophyletic status of the three genera, with Megaelosia being the basal genus and the other two genera being sister taxa. The analysis with successive weighting results in a more resolved topology of the species subgroups of the genus Hylodes and separates this genus from Crossodactylus and confirms that the hylodines are monophyletic.

scholarly journals New interpretation of the cranial osteology of the Early Cretaceous turtle Arundelemys dardeni (Paracryptodira) based on a CT-based re-evaluation of the holotype

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11495
Author(s):  
Serjoscha W. Evers ◽  
Yann Rollot ◽  
Walter G. Joyce
Keyword(s):  
Early Cretaceous ◽  
Computer Tomography ◽  
Mass Extinction ◽  
Early Evolution ◽  
New Interpretation ◽  
Phylogenetic Hypotheses ◽  
Initial Description ◽  
Cranial Osteology ◽  
Anatomical Information

Arundelemys dardeni is an Early Cretaceous paracryptodire known from a single, incomplete, but generally well-preserved skull. Phylogenetic hypotheses of paracryptodires often find Arundelemys dardeni as an early branching baenid. As such, it has a central role in understanding the early evolution of the successful clade Baenidae, which survived the Cretaceous–Paleogene mass extinction, as well as the diversification of Paracryptodira into its subclades, which recent research suggests to perhaps include helochelydrids, compsemydids, pleurosternids, and baenids. Computer tomography scans of the holotype material that were produced for the initial description of Arundelemeys dardeni reveal several errors in the initial anatomical description of the species, which we correct based on element-by-element segmentation. In addition, we provide entirely novel anatomical information, including descriptions of several previously undescribed cranial bones, the endosseous labyrinth, and the cranial scutes, the latter of which are unknown for most paracryptodires. We provide an interpretation of cranial scutes which homologizes the scutes of Arundelemys dardeni with those of other stem turtles.

scholarly journals Insight on the anatomy, systematic relationships, and age of the Early Cretaceous ankylopollexian dinosaur Dakotadon lakotaensis

2015 ◽  
Author(s):  
Clint A Boyd ◽  
Darrin C Pagnac
Keyword(s):  
Early Cretaceous ◽  
Original Description ◽  
Field Work ◽  
Optimality Criteria ◽  
Dorsal Vertebra ◽  
The Past ◽  
Caudal Vertebrae ◽  
Systematic Relationships ◽  
Preparation Work ◽  
Extensive Deformation

Knowledge regarding the early evolution within the dinosaurian clade Ankylopollexia drastically increased over the past two decades, in part because of an increase in described taxa from the Early Cretaceous of North America. These advances motivated the recent completion of extensive preparation and conservation work on the holotype and only known specimen of Dakotadon lakotaensis, a basal ankylopollexian from the Lakota Formation of South Dakota. That specimen (SDSM 8656) preserves a partial skull, lower jaws, a single dorsal vertebra, and two caudal vertebrae. That new preparation work exposed several bones not included in the original description and revealed that other bones were previously misidentified. The presence of extensive deformation in areas of the skull is also noted that influenced inaccuracies in prior descriptions and reconstructions of this taxon. In addition to providing an extensive re-description of D. lakotaensis, this study reviews previously proposed diagnoses for this taxon, identifies two autapomorphies, and provides an extensive differential diagnosis. Dakotadon lakotaensis is distinct from the only other ankylopollexian taxon known from the Lakota Formation, Osmakasaurus depressus, in the presence of two prominent, anteroposteriorly oriented ridges on the ventral surfaces of the caudal vertebrae, the only overlapping material preserved between these taxa. The systematic relationships of D. lakotaensis are evaluated using both the parsimony and posterior probability optimality criteria, with both sets of analyses recovering D. lakotaensis as a non-hadrosauriform ankylopollexian that is more closely related to taxa from the Early Cretaceous (e.g., Iguanacolossus, Hippodraco, and Theiophytalia) than to more basally situated taxa from the Jurassic (e.g., Camptosaurus, Uteodon). This taxonomic work is supplemented by field work that relocated the type locality, confirming its provenance from unit L2 (lower Fuson Member equivalent) of the Lakota Formation. Those data, combined with recently revised ages for the members of the Lakota Formation based on charophyte and ostracod biostratigraphy, constrain the age of this taxon to the late Valanginian to early Barremian.

scholarly journals Eutherians experienced elevated evolutionary rates in the immediate aftermath of the Cretaceous–Palaeogene mass extinction

2016 ◽  
Vol 283 (1833) ◽  
pp. 20153026 ◽  
Author(s):  
Thomas John Dixon Halliday ◽  
Paul Upchurch ◽  
Anjali Goswami
Keyword(s):  
Phylogenetic Analysis ◽  
Adaptive Radiation ◽  
Mass Extinction ◽  
Fossil Record ◽  
Morphological Evolution ◽  
Placental Mammal ◽  
Stochastic Methods ◽  
Ecological Niches ◽  
Evolutionary Radiation ◽  
Quantitative Analyses

The effect of the Cretaceous–Palaeogene (K–Pg) mass extinction on the evolution of many groups, including placental mammals, has been hotly debated. The fossil record suggests a sudden adaptive radiation of placentals immediately after the event, but several recent quantitative analyses have reconstructed no significant increase in either clade origination rates or rates of character evolution in the Palaeocene. Here we use stochastic methods to date a recent phylogenetic analysis of Cretaceous and Palaeocene mammals and show that Placentalia likely originated in the Late Cretaceous, but that most intraordinal diversification occurred during the earliest Palaeocene. This analysis reconstructs fewer than 10 placental mammal lineages crossing the K–Pg boundary. Moreover, we show that rates of morphological evolution in the 5 Myr interval immediately after the K–Pg mass extinction are three times higher than background rates during the Cretaceous. These results suggest that the K–Pg mass extinction had a marked impact on placental mammal diversification, supporting the view that an evolutionary radiation occurred as placental lineages invaded new ecological niches during the Early Palaeocene.

Albumin Immunological Relationships of Australian Marsupials. 2. The Pseudocheiridae

1990 ◽  
Vol 38 (5) ◽  
pp. 519 ◽  
Author(s):  
PR Baverstock ◽  
M Krieg ◽  
J Birrell ◽  
GM Mckay
Keyword(s):  
Phylogenetic Analysis ◽  
Phylogenetic Relationships ◽  
Phylogenetic Position ◽  
The Family ◽  
Microcomplement Fixation

Microcomplement fixation of albumin was used to examine the phylogenetic relationships among the ringtail possums, family Pseudocheiridae. Phylogenetic analysis of the data supports the hypothesis of at least three distinct clades within the family: one containing Petauroides and Hemibelideus; a second consisting of Pseudocheirus herbertensis, Ps. forbesi, Ps. mayeri, and Ps. canescens; and a third containing Ps. archeri, Ps. corinnae, Ps. cupreus and Ps. dahli. The data have not resolved the phylogenetic position of Ps. peregrinus, which may either form a separate clade or lie close to the Ps. archeri clade.

Systematics of a survivor: the Cambrian kingstoniid trilobite Blountia Walcott, 1916 across the Marjuman–Steptoean (Guzhangian–Paibian) extinction interval in Laurentian North America

Zootaxa ◽  
2020 ◽  
Vol 4804 (1) ◽  
pp. 1-79
Author(s):  
MADISON ARMSTRONG ◽  
STEPHEN R. WESTROP ◽  
JENNIFER D. EOFF
Keyword(s):  
Phylogenetic Analysis ◽  
New Species ◽  
North America ◽  
Mass Extinction ◽  
Archival Material ◽  
Number Of Species

The Cambrian (Marjuman–Steptoean; Guzhangian–Paibian) kingstoniid trilobite Blountia Walcott, 1916 is distributed widely in shelf strata of Laurentian North America. Species known from Marjuman formations were lost at the mass extinction at the end of that stage. New species entered the succession during and after the extinction interval, only to disappear within the Aphelaspis Zone of the lower part of the Steptoean Stage. Steptoean species and several uppermost Marjuman (Crepicephalus Zone) species are treated in this monograph. New collections and revision of type and other archival material increase the number of species in Steptoean strata from two to six. Phylogenetic analysis supports monophyly of Blountia and Maryvillia Walcott, 1916; Blountina Lochman, in Lochman & Duncan, 1944 is retained as a monotypic taxon. Steptoean species do not form a single subclade within the cladogram, so there is no evidence for a simple monophyletic radiation following the end-Marjuman extinction. New species are Blountia angelae, B. morgancreekensis, B. nevadensis, B. newfoundlandensis, and B. tennesseensis. 

scholarly journals Taxonomic revision and phylogenetic relationships of Dasyloricaria Isbrücker & Nijssen, 1979 (Siluriformes: Loricariidae), with description of a new species

2016 ◽  
Vol 14 (1) ◽  
Author(s):  
Alejandro Londoño-Burbano ◽  
Roberto E. Reis
Keyword(s):  
Phylogenetic Analysis ◽  
New Species ◽  
Phylogenetic Relationships ◽  
Taxonomic Revision ◽  
Sister Group ◽  
Valid Species ◽  
Maracaibo Basin ◽  
New Synonyms ◽  
Branchial Arches ◽  
A New Species

ABSTRACT A taxonomic revision and phylogenetic analysis were completed for Dasyloricaria . The genus includes three valid species: D . filamentosa and D . latiura previously included in the genus, and a new species described herein. Dasyloricaria have a restricted trans-Andean distribution, with D . filamentosa occurring at the lower and middle Magdalena, lower Cauca, and Sinu in Colombia, and lago Maracaibo basin in Colombia and Venezuela; D . latiura in the Atrato and the Tuyra basins in Colombia and Panama, respectively; and the new species in the upper and middle Magdalena basin in Colombia. New synonyms for D . filamentosa and D . latiura are proposed, and a lectotype is designated for the latter. Dasyloricaria is herein recognized as monophyletic, with D . filamentosa as the sister group of D . latiura , and the new speciesas sister to that clade. Spatuloricaria is hypothesized to be the sister group of Dasyloricaria based on synapomorphies of the neurocranium, branchial arches and external morphology features. The subtribe Rineloricariina was partially corroborated through the phylogenetic analysis. An identification key for the species of Dasyloricaria is provided.

Reappraisal of arctostylopid mammal Kazachostylops occidentalis from the late Paleocene of Kazakhstan and phylogenetic relationships within Arctostylopida

2019 ◽  
Vol 94 (3) ◽  
pp. 568-579
Author(s):  
Alexander O. Averianov
Keyword(s):  
Phylogenetic Analysis ◽  
North American ◽  
Phylogenetic Relationships ◽  
New Genus ◽  
Principal Component ◽  
Sister Taxon ◽  
Phylogenetic Hypothesis ◽  
Lower Eocene ◽  
Principal Component Analyses ◽  
Upper Paleocene

AbstractKazachostylops occidentalis Nesov, 1987b, based on partial maxilla and dentary from the upper Paleocene Zhylga locality in South Kazakhstan, is redescribed. A new phylogenetic hypothesis of Arctostylopida is proposed based on phylogenetic analysis of 26 characters and 17 taxa. Kazachostylops is recovered as a sister taxon to the Arctostylopinae, the advanced clade of Asian and North American arctostylopids characterized by pseudohypocone on upper molars and reduced trigonid of lower molars, with the ectolophid being attached labial on the trigonid. Kazachostylops differs from more basal arctostylopids (Asiostylops, Allostylops, Bothriostylops, and Wanostylops) by higher-crowned molars, M1–3 metaconule absent, m1–3 entoconid connected with ectolophid by entolophid, and m2 wider than m1 and m3. Principal component analyses of the upper and lower dentition of arctostylopids show great distinctness of Kazachostylops from other members of the group. The arctostylopid taxa are reviewed, and the new genus Enantiostylops is erected for ‘Sinostylops’ progressus Tang and Yan, 1976 from the lower Eocene of China, because of uniquely concave parastylar area on upper molars.UUID: http://zoobank.org/a46d8f29-fd73-4e59-88dc-fcc55b12d1d3

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