scholarly journals Neopterygian phylogeny: the merger assay

2018 ◽  
Vol 5 (3) ◽  
pp. 172337 ◽  
Author(s):  
Adriana López-Arbarello ◽  
Emilia Sferco
Keyword(s):  
Phylogenetic Relationships ◽  
Late Jurassic ◽  
Middle Triassic ◽  
Late Triassic ◽  
Future Research ◽  
Phylogenetic Hypothesis ◽  
Monophyletic Clade ◽  
Crown Group ◽  
Rapid Radiation ◽  
Cladistic Analyses

The phylogenetic relationships of the recently described genus † Ticinolepis from the Middle Triassic of the Monte San Giorgio are explored through cladistic analyses of the so far largest morphological dataset for fossil actinopterygians, including representatives of the crown-neopterygian clades Halecomorphi, Ginglymodi and Teleostei, and merging the characters from previously published systematic studies together with newly proposed characters. † Ticinolepis is retrieved as the most basal Ginglymodi and our results support the monophyly of Teleostei and Holostei, as well as Halecomorphi and Ginglymodi within the latter clade. The patterns of relationships within these clades mostly agree with those of previous studies, although a few important differences require future research. According to our results, ionoscopiforms are not monophyletic, caturids are not amiiforms and leptolepids and luisiellids form a monophyletic clade. Our phylogenetic hypothesis confirms the rapid radiation of the holostean clades Halecomorphi and Ginglymodi during the Early and Middle Triassic and the radiation of pholidophoriform teleosts during the Late Triassic. Crown-group Halecomorphi have an enormous ghost lineage throughout half of the Mesozoic, but ginglymodians and teleosts show a second radiation during the Early Jurassic. The crown-groups of Halecomorphi, Ginglymodi and Teleostei originated within parallel events of radiation during the Late Jurassic.

scholarly journals Mesozoic Coleopteran Faunas from Argentina: Geological Context, Diversity, Taphonomic Observations, and Comparison with Other Fossil Insect Records

2012 ◽  
Vol 2012 ◽  
pp. 1-14 ◽  
Author(s):  
María Belén Lara ◽  
Oscar Florencio Gallego ◽  
Lara Vaz Tassi
Keyword(s):  
Late Jurassic ◽  
Middle Triassic ◽  
Late Triassic ◽  
Animal Kingdom ◽  
Fossil Insect ◽  
San Luis ◽  
Fundamental Information ◽  
The World ◽  
Geological Units ◽  
Deseado Massif

The order Coleoptera is the most diversified group of the Class Insecta and is the largest group of the Animal Kingdom. This contribution reviews the Mesozoic insects and especially the coleopteran records from Argentina, based on bibliographical and unpublished materials (86 described species, 526 collected specimens). The material came from different geological units from the late Middle Triassic to the Late Triassic (Bermejo, Cuyo, and Malargüe basins) to the Middle-Late Jurassic and Early Cretaceous (Deseado Massif, Cañadón Asfalto, and San Luís Basin). The coleopteran record is composed of 29 described species with 262 collected specimens (isolated elytra) mainly represented by Triassic species and only four specimens recorded in Jurassic units, all of them currently unpublished. These fossil coleopterans provide fundamental information about the evolution of insects in the Southern Hemisphere and confirm the Triassic Argentinean insect deposits to be among the most important in the world.

scholarly journals Phylogenetic relationships among extinct and extant turtles: the position of Pleurodira and the effects of the fossils on rooting crown-group turtles

2010 ◽  
Vol 79 (3) ◽  
pp. 93-106 ◽  
Author(s):  
Juliana Sterli
Keyword(s):  
Phylogenetic Relationships ◽  
Sister Group ◽  
Molecular Data ◽  
Morphological Data ◽  
Phylogenetic Position ◽  
Separate Analysis ◽  
Crown Group ◽  
Rapid Radiation ◽  
Present Contribution ◽  
Origin And Evolution

The origin and evolution of the crown-group of turtles (Cryptodira + Pleurodira) is one of the most interesting topics in turtle evolution, second perhaps only to the phylogenetic position of turtles among amniotes. The present contribution focuses on the former problem, exploring the phylogenetic relationships of extant and extinct turtles based on the most comprehensive phylogenetic dataset of morphological and molecular data analyzed to date. Parsimony analyses were conducted for different partitions of data (molecular and morphological) and for the combined dataset. In the present analysis, separate analyses of the molecular data always retrieve Pleurodira allied to Trionychia. Separate analysis of the morphological dataset, by contrast, depicts a more traditional arrangement of taxa, with Pleurodira as the sister group of Cryptodira, being Chelonioidea the most basal cryptodiran clade. The simultaneous analysis of all available data retrieves all major extant clades as monophyletic, except for Cryptodira given that Pleurodira is retrieved as the sister group of Trionychia. The paraphyly of Cryptodira is an unorthodox result, and is mainly caused by the combination of two factors. First, the molecular signal allies Pleurodira and Trionychia. Second, the morphological data with extinct taxa locates the position of the root of crown-group Testudines in the branch leading to Chelonioidea. This study highlights major but poorly explored topics of turtle evolution: the alternate position of Pleurodira and the root of crown turtles. The diversification of crown turtles is characterized by the presence of long external branches and short internal branches (with low support for the internal nodes separating the major clades of crown turtles), suggesting a rapid radiation of this clade. This rapid radiation is also supported by the fossil record, because soon after the appearance of the oldest crown-group turtles (Middle-Late Jurassic of Asia) the number and diversity of turtles increases remarkably. This evolutionary scenario of a rapid diversification of modern turtles into the major modern lineages is likely the reason for the difficulty in determining the interrelationships and the position of the root of crown-group turtles.

Phylogenies and angiosperm diversification

Paleobiology ◽  
1993 ◽  
Vol 19 (2) ◽  
pp. 141-167 ◽  
Author(s):  
James A. Doyle ◽  
Michael J. Donoghue
Keyword(s):  
Early Cretaceous ◽  
Phylogenetic Trees ◽  
Sister Group ◽  
Late Triassic ◽  
Tectonic Activity ◽  
Crown Group ◽  
Extrinsic Factors ◽  
Angiosperm Diversification ◽  
Stem Lineage ◽  
Cladistic Analyses

Approaches to patterns of diversification based on counting taxa at a given rank can be misleading, even when all taxa are monophyletic. Such “rank-based” approaches are unable to reflect a hierarchy of evolutionary events because taxa of the same rank cannot be nested within one another. Phylogenetic trees specify an order of origination of characters and clades and can therefore be used in some cases to test hypotheses on causal relationships between characters and changes in diversity. “Tree-thinking” also clarifies discussions of the age of groups, by distinguishing between splitting of the stem-lineage from its sister group and splitting of the crown-group into extant clades.Cladistic evidence that Pentoxylon, Bennettitales, and Gnetales are the sister group of angiosperms implies that the angiosperm line (angiophytes) existed by the Late Triassic. The presence of primitive members of five basic angiosperm clades indicates that the crown-group (angiosperms) had begun to diversify by the mid-Early Cretaceous (Barremian-Aptian), but not necessarily much earlier. The greatest unresolved issue raised by cladistic analyses concerns the fact that the angiosperm tree can be rooted in two almost equally parsimonious positions. Trees rooted near Magnoliales (among “woody magnoliids”) suggest that the angiosperm radiation may have been triggered by the origin of intrinsic traits, e.g., a fast-growing, rhizomatous habit in the paleoherb and eudicot subgroup. However, trees rooted among paleoherbs, which are favored by rRNA data, imply that these traits are basic for angiosperms as a whole. This could mean that the crown-group originated not long before its radiation, or, if it did originate earlier, that its radiation was delayed due to extrinsic factors. Such factors could be a trend from environmental homogeneity and stability in the Jurassic to renewed tectonic activity and disturbance in the Early Cretaceous. Potentially relevant pre-Cretaceous fossils cannot be placed with confidence, but may be located along the stem-lineage (stem angiophytes); their generally paleoherb-like features favor the paleoherb rooting. The history of angiophytes may parallel that of Gnetales: some diversification of the stem-lineage in the Late Triassic, near disappearance in the Jurassic, and vigorous radiation of the crown-group in the Early Cretaceous.

scholarly journals A new stem turtle from the Middle Jurassic of Scotland: new insights into the evolution and palaeoecology of basal turtles

2008 ◽  
Vol 276 (1658) ◽  
pp. 879-886 ◽  
Author(s):  
Jérémy Anquetin ◽  
Paul M Barrett ◽  
Marc E.H Jones ◽  
Scott Moore-Fay ◽  
Susan E Evans
Keyword(s):  
Middle Jurassic ◽  
Late Jurassic ◽  
Evolutionary History ◽  
Sister Group ◽  
Late Triassic ◽  
Sister Group Relationship ◽  
New Taxon ◽  
Crown Group ◽  
History Of ◽  
Isle Of Skye

The discovery of a new stem turtle from the Middle Jurassic (Bathonian) deposits of the Isle of Skye, Scotland, sheds new light on the early evolutionary history of Testudinata. Eileanchelys waldmani gen. et sp. nov. is known from cranial and postcranial material of several individuals and represents the most complete Middle Jurassic turtle described to date, bridging the morphological gap between basal turtles from the Late Triassic–Early Jurassic and crown-group turtles that diversify during the Late Jurassic. A phylogenetic analysis places the new taxon within the stem group of Testudines (crown-group turtles) and suggests a sister-group relationship between E. waldmani and Heckerochelys romani from the Middle Jurassic of Russia. Moreover, E. waldmani also demonstrates that stem turtles were ecologically diverse, as it may represent the earliest known aquatic turtle.

Chronology of Tectonic Movement of Cratonic Basin: Insight from New Evidences from Ordos Basin, North China

2020 ◽  
Author(s):  
Dengfa He
Keyword(s):  
Early Cretaceous ◽  
Late Jurassic ◽  
Middle Triassic ◽  
Ordos Basin ◽  
Late Ordovician ◽  
Late Triassic ◽  
Tectonic Movement ◽  
The Ordos Basin ◽  
Middle Proterozoic ◽  
Cratonic Basin

<p>Craton is the stable unit of the lithosphere. The cratonic basin is thus the sedimentary basin developed upon craton. It has long been recognized as a kind of basin characterized by minor tectonic deformation and stable architecture. With the increasing evidences in the recent years, it is noticed that it has much more mobility, and is controlled not only by the lithospheric plate movements but also by the deep mantle activation. To explore the mobile behaviour of cratonic basin is an important window to address the intra-continental deformation mechanism. Taking the Ordos basin as an example, based on the new deep boreholes, the high-resolution seismic reflection profiles, cores, and the outcrops around the basin, the paper establishes the chronology of tectonic movement around the Ordos basin utilizing the integrated method of the isotopic dating, the bio-stratigraphy, and the sequence stratigraphy. It shows that, the basin developed the ten regional unconformities, underwent multi-period volcanic activities during the Middle Proterozoic, the late Early Paleozoic, the Late Triassic, and the Early Cretaceous. It was subjected to multi-stage compression, such as the Late Ordovician to Devonian, the Late Triassic, the Late Jurassic to Early Cretaceous, and the Neogene to Quaternary. Upon the crystalline basement of the Archaean and the Lower Proterozoic, the basin underwent five distinct extension-compression cycles, such as the extension in middle Proterozoic and compression in late Proterozoic, the extension in Cambrian to early Ordovician and compression in late Ordovician to Devonian, the extension in Carboniferous to middle Triassic and compression in late Triassic, the extension in early to middle Triassic and compression in late Jurassic to Cretaceous, and the extension in Paleogene and compression in Neogene to Quaternary, with a charter of a much longer period of the earlier cycle and a shorter period of the later cycle, and a longer period of extension and a shorter period of contraction in each cycle. The extension-compression cycle controlled the formation and evolution of the Ordos oil and gas super basin.</p>

scholarly journals Tip dating supports novel resolutions of controversial relationships among early mammals

2020 ◽  
Vol 287 (1928) ◽  
pp. 20200943
Author(s):  
Benedict King ◽  
Robin M. D. Beck
Keyword(s):  
Early Cretaceous ◽  
Late Jurassic ◽  
Morphological Evolution ◽  
Phylogenetic Analyses ◽  
Late Triassic ◽  
Crown Group ◽  
Jehol Biota ◽  
Rates Of Evolution ◽  
Mammal Evolution ◽  
Minimum Divergence

The estimation of the timing of major divergences in early mammal evolution is challenging owing to conflicting interpretations of key fossil taxa. One contentious group is Haramiyida, the earliest members of which are from the Late Triassic. Many phylogenetic analyses have placed haramiyidans in a clade with multituberculates within crown Mammalia, thus extending the minimum divergence date for the crown group deep into the Triassic. A second taxon of interest is the eutherian Juramaia from the Middle–Late Jurassic Yanliao Biota, which is morphologically very similar to eutherians from the Early Cretaceous Jehol Biota and implies a very early origin for therian mammals. Here, we apply Bayesian tip-dated phylogenetic methods to investigate these issues. Tip dating firmly rejects a monophyletic Allotheria (multituberculates and haramiyidans), which are split into three separate clades, a result not found in any previous analysis. Most notably, the Late Triassic Haramiyavia and Thomasia are separate from the Middle Jurassic euharamiyidans. We also test whether the Middle–Late Jurassic age of Juramaia is ‘expected’ given its known morphology by assigning an age prior without hard bounds. Strikingly, this analysis supports an Early Cretaceous age for Juramaia , but similar analyses on 12 other mammaliaforms from the Yanliao Biota return the correct, Jurassic age. Our results show that analyses incorporating stratigraphic data can produce results very different from other methods. Early mammal evolution may have involved multiple instances of convergent morphological evolution (e.g. in the dentition), and tip dating may be a method uniquely suitable to recognizing this owing to the incorporation of stratigraphic data. Our results also confirm that Juramaia is anomalous in exhibiting a much more derived morphology than expected given its age, which in turn implies very high rates of evolution at the base of therian mammals.

Progress and future directions in archosaur phylogenetics

2001 ◽  
Vol 75 (6) ◽  
pp. 1185-1201 ◽  
Author(s):  
Christopher A. Brochu
Keyword(s):  
Phylogenetic Relationships ◽  
Fossil Record ◽  
Middle Triassic ◽  
Basic Structure ◽  
Sources Of Information ◽  
Crown Group ◽  
Future Directions ◽  
Close Relationship ◽  
Divergence Timing

The basic structure of archosaurian phylogeny is understood to include two primary crown-group lineages—one leading to living crocodiles and including a broad diversity of Triassic animals (e.g., phytosaurs, rauisuchians, aetosaurs), and another leading to dinosaurs (living and extinct). These lineages were established by the middle Triassic. A few extinct groups remain controversial, such as the pterosaurs, and debate persists over the phylogenetic relationships among extant bird lineages, which have proved difficult to resolve, and divergence timing estimates within Aves and Crocodylia remain the source of contention. A few analyses support a close relationship between archosaurs and turtles, or even a nesting of turtles within Archosauria. All sources of information used to resolve these issues have weaknesses, and these problems all involve highly derived lineages when they first appear in the fossil record.

scholarly journals A new stem turtle from the Middle Jurassic of Scotland: new insights into the evolution and palaeoecology of basal turtles

2017 ◽  
Author(s):  
Jérémy Anquetin ◽  
Paul M. Barrett ◽  
Marc E. H. Jones ◽  
Scott Moore-Fay ◽  
Susan E. Evans
Keyword(s):  
Middle Jurassic ◽  
Late Jurassic ◽  
Evolutionary History ◽  
Sister Group ◽  
Late Triassic ◽  
Sister Group Relationship ◽  
New Taxon ◽  
Crown Group ◽  
History Of ◽  
Isle Of Skye

The discovery of a new stem turtle from the Middle Jurassic (Bathonian) deposits of the Isle of Skye, Scotland, sheds new light on the early evolutionary history of Testudinata. Eileanchelys waldmani gen. et sp. nov. is known from cranial and postcranial material of several individuals and represents the most complete Middle Jurassic turtle described to date, bridging the morphological gap between basal turtles from the Late Triassic–Early Jurassic and crown-group turtles that diversify during the Late Jurassic. A phylogenetic analysis places the new taxon within the stem group of Testudines (crown-group turtles) and suggests a sister-group relationship between E. waldmani and Heckerochelys romani from the Middle Jurassic of Russia. Moreover, E. waldmani also demonstrates that stem turtles were ecologically diverse, as it may represent the earliest known aquatic turtle.

A new species of spongiphorine earwig in Miocene amber from the Dominican Republic (Dermaptera: Spongiphoridae)

2019 ◽  
Vol 2 (6) ◽  
pp. 560-565
Author(s):  
MICHAEL S. ENGEL
Keyword(s):  
New Species ◽  
Fossil Record ◽  
Late Jurassic ◽  
Late Triassic ◽  
Crown Group ◽  
Rich Variety ◽  
Extant Species ◽  
The World ◽  
Early Neogene ◽  
A New Species

Earwigs (Dermaptera) are an often-ignored group of polyneopteran insects, with nearly 2000 extant species distributed throughout the world (Grimaldi & Engel, 2005; Stork, 2018). All of the modern diversity belongs to the suborder Neodermaptera, a clade that first definitively appears in the Early Cretaceous (Engel et al., 2011; Wolfe et al., 2016), but likely diverged in the Late Jurassic, although there is a rich gradation of earlier earwig variety extending back to at least the Late Triassic (Kelly et al., 2017). The earlier-diverging lineages (such as Archidermaptera, Eodermaptera, and Turanodermaptera [Turanodermatidae]) lack some of the otherwise characteristic synapomorphies of crown-group Dermaptera, such as loss of ocelli, loss of tegminal venation, or reduction of the ovipositor (Grimaldi & Engel, 2005). While there is a rich variety of forms and morphological disparity among fossil Dermaptera, their record compared to other orders remains comparatively meagre. Given this overall scarcity in the fossil record, there is nonetheless a decent variety of lineages documented from various Cenozoic deposits (Wappler et al., 2005). A fairly large number of taxa have been described from Palaeogene and early Neogene impressions (e.g., Heer, 1865; Zhang, 1989; Zhang et al., 1994; Chatzimanolis & Engel, 2010), although the precise systematic placement of many are challenging to confirm given the nature of their preservation and the characters widely needed to properly assign earwigs. Those species preserved as amber inclusions offer a wider breadth of characters from which to ascertain affinities, and earwigs have been previously described from Oise, Baltic, Dominican, and Mexican ambers (Burr, 1911a; Nel et al., 2003; Ross & Engel, 2013; Engel, 2016, 2017).

scholarly journals Remarkable teleostean fishes from the Late Jurassic of southern Germany and their phylogenetic relationships

Fossil Record ◽  
2000 ◽  
Vol 3 (1) ◽  
pp. 137-179 ◽  
Author(s):  
G. Arratia
Keyword(s):  
New Taxa ◽  
Phylogenetic Relationships ◽  
Late Jurassic ◽  
Sister Group ◽  
Morphological Characters ◽  
Phylogenetic Position ◽  
New Genera ◽  
Phylogenetic Hypothesis ◽  
The Past ◽  
New Information

Complete descriptions, as preservation permits, are provided for new Late Jurassic taxa (e.g., †<i>Ascalabothrissops voelkli</i> n. gen. and n. sp., †<i>Anaethalion zapporum</i> n. sp., and †<i>Elopsomolos frickhingeri</i> n. gen. and n. sp.); the phylogenetic positions of these taxa are given, as well as an evaluation of the European teleosts during the Late Jurassic. <br><br> The relationships among certain fossil and extant teleosts are evaluated based on 191 unweighted morphological characters by using cladistic principles. The results suggest that †<i>Ascalabothrissops</i> n. gen. from the Kimmeridgian of Schamhaupten is the sister-taxon of †<i>Pachythrissops</i> from the Tithonian of Bavaria, and consequently is an ichthyodectiform. †<i>Anaethalion zapporum</i> n. sp., an elopiform, stands in an unresolved polytomy with †<i>A. angustus, †A. knorri</i>, and a clade formed by †<i>A. angustissimus</i> and more advanced elopiforms. The new results confirm Arratia (1997) that †<i>Anaethalion</i>, as presently understood, is a paraphyletic taxon. †<i>Elopsomolos frickhingeri</i> n. gen. and n. sp. forms a polytomy with †<i>Elopsomolos</i> sp. 1 and 3, and [<i>Elops + Megalops</i>]. Monophyly of the Kimmeridgian and Tithonian genus †<i>Elopsomolos</i> is not certain. <br><br> Following the new phylogenetic hypothesis, that includes new taxa and new characters, the elopomorphs stand as the primitive sister-group of osteoglossomorphs and more advanced teleosts. The new information does not affect the phylogenetic position of the main extant teleostean clades and confirms previous results by Arratia (1991, 1996, 1997, 1999). <br><br> The analysis of the elopiforms through time shows that the group had an important radiation during the Late Jurassic, to be replaced by new genera and species during the Cretaceous, and again during the Cenozoic. From numerous genera living in the past, elopiforms are represented now by two genera, <i>Elops</i> and <i>Megalops</i>. <br><br> Soweit es die Erhaltung zulässt, werden vollständige Beschreibungen der drei neuen spätjurassischen Taxa †<i>Ascalabothrissops voelkli</i> n. gen. et n. sp., †<i>Anaethalion zapporum</i> n. sp., und †<i>Elopsomolos frickhingeri</i> n. gen. et n. sp. gegeben. Die phylogenetische Stellung dieser Taxa als auch anderer spätjurassischer europäischer Teleosteer ist analysiert. <br><br> Die Verwandtschaftsbeziehungen innerhalb einiger fossiler und rezenter Teleosteer wurden auf der Basis von 191 nicht gewichteten morphologischen Merkmalen mit Hilfe der kladistischen Methode evaluiert. Als Ergebnis zeigt sich, dass †<i>Ascalabothrissops</i> n. gen. aus dem Kimmeridgium von Schamhaupten das Schwestertaxon von †<i>Pachythrissops</i> und damit ein Ichthyodectiformer ist. †<i>Anaethalion zapporum</i> n. sp., ein Elopiformer, steht in einer nicht auflösbaren Polytomie mit †<i>A. angustus, †A, knorri</i>, und einer Gruppe gebildet aus †<i>A. angustissimus</i> und weiter fortgeschrittenen Elopiformen. Die neuen Ergebnisse bestätigen Arratia (1997), dass †<i>Anaethalion</i>, wie zur Zeit umgrenzt, ein paraphylethisches Taxon darstellt. †<i>Elopsomolos frickhingeri</i> n. gen. et n. sp. bildet eine Polytomie mit †<i>Elopsomolos</i> sp. 1 und 3, und [<i>Elops + Megalops</i>]. Die Monophylie der Gattung †<i>Elopsomolos</i> aus dem Kimmeridgium und Tithonium ist nicht gesichert. <br><br> Nach der neuen phylogenetischen Hypothese, die neue Taxa und neue Merkmale einbezieht, sind die Elopomorphen die primitive Schwestergruppe der Osteoglossomorphen und weiter fortgeschrittener Teleosteer. Die neuen Ergebnisse beeinflussen die phylogenetische Stellung der rezenten Hauptgruppen der Teleosteer nicht und bestätigen frühere Ergebnisse von Arratia (1991, 1996, 1997, 1999). <br><br> Die Analyse der Elopiformen zeigt, dass die Gruppe eine bedeutende Radiation im Spätjura erlebte; neue Gattungen und Arten traten in der Kreide auf und dann wieder im Känozoikum. Im Gegensatz zu den zahlreichen fossilen Gattungen sind die Elopiformen heute nur durch zwei Gattungen vertreten, <i>Elops</i> und <i>Megalops</i>. <br><br> doi:<a href="http://dx.doi.org/10.1002/mmng.20000030108" target="_blank">10.1002/mmng.20000030108</a>

Sign in / Sign up

Export Citation Format

Share Document