Permian Hyolithida from Australia: the last of the hyoliths?

2009 ◽  
Vol 83 (1) ◽  
pp. 147-152 ◽  
Author(s):  
John M. Malinky
Keyword(s):  
Population Size ◽  
Upper Permian ◽  
Late Paleozoic ◽  
Early Cambrian ◽  
Progressive Decline ◽  
Early Devonian ◽  
Extinction Event ◽  
Permian Extinction ◽  
Abundance And Diversity ◽  
Geologic Record

Class Hyolitha Marek, 1963 encompassing the Order Hyolithida Sysoev, 1957 (Early Cambrian to Upper Permian) and Order Orthothecida Marek, 1966 (Early Cambrian to Early Devonian) consists of a group of conical, calcareous-shelled invertebrates of controversial affinity. One opponent view holds that hyoliths may be reasonably accommodated under the Phylum Mollusca (Malinky and Yochelson, 2007 and references therein), whereas another supports separate phylum status under the name Hyolitha (Pojeta, 1987 and references therein). Hyolith abundance and diversity attain a maximum in the Cambrian, followed by a progressive decline up to their Permian extinction (Fisher, 1962; Wills, 1993). Their demise was part of the extinction event of the Late PermianlEarly Triassic. The cause(s) of this event remains controversial (Erwin et al., 2002), and no imprint remains in the geologic record of the specific circumstances surrounding the disappearance of the hyoliths, though it is highly probable that reduced population size was a contributing factor. Given the overall rarity of Late Paleozoic hyoliths, every occurrence is worthy of note to better understand patterns of hyolith diversity and abundance in the Late Paleozoic, the geographic and stratigraphic distribution of hyolith taxa and circumstances related to their extinction. The species from the Upper Permian described herein is among the youngest, if not the youngest, members of class Hyolitha.

The rise and fall of late Paleozoic trilobites of the United States

1999 ◽  
Vol 73 (2) ◽  
pp. 164-175 ◽  
Author(s):  
David K. Brezinski
Keyword(s):  
United States ◽  
North America ◽  
Sea Level ◽  
Adaptive Radiation ◽  
The United States ◽  
Upper Permian ◽  
Late Paleozoic ◽  
Lower Permian ◽  
Stage 4 ◽  
Stage 1

Based on range data and generic composition, four stages of evolution are recognized for late Paleozoic trilobites of the contiguous United States. Stage 1 occurs in the Lower Mississippian (Kinderhookian-Osagean) and is characterized by a generically diverse association of short-ranging, stenotopic species that are strongly provincial. Stage 2 species are present in the Upper Mississippian and consist of a single, eurytopic, pandemic genus, Paladin. Species of Stage 2 are much longer-ranging than those of Stage 1, and some species may have persisted for as long as 12 m.y. Stage 3 is present within Pennsylvanian and Lower Permian strata and consists initially of the eurytopic, endemic genera Sevillia and Ameura as well as the pandemic genus Ditomopyge. During the middle Pennsylvanian the very long-ranging species Ameura missouriensis and Ditomopyge scitula survived for more than 20 m.y. During the late Pennsylvanian and early Permian, a number of pandemic genera appear to have immigrated into what is now North America. Stage 4 is restricted to the Upper Permian (late Leonardian-Guadalupian) strata and is characterized by short-ranging, stenotopic, provincial genera.The main causal factor controlling the four-stage evolution of late Paleozoic trilobites of the United States is interpreted to be eustacy. Whereas Stage 1 represents an adaptive radiation developed during the Lower Mississippian inundation of North America by the Kaskaskia Sequence, Stage 2 is present in strata deposited during the regression of the Kaskaskia sea. Stage 3 was formed during the transgression and stillstand of the Absaroka Sequence and, although initially endemic, Stage 3 faunas are strongly pandemic in the end when oceanic circulation patterns were at a maximum. A mid-Leonardian sea-level drop caused the extinction of Stage 3 fauna. Sea-level rise near the end of the Leonardian and into the Guadalupian created an adaptive radiation of stentopic species of Stage 4 that quickly became extinct with the latest Permian regression.

The amalgamation of Pangea: Paleomagnetic and geological observations revisited

2020 ◽  
Author(s):  
Lei Wu ◽  
J. Brendan Murphy ◽  
Cecilio Quesada ◽  
Zheng-Xiang Li ◽  
John W.F. Waldron ◽  
...  
Keyword(s):  
Selection Criteria ◽  
Late Paleozoic ◽  
Geological Data ◽  
High Quality ◽  
Early Devonian ◽  
Polar Wander ◽  
Middle Ordovician ◽  
Oblique Convergence ◽  
Q Factors ◽  
European Variscides

The supercontinent Pangea formed by the subduction of the Iapetus and Rheic oceans between Gondwana, Laurentia, and Baltica during mid-to-late Paleozoic times. However, there remains much debate regarding how this amalgamation was achieved. Most paleogeographic models based on paleomagnetic data argue that the juxtaposition of Gondwana and Laurussia (Laurentia-Baltica) was achieved via long-lasting highly oblique convergence in the late Paleozoic. In contrast, many geology-based reconstructions suggest that the collision between the two continents was likely initiated via a Gondwanan promontory comprising the Iberian, Armorican, and Bohemian massifs, and parts of the basement units in the Alpine orogen during the Early Devonian. To help resolve this discrepancy, we present an updated compilation of high-quality paleopoles of mid-to-late Paleozoic ages (spanning Middle Ordovician and Carboniferous times) from Gondwana, Laurentia, and Baltica. These paleopoles were evaluated with the Van der Voo selection criteria, corrected for inclination error where necessary, and were used to revise their apparent polar wander (APW) paths. The revised APW paths were constructed using an innovative approach in which age errors, A95 ovals, and Q-factors of individual paleopoles are taken into account. By combining the resulting APW paths with existing geological data and field relationships in the European Variscides, we provide mid-to-late Paleozoic paleogeographic reconstructions which indicate that the formation of Pangea was likely initiated at 400 Ma via the collision between Laurussia and a ribbon-like Gondwanan promontory that was itself formed by a scissor-like opening of the Paleotethys Ocean, and that the amalgamation culminated in the mostly orthogonal convergence between Gondwana and Laurussia.

Theoretical Ecospace for Ecosystem Paleobiology: Energy, Nutrients, Biominerals, and Macroevolution

2013 ◽  
Vol 19 ◽  
pp. 1-20 ◽  
Author(s):  
Andrew M. Bush ◽  
Sara B. Pruss
Keyword(s):  
Ecosystem Dynamics ◽  
Early Cambrian ◽  
Nutrient Cycles ◽  
Earth System ◽  
Ecological Traits ◽  
Ecological Processes ◽  
History Of ◽  
Extinction Selectivity ◽  
Abundance And Diversity ◽  
Selective Extinction

Changes in nutrient cycles and energy fluxes (i.e., ecosystem dynamics) likely drove numerous trends and disruptions in the history of life. Advances in geochemistry offer great insights into paleoecosystem function, as does an understanding of the biogeochemical roles played by ancient organisms. A theoretical ecospace that describes the chemical exchanges between organisms and their environments is presented. Previous descriptions of ecospace principally described spatial and physical aspects of ecology; the new ecospace description broadens the concept to encompass a wider range of ecological processes that control abundance and diversity of fossil organisms. Organisms require materials from the environment for generating energy and building tissues, and these factors are broken down, ultimately specifying particular substances acquired from the environment. Different organisms require specific substances in different amounts depending on factors such as physiology, environmental conditions, etc.; thus, physiological ecospace describes an organism's sensitivity to ecosystem/earth system perturbations and trends. Several examples relating to organisms' requirements for skeletal minerals are reviewed, and a new analysis of extinction selectivity related to ocean acidification is presented. Selective extinction of heavily calcified metazoa is demonstrated to have occurred at least eight times during the Phanerozoic, including the early Cambrian, Frasnian (Late Devonian), and Aptian (Early Cretaceous). Multidimensional structure of ecospace occupation (e.g., correlations among ecological traits) strongly controls the effects of an extinction such that the same kill mechanism applied at different times will affect the ecological composition of the biosphere in a variety of ways.

Inozoan calcareous Porifera from the Permian reefs in South China

1989 ◽  
Vol 63 (6) ◽  
pp. 778-800 ◽  
Author(s):  
J. Keith Rigby ◽  
Fan Jiasong ◽  
Zhang Wei
Keyword(s):  
South China ◽  
Growth Form ◽  
Carbonate Platform ◽  
Upper Permian ◽  
General Nature ◽  
Late Paleozoic ◽  
Changxing Formation ◽  
Middle And Upper Permian ◽  
Eastern Sichuan

Inozoans are described from patch reefs on the carbonate platform of eastern Sichuan, from the uppermost Permian Laolongdong reefs in the Changxing Formation (Kazanian–Tatarian) at Beipei, northwest of Chongqing, and from Middle and Upper Permian reefs from the Maokou (Kungurian), Wujiaping (Ufimian), and Changxing Formations at Xiangbo, Longlin County, in northwestern Guangxi. Classification of inozoans, particularly late Paleozoic ones, is still in a state of flux, but genera recognized to date can be keyed using the general nature of the spongocoel, canals, and growth form.New genera described are Intratubospongia, Grossotubenella, Cavusonella, and Radicanalospongia. The new species described are Stellispongia radiata, S. minor, Peronidella beipeiensis, P. regulara, P. parva, Intratubospongia typica, I. tenuiperforata, I. multisi-phonata, I. minima, Grossotubenella parallela, Cavusonella caverna, and Radicanalospongia normala. A Corynella that is not identifiable to species and a sphinctozoan-like inozoan(?) sp. A that has a fibrous-appearing internal skeleton but is poorly preserved are also described. Inozoans and other sponges are major frame-builders in the Permian reefs of South China and our fauna is one of the most diverse late Paleozoic assemblages described to date.

End-Permian mass extinction of foraminifers in the Nanpanjiang basin, South China

2009 ◽  
Vol 83 (5) ◽  
pp. 718-738 ◽  
Author(s):  
Haijun Song ◽  
Jinnan Tong ◽  
Z. Q. Chen ◽  
Hao Yang ◽  
Yongbiao Wang
Keyword(s):  
New Species ◽  
Quantitative Analysis ◽  
South China ◽  
Contact Surface ◽  
Mass Extinction ◽  
Extinction Rates ◽  
Extinction Event ◽  
Permian Extinction ◽  
Permian Mass Extinction ◽  
A New Species

Newly obtained foraminifer faunas from the Permian-Triassic (P-Tr) transition at the Dajiang and Bianyang sections in the Nanpanjiang Basin, South China, comprise 61 species in 40 genera. They belong to thePalaeofusulina sinensisZone, the youngest Permian foraminifer zone in South China. Quantitative analysis reveals that the last occurrences of more than a half of species (28/54) fall into a 60-cm-interval at the uppermost Changhsingian skeletal packstone unit and thus calibrate the end-Permian extinction to the skeletal packstonecalcimicrobial framestone boundary. About 93% (54/58) of species of the latest Permian assemblage became extinct in the P-Tr crisis. Four major foraminiferal groups, the Miliolida, Fusulinida, Lagenida, and Textulariina, have extinction rates up to 100%, 96%, 92%, and 50%, respectively, and thus experienced selective extinctions. BothHemigordius longusand ?Globivalvulina bulloidestemporarily survived the end-Permian extinction event and extended into the earliest Triassic but became extinct soon after. The post-extinction foraminifer assemblage is characterized by the presence of both disaster taxa and Lazarus taxa. Foraminifer distribution near the P-Tr boundary also reveals that the irregular contact surface at the uppermost Permian may be created by a massive submarine dissolution event, which may be coeval with the end-Permian mass extinction. A new species,Rectostipulina hexamerata,is described here.

scholarly journals Echinoids from the Tesero Member (Werfen Formation) of the Dolomites (Italy): implications for extinction and survival of echinoids in the aftermath of the end-Permian mass extinction

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e7361
Author(s):  
Jeffrey R. Thompson ◽  
Renato Posenato ◽  
David J. Bottjer ◽  
Elizabeth Petsios
Keyword(s):  
Mass Extinction ◽  
Sea Urchins ◽  
Northern Italy ◽  
Early Triassic ◽  
Crown Group ◽  
Stem Group ◽  
Extinction Event ◽  
Permian Extinction ◽  
Permian Mass Extinction ◽  
A New Species

The end-Permian mass extinction (∼252 Ma) was responsible for high rates of extinction and evolutionary bottlenecks in a number of animal groups. Echinoids, or sea urchins, were no exception, and the Permian to Triassic represents one of the most significant intervals of time in their macroevolutionary history. The extinction event was responsible for significant turnover, with the Permian–Triassic representing the transition from stem group echinoid-dominated faunas in the Palaeozoic to Mesozoic faunas dominated by crown group echinoids. This turnover is well-known, however, the environmental and taxonomic distribution of echinoids during the latest Permian and Early Triassic is not. Here we report on an echinoid fauna from the Tesero Member, Werfen Formation (latest Permian to Early Triassic) of the Dolomites (northern Italy). The fauna is largely known from disarticulated ossicles, but consists of both stem group taxa, and a new species of crown group echinoid,Eotiaris teseroensisn. sp. That these stem group echinoids were present in the Tesero Member indicates that stem group echinoids did not go extinct in the Dolomites coincident with the onset of extinction, further supporting other recent work indicating that stem group echinoids survived the end-Permian extinction. Furthermore, the presence ofEotiarisacross a number of differing palaeoenvironments in the Early Triassic may have had implications for the survival of cidaroid echinoids during the extinction event.

The Search for an Extinction Event

1994 ◽  
Vol 7 ◽  
pp. 467-486
Author(s):  
Rodney M. Feldmann
Keyword(s):  
Population Size ◽  
Time Interval ◽  
Personal Event ◽  
Extinction Event ◽  
Species Declines

Death of an organism is a very personal event. The extinction of a species is viewed as catastrophic, only if one is a member of that species. In fact, the extinction of a species simply represents the sum total of deaths of individuals within the species during a time interval in which the rate of death exceeds the rate of recruitment of new individuals. That is, the population size within the species declines to the point that the unit is no longer reproductively viable.

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