scholarly journals Testing pterosaur ingroup relationships through broader sampling of avemetatarsalian taxa and characters and a range of phylogenetic analysis techniques

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e9604
Author(s):  
Matthew G. Baron
Keyword(s):  
Phylogenetic Analysis ◽  
Fossil Record ◽  
Phylogenetic Analyses ◽  
Sensu Stricto ◽  
Late Triassic ◽  
Sister Taxon ◽  
Analysis Techniques ◽  
Close Relationship ◽  
Anatomical Characters ◽  
First Time

The pterosaurs first appear in the fossil record in the middle of the Late Triassic. Their earliest representatives are known from Northern Hemisphere localities but, by the end of the Jurassic Period, this clade of flying reptiles achieved a global distribution, as well as high levels of diversity and disparity. Our understanding of early pterosaur evolution and the fundamental interrelationships within Pterosauria has improved dramatically in recent decades. However, there is still debate about how the various pterosaur subgroups relate to one another and about which taxa comprise these. Many recent phylogenetic analyses, while sampling well from among the known Triassic and Early Jurassic pterosaurs, have not included many non-pterosaurian ornithodirans or other avemetatarsalians. Given the close relationship between these groups of archosaurs, the omission of other ornithodirans and avemetatarsalians has the potential to adversely affect the results of phylogenetic analyses, in terms of character optimisation and ingroup relationships recovered. This study has addressed this issue and tests the relationships between the early diverging pterosaur taxa following the addition of avemetatarsalian taxa and anatomical characters to an existing early pterosaur dataset. This study has, for the first time, included taxa that represent the aphanosaurs, lagerpetids, silesaurids and dinosaurs, in addition to early pterosaurs. Anatomical characters used in other recent studies of archosaurs and early dinosaurs have also been incorporated. By expanding the outgroup taxa and anatomical character coverage in this pterosaur dataset, better resolution between the taxa within certain early pterosaur subclades has been achieved and stronger support for some existing clades has been found; other purported clades of early pterosaurs have not been found in this analysis—for example there is no support for a monophyletic Eopterosauria or Eudimorphodontidae. Further support has been found for a sister-taxon relationship between Peteinosaurus zambelli and Macronychoptera, a clade here named Zambellisauria (clade nov.), as well as for a monophyletic and early diverging Preondactylia. Some analyses also support the existence of a clade that falls as sister-taxon to the zambellisaurs, here named Caviramidae (clade nov.). Furthermore, some support has been found for a monophyletic Austriadraconidae at the base of Pterosauria. Somewhat surprisingly, Lagerpetidae is recovered outside of Ornithodira sensu stricto, meaning that, based upon current definitions at least, pterosaurs fall within Dinosauromorpha in this analysis. However, fundamental ornithodiran interrelationships were not the focus of this study and this particular result should be treated with caution for now. However, these results do further highlight the need for broader taxon and character sampling in phylogenetic analyses, and the effects of outgroup choice on determining ingroup relationships.

Venation pattern and revision of Orthoptera sensu nov. and sister groups. Phylogeny of Palaeozoic and Mesozoic Orthoptera sensu nov.

Zootaxa ◽  
2002 ◽  
Vol 96 (1) ◽  
pp. 1 ◽  
Author(s):  
OLIVIER BÉTHOUX ◽  
ANDRÉ NEL
Keyword(s):  
Phylogenetic Analysis ◽  
Fossil Record ◽  
Phylogenetic Analyses ◽  
Wing Venation ◽  
Venation Pattern ◽  
Biodiversity Crisis ◽  
Paraphyletic Group ◽  
New Interpretation ◽  
Orthopteroid Insects ◽  
First Time

After the revision of several fossils and observations of recent taxa, we propose a new interpretation of the wing venation pattern for the ‘orthopteroid lineage’. The Orthoptera and several taxa previously assigned to the paraphyletic group ‘Protorthoptera’ are included in a common clade, Archaeorthoptera taxon nov. The Orthoptera and some closest relative groups are included in the Panorthoptera sensu nov. These assignments are based on new autapomorphies based on venation patterns. A cladistic phylogenetic analysis of the Orthoptera is performed for the first time on the fossil record of this group, based on 74 characters (131 informative states). Three taxa assigned to the Archaeorthoptera nec Panorthoptera compose the outgroup. The ingroup is composed of three Panorthoptera nec Orthoptera and 63 Orthoptera, mainly from the Palaeozoic and Mesozoic. Following this initial phylogeny, we propose several nomenclatural changes; the Ensifera are redefined and the relationships between Caelifera and Ensifera sensu nov., and those between the major clades of modern Ensifera sensu nov., are clarified. Relationships within the ‘oedischioid’ stem-group remain unclear. The evolution of the venational structures within the Orthoptera is discussed and in this analysis the Orthoptera were not clearly affected by the Permo-Triassic biodiversity “crisis”. The capacity of the fossil taxa to be used in phylogenetic analyses is discussed, using the example of the ‘orthopteroid’ insects.

scholarly journals Redescription ofCalyptosuchus(Stagonolepis)wellesi(Archosauria: Pseudosuchia: Aetosauria) from the Late Triassic of the Southwestern United States with a discussion of genera in vertebrate paleontology

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4291 ◽  
Author(s):  
William G. Parker
Keyword(s):  
United States ◽  
Phylogenetic Analysis ◽  
Fossil Record ◽  
Phylogenetic Analyses ◽  
Western United States ◽  
Late Triassic ◽  
Vertebrate Paleontology ◽  
Unique Combination ◽  
Epistemological Problem ◽  
Chinle Formation

Calyptosuchus wellesiis a medium-sized desmatosuchian aetosaur common in Adamanian (early to middle Norian) age rocks from the Chinle Formation and Dockum Group of the Western United States. Known chiefly from osteoderms, this taxon has never been fully described and non-osteoderm material assigned toCalyptosuchushas been done so based on questionable criteria. Mapping of aetosaurian elements from thePlaceriasQuarry allows for the recognition of associated material providing support for referrals of non-osteoderm material. Furthermore, another previously undescribed specimen from the Chinle Formation of Arizona provides more details about this taxon. PresentlyCalyptosuchuslacks discrete autapomorphies, but can be distinguished from other aetosaurs based on a unique combination of characters supported by a phylogenetic analysis.Calyptosuchusis one of the most common aetosaurians in the Western United States and an index taxon of the early Adamanian biozone. The nameCalyptosuchusis retained and encouraged as the applicable genus name for the specieswellesirather than the often usedStagonolepisbecause assignments of taxa to multi-species genus names are problematic and in this case provides a proposed taxonomic relationship that cannot be unambiguously supported, even by phylogenetic analyses. Because of the inherent limitations of the fossil record, referral of specimens and species to species and genera respectively is an epistemological problem in vertebrate paleontology.

scholarly journals A new iguanodontian (Dinosauria: Ornithopoda) from the Early Cretaceous of Mongolia

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5300
Author(s):  
Terry A. Gates ◽  
Khishigjav Tsogtbaatar ◽  
Lindsay E. Zanno ◽  
Tsogtbaatar Chinzorig ◽  
Mahito Watabe
Keyword(s):  
Phylogenetic Analysis ◽  
Growth Stage ◽  
Phylogenetic Analyses ◽  
Type Specimen ◽  
Sister Taxon ◽  
New Taxon ◽  
Time Of Death ◽  
The North ◽  
Unusual Combination ◽  
Relationship Of

We describe a new iguanodontian ornithopod,Choyrodon barsboldigen. et sp. nov. from the Albian-aged Khuren Dukh Formation of Mongolia based on several partial skeletons interpreted to represent a subadult growth stage based on osteohistological features. This new taxon is diagnosed by many autapomorphies of the maxilla, nasal, lacrimal, opisthotic, predentary, and surangular.Choyrodondisplays an unusual combination of traits, possessing an open antorbital fenestra (a primitive ornithopod trait) together with derived features such as a downturned dentary and enlarged narial fenestra. Histological imaging suggests that the type specimen ofChoyrodonwould have been a subadult at the time of death. Phylogenetic analysis of two different character matrices do not positChoyrodonto be the sister taxon or to be more primitive than the iguanodontianAltirhinus kurzanovi, which is found in the same formation. The only resolved relationship of this new taxon is that it was hypothesized to be a sister-taxon with the North American speciesEolambia caroljonesa. Though discovered in the same formation andChoyrodonbeing smaller-bodied thanAltirhinus, it does not appear that the former species is an ontogimorph of the latter. Differences in morphology and results of the phylogenetic analyses support their distinction although more specimens of both species will allow better refinement of their uniqueness.

A new species of blind Trechinae from the Pyrenees of Huesca, and its position within Aphaenops (sensu stricto) (Coleoptera: Carabidae: Trechini)

Zootaxa ◽  
2010 ◽  
Vol 2566 (1) ◽  
pp. 49 ◽  
Author(s):  
ARNAUD FAILLE ◽  
CHARLES BOURDEAU ◽  
JAVIER FRESNEDA
Keyword(s):  
New Species ◽  
Molecular Data ◽  
Sensu Stricto ◽  
Sister Taxon ◽  
Mitochondrial Coi ◽  
First Time ◽  
A New Species

A new trechine species Aphaenops parvulus sp. n. (Carabidae, Trechini) is described from Esjamundo cave in the Pyrenees of Huesca, Spain. The new species belongs to the subgenus Aphaenops (sensu stricto), but differs from its closest congeners by the small size—it is the smallest species of the group—and characters of the aedeagus. Molecular data based on fragments of a mitochondrial (COI) and a nuclear (LSU) genes recognised Aphaenops parvulus sp. n. as a sister taxon to A. eskualduna Coiffait. Aphaenops eskualduna is reported from Spain with precision for the first time.

New aristonectine elasmosaurid plesiosaur specimens from the Early Maastrichtian of Angola and comments on paedomorphism in plesiosaurs

2015 ◽  
Vol 94 (1) ◽  
pp. 93-108 ◽  
Author(s):  
R. Araújo ◽  
M.J. Polcyn ◽  
J. Lindgren ◽  
L.L. Jacobs ◽  
A.S. Schulp ◽  
...  
Keyword(s):  
New Zealand ◽  
Histological Analysis ◽  
Phylogenetic Analyses ◽  
External Morphology ◽  
Sister Taxon ◽  
Close Relationship

AbstractNew elasmosaurid plesiosaur specimens are described from the Early Maastrichtian of Angola. Phylogenetic analyses reconstruct the Angolan taxon as an aristonectine elasmosaurid and the sister taxon of an unnamed form of similar age from New Zealand. Comparisons also indicate a close relationship with an unnamed form previously described from Patagonia. All of these specimens exhibit an ostensibly osteologically immature external morphology, but histological analysis of the Angolan material suggests an adult with paedomorphic traits. By extension, the similarity of the Angolan, New Zealand and Patagonian material indicates that these specimens represent a widespread paedomorphic yet unnamed taxon.

Selected Ordovician Trilobites from the Lake St. John District of Quebec and Their Bearing on Systematics

1995 ◽  
Vol 69 (S42) ◽  
pp. 1-19 ◽  
Author(s):  
Pierre J. Lespérance ◽  
Sylvain Desbiens
Keyword(s):  
Phylogenetic Analysis ◽  
Phylogenetic Analyses ◽  
Large Data ◽  
Minimal Length ◽  
Large Data Sets ◽  
Morphological Data ◽  
Eye Position ◽  
Data Sets ◽  
Close Relationship ◽  
The Status

The thorax of Hypodicranotus has ten segments and a spine on the eighth. The ages of Erratencrinurus s.l. spicatus and Erratencrinurus (Erratencrinurus?) vigilans in the Lake St. John district do not confirm their temporal roles leading to subgenera of Erratencrinurus, as has been recently suggested. Phylogenetic analyses of large data sets of species previously referred to Encrinuroides and Physemataspis yield a minimal length cladogram containing 18 species. Encrinuroides is restricted to four species, two of which have biogeographic affinities with Iapetus. These results lead to three clades, named the Walencrinuroides n. gen. clade, Frencrinuroides n. gen. clade, and finally the Physemataspis clade, with an enlarged concept of the genus with the erection of Physemataspis (Prophysemataspis) n. subgen. These last three clades are restricted to North America and Scotland, with alternating predominance of one region. Walencrinuroides s.l. gelaisi n. gen. n. sp. is described. New morphological data on Erratencrinurus s.l. spicatus confirm its close relationship with the clades discussed above. Data are insufficient for phylogenetic analysis of selected cheirurine species here surveyed. Eye position, glabellar segmentation, and pygidial shape differentiate the genera Ceraurus and Gabriceraurus; emended diagnoses of these genera are presented. Ceraurus globulobatus and C. matranseris are distinct, but morphologically close to one another. The status of Gabriceraurus dentatus can be stabilized on its extant types.

Description of a new specimen of Ianthasaurus hardestiorum (Eupelycosauria: Edaphosauridae) and a re-evaluation of edaphosaurid phylogeny

2010 ◽  
Vol 47 (6) ◽  
pp. 901-912 ◽  
Author(s):  
David M. Mazierski ◽  
Robert R. Reisz
Keyword(s):  
Phylogenetic Analysis ◽  
Fossil Record ◽  
Sister Taxon ◽  
Marginal Tooth ◽  
Tooth Morphology ◽  
Adult Individual ◽  
Full Resolution ◽  
Skeletal Material

Ianthasaurus hardestiorum , a basal edaphosaurid from the Upper Pennsylvanian of Garnett, Kansas, has been described on the basis of two incomplete, juvenile specimens and a series of disarticulated vertebral elements. New skeletal material of this poorly known species includes previously unknown cranial elements, increasing our knowledge of the anatomy and variation in this taxon. The complete ossification of the neural arches and the overall larger size of the vertebrae relative to those previously described indicate that they were part of an adult individual, and marginal tooth morphology resembles more closely that seen in the genus Edaphosaurus . Phylogenetic analysis of edaphosaurid synapsids confirms the hypothesis that Ianthasaurus is a sister-taxon of all other members of the clade. However, the incomplete fossil record of other putative edaphosaurids, such as Lupeosaurus and Glaucosaurus , makes full resolution of their phylogenetic interrelationships difficult to assess.

scholarly journals Identification of Hepatitis B virus putative intergenotype recombinants by using fragment typing

2006 ◽  
Vol 87 (8) ◽  
pp. 2203-2215 ◽  
Author(s):  
Jie Yang ◽  
Ke Xing ◽  
Riqiang Deng ◽  
Jinwen Wang ◽  
Xunzhang Wang
Keyword(s):  
Phylogenetic Analysis ◽  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Hot Spots ◽  
Phylogenetic Analyses ◽  
The Other ◽  
Consensus Sequences ◽  
B Virus ◽  
First Time ◽  
Recombination Breakpoints

Eight hundred and thirty-seven human Hepatitis B virus (HBV) genomes were categorized into pure genotypes and potential intergenotypes, according to their fragment types which were determined based on similarity and phylogenetic analyses of 13 contrived fragments of 250 bp against the corresponding fragments of the consensus sequences of genotypes A–H. Twenty-five intergenotypes, including 171 genomes, were revealed from the potential intergenotype recombinants by phylogenetic analysis of the precisely derived mosaic fragments. Among these, four new intergenotypes were discovered. Many genomes were revealed as putative intergenotype recombinants for the first time. About 87 % of the putative recombinants were B/C (120) and A/D (29) hybrids. The other recombinants comprised A/B/C, A/C, A/E, A/G, C/D, C/F, C/G, C/U (U for unknown genotype) and B/C/U hybrids. Genotypes A and C showed a higher recombination tendency than did other genotypes. The results also demonstrated region priority and breakpoint hot spots in the intergenotype recombination. Recombination breakpoints were found to be concentrated mainly in the vicinity of the DR1 region (nt 1640–1900), the pre S1/S2 region (nt 3150–100), the 3′-end of the C gene (nt 2330–2450) and the 3′-end of the S gene (nt 650–830). These results support the suggestion that intergenotype recombinants may result from co-infection with different genotypes.

scholarly journals Oldest cingulate skulls provide congruence between morphological and molecular scenarios of armadillo evolution

2011 ◽  
Vol 278 (1719) ◽  
pp. 2791-2797 ◽  
Author(s):  
Guillaume Billet ◽  
Lionel Hautier ◽  
Christian de Muizon ◽  
Xavier Valentin
Keyword(s):  
Phylogenetic Analysis ◽  
Fossil Record ◽  
Phylogenetic Analyses ◽  
Typical Case ◽  
New Taxon ◽  
Late Oligocene ◽  
Phylogenetic Studies ◽  
Molecular Phylogenetic ◽  
Early Neogene ◽  
Group A

The cingulates of the mammalian order Xenarthra present a typical case of disagreement between molecular and morphological phylogenetic studies. We report here the discovery of two new skulls from the Late Oligocene Salla Beds of Bolivia (approx. 26 Ma), which are the oldest known well-preserved cranial remains of the group. A new taxon is described: Kuntinaru boliviensis gen. et sp. nov. A phylogenetic analysis clusters K. boliviensis together with the armadillo subfamily Tolypeutinae. These skulls document an early spotty occurrence for the Tolypeutinae at 26 Ma, in agreement with the temporal predictions of previous molecular studies. The fossil record of tolypeutines is now characterized by a unique occurrence in the Late Oligocene, and a subsequent 12 Myr lack in the fossil record. It is noteworthy that the tolypeutines remain decidedly marginal in the Late Palaeogene and Early Neogene deposits, whereas other cingulate groups diversify. Also, the anatomical phylogenetic analysis herein, which includes K. boliviensis , is congruent with recent molecular phylogenetic analyses. Kuntinaru boliviensis is the oldest confident calibration point available for the whole Cingulata.

scholarly journals A revised global biogeography of turtles

2015 ◽  
Author(s):  
Walter G. Joyce ◽  
Márton Rabi
Keyword(s):  
Middle Jurassic ◽  
Fossil Record ◽  
Phylogenetic Analyses ◽  
Sensu Stricto ◽  
Early History ◽  
Marine Turtles ◽  
Biogeographic History ◽  
Global Presence ◽  
History Of ◽  
Phylogenetic Hypotheses

Background. Over the course of the last decades, much effort has gone into unraveling the biogeographic history of turtles, but while much progress has been achieved in resolving post- Jurassic dispersal events, traditional phylogenetic hypotheses have yielded incongruous results in regards to the early history of the group. Methods. We re-evaluate the fossil record of turtles in context of recent phylogenetic analyses and fossil finds, including the extensive record of fragmentary but diagnostic remains. Given that near-coastal and marine turtles readily disperse across aquatic barriers, a broad set of neritic to pelagic groups were disregarded from consideration. Significant disagreement still exists among current phylogenetic hypotheses and we therefore place much effort into tracing the fossil record of unambiguously monophyletic groups. We finally employed molecular backbone constraints, given that the molecular phylogenies are more consistent with the fossil record than current, morphological phylogenies. Results. Among derived, aquatic turtles, we recognize four clades that can be traced back to discrete biogeographic centers: Paracryptodira in North America and Europe, Pan- Cryptodira in Asia, Pan-Pelomedusoides in northern Gondwanan landmasses and Pan- Chelidae in southern Gondwanan landmasses. This pattern is partially mirrored by three clades of primarily terrestrial, basal turtles: Solemydidae in North American and Europe, Sichuanchelyidae in Asia, and Meiolaniformes sensu stricto in southern Gondwanan landmasses. Although the exact interrelationships of these clades remain unclear, most can be traced back to the Middle Jurassic. Discussion. The conclusion that the two primary lineages of pleurodires and paracryptodires can be traced back to mutually exclusive land masses is not novel, but the realization that the early history of pan-cryptodires is restricted to Asia has not been realized previously, because traditional phylogenies implied an early, global presence of pan-cryptodires. The timing of the origin of the three primary clades of derived turtles (i.e., Pan-Pleurodira, Pan-Cryptodira, and Paracryptodira) correlates with the opening of the central Atlantic and the formation of the Turgai Strait in the Middle Jurassic, somewhat later than predicted by molecular calibration studies. The primary diversity of extant turtles therefore appears to have been driven by vicariance. A similar hypothesis could also be formulated for the three clades of basal turtles that survive at least into the Late Cretaceous, but given that their combined monophyly remains uncertain, it is unclear if their diversity was also driven by vicariance, or if they emulate a vicariance-like pattern. Although most groups remained within their primary geographic range throughout their evolutionary history, the dominant vicariance signal was thoroughly obfuscated by rich dispersal from littoral to marine turtles and crown cryptodires.

Sign in / Sign up

Export Citation Format

Share Document