A new stemmed echinoderm from the Furongian of China and the origin of Glyptocystitida (Blastozoa, Echinodermata)

2016 ◽  
Vol 154 (3) ◽  
pp. 465-475 ◽  
Author(s):  
SAMUEL ZAMORA ◽  
COLIN D. SUMRALL ◽  
XUE-JIAN ZHU ◽  
BERTRAND LEFEBVRE
Keyword(s):  
Phylogenetic Analysis ◽  
South China ◽  
Sister Group ◽  
Character Evolution ◽  
Clear Understanding ◽  
Late Cambrian ◽  
History Of

AbstractThe Furongian (late Cambrian) is an extremely poorly sampled time in the history of echinoderms, with only few localities yielding complete specimens. Here, we document an exquisitely preserved stemmed echinoderm from the Furongian Sandu Formation in South China that provides important new data illuminating the origin of Glyptocystitida, a common Palaeozoic clade of echinoderms. Sanducystis sinensis n. gen. n. sp. displays an organized theca bearing three circlets of plates (basal, infralateral and lateral), a laterally positioned periproct in the CD interray, a lack of respiratory pectinirhombs and a stem divided in two parts, with expanded inner and outer columnals proximally and narrow, elongate, homeomorphic columnals distally. A phylogenetic analysis places Sanducystis more derived than the columnal-bearing ‘eocrinoid’ Ridersia and sister group of a clade encompassing Macrocystella-like glyptocystitoid rhombiferans from the Furongian onwards. By filling in an important morphological gap, Sanducystis provides a clear understanding of character evolution within Glyptocystitida.

scholarly journals Rhadinopyga n. gen. from the “Vogelkop” of New Guinea and Adjacent Islands, a New Genus of the Subtribe Cosmopsalrtiaria (Homoptera, Cicadoidea: Cicadidae)

1985 ◽  
Vol 55 (2) ◽  
pp. 275-279 ◽  
Author(s):  
J.P. Duffels
Keyword(s):  
Phylogenetic Analysis ◽  
New Genus ◽  
New Guinea ◽  
Sister Group ◽  
Historical Biogeography ◽  
Sister Group Relationship ◽  
Geological History ◽  
History Of ◽  
Relationship Of

Rhadinopyga n. gen. is erected for Diceropyga recedens (Walker) from Salawati, D. impar (Walker) and D. acuminata Duffels, both from Waigeo, and Rhadinopyga epiplatys n. sp. from the “Vogelkop” area ( = Tjendrawasih) of New Guinea and the islands of Misoöl and Batjan. Phylogenetic analysis suggests a sister-group relationship of Rhadinopyga n. gen. and Diceropyga Stål. The endemism of Rhadinopyga in the “Vogelkop” area is discussed in connection with the geological history of the area and the historical biogeography of the subtribe Cosmopsaltriaria.

scholarly journals New taxa and phyletic evolution of the Aeronian (Llandovery, Silurian) Petalocrinidae (Echinodermata, Crinoidea) in Guizhou, South China Block

2017 ◽  
Vol 91 (3) ◽  
pp. 477-492 ◽  
Author(s):  
Yingyan Mao ◽  
William I. Ausich ◽  
Yue Li ◽  
Jih-Pai Lin ◽  
Caihua Lin
Keyword(s):  
Phylogenetic Analysis ◽  
New Species ◽  
New Taxa ◽  
South China ◽  
Sister Group ◽  
South China Block ◽  
The South ◽  
Evolutionary Patterns ◽  
Systematic Paleontology ◽  
Three New Species

AbstractSystematic paleontology of three new species of Petalocrinidae (Crinoidea) are documented from the carbonate-dominated units of the Shihniulan and equivalent Leijiatun formations (Llandovery, Silurian) of the Baisha, Fengxiang, and Shuibatang sections in Guizhou (China). New taxa are from the Upper Yangtze Epicontinental Sea of the South China Block. The new taxa include Petalocrinus stenopetalus new species, Spirocrinus circularis new species, and S. dextrosus new species. They have a narrow spatial and temporal (Aeronian) distribution. Evolutionary patterns of the four genera of Petalocrinidae are outlined based on the specialized characters of the fused arm plates. Phylogenetic analysis was used to assess morphological relationships within the Petalocrinidae. Petalocrinus inferior represents the plesiomorphic condition for the group and nests as a sister group of P. stenopetalus n. sp. and the Spirocrinus species used in this analysis and the clade exclusively comprised of Sinopetalocrinus. The phylogenetic analysis suggests that Petalocrinus, as currently defined, might be a paraphyletic genus.

scholarly journals A new balaenopterid whale from the late Miocene of the Southern North Sea Basin and the evolution of balaenopterid diversity (Cetacea, Mysticeti)

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e6915 ◽  
Author(s):  
Michelangelo Bisconti ◽  
Dirk K. Munsterman ◽  
Klaas Post
Keyword(s):  
Phylogenetic Analysis ◽  
North Sea ◽  
Sister Group ◽  
Morphological Characters ◽  
Monophyletic Group ◽  
New Taxon ◽  
Skull Morphology ◽  
The North ◽  
History Of ◽  
Morphological Transformations

Background Balaenopterid mysticetes represent the most successful family-rank group of this clade. Their evolutionary history is characterized by a rich fossil record but the origin of the living genera is still largely not understood. Recent discoveries in the southern border of the North Sea revealed a number of well preserved fossil balaenopterid whales that may help resolving this problem. In particular, skull NMR 14035 shares morphological characters with the living humpback whale, Megaptera novaeangliae and, for this reason, its characteristics are investigated here. Methods The comparative anatomical analysis of the new specimen formed the basis of a new phylogenetic analysis of the Mysticeti based on a matrix including 350 morphological character states scored for 82 Operational Taxonomic Units. The stratigraphic age of the specimen was determined based on the analysis of the dinocyst assemblage recovered in the associated sediment. We assessed clade diversity in Balaenopteridae by counting the numbers of clades in given time intervals and then plotted the results. Results Nehalaennia devossi n. gen. et sp. is described for the first time from the late Tortonian (8.7–8.1 Ma) of the Westerschelde (The Netherlands). This new taxon belongs to Balaenopteridae and shows a surprisingly high number of advanced characters in the skull morphology. Nehalaennia devossi is compared to a large sample of balaenopterid mysticetes and a phylogenetic analysis placed it as the sister group of a clade including the genus Archaebalaenoptera. The inclusion of this fossil allowed to propose a phylogenetic hypothesis for Balaenopteridae in which (1) Eschrichtiidae (gray whales) represents a family of its own, (2) Balaenopteridae + Eschrichtiidae form a monophyletic group (superfamily Balaenopteroidea), (3) Cetotheriidae is the sister group of Balaenopteroidea, (4) living Balaenoptera species form a monophyletic group and (5) living M. novaeangliae is the sister group of Balaenoptera. Our work reveals a complex phylogenetic history of Balaenopteridae and N. devossi informs us about the early morphological transformations in this family. Over time, this family experienced a number of diversity pulses suggesting that true evolutionary radiations had taken place. The paleoecological drivers of these pulses are then investigated.

Phylogenetic Analysis of T-Box Genes Demonstrates the Importance of Amphioxus for Understanding Evolution of the Vertebrate Genome

Genetics ◽  
2000 ◽  
Vol 156 (3) ◽  
pp. 1249-1257
Author(s):  
Ilya Ruvinsky ◽  
Lee M Silver ◽  
Jeremy J Gibson-Brown
Keyword(s):  
Phylogenetic Analysis ◽  
Whole Genome Duplication ◽  
Genome Duplication ◽  
Gene Families ◽  
Vertebrate Evolution ◽  
Whole Genome ◽  
Vertebrate Genome ◽  
T Box ◽  
Genetic Complexity ◽  
History Of

Abstract The duplication of preexisting genes has played a major role in evolution. To understand the evolution of genetic complexity it is important to reconstruct the phylogenetic history of the genome. A widely held view suggests that the vertebrate genome evolved via two successive rounds of whole-genome duplication. To test this model we have isolated seven new T-box genes from the primitive chordate amphioxus. We find that each amphioxus gene generally corresponds to two or three vertebrate counterparts. A phylogenetic analysis of these genes supports the idea that a single whole-genome duplication took place early in vertebrate evolution, but cannot exclude the possibility that a second duplication later took place. The origin of additional paralogs evident in this and other gene families could be the result of subsequent, smaller-scale chromosomal duplications. Our findings highlight the importance of amphioxus as a key organism for understanding evolution of the vertebrate genome.

scholarly journals Geldtheorie und -politik in Preußen Mitte des 18. Jahrhunderts

2020 ◽  
Vol 61 (1) ◽  
pp. 217-257
Author(s):  
Jan Greitens
Keyword(s):  
18Th Century ◽  
Economic Thought ◽  
Monetary Theory ◽  
Clear Understanding ◽  
Monetary System ◽  
Monetary Approach ◽  
History Of ◽  
Early Modern Era ◽  
Value Of Money ◽  
Modern Era

AbstractIn the history of economic thought, monetary theories in the Germanspeaking world of the early modern era are considered backward compared to the approaches in other European countries. This backwardness can be illustrated by two authors from the mid-18th century who were not only contemporaries but also successively in the service of Frederick II (“the Great”) of Prussia. The first is Johann Philipp Graumann, one of the 'projectors' of the 18th century. As master of the mints in Prussia, he developed a coin project, where he tried to implement a new monetary standard to promote trade, generate seigniorage income and implement the Prussian coins as a kind of a reserve currency. In his writings, he developed a typical mercantilistic monetary theory with a clear understanding of the mechanism in the balance of payments. But even when he tried to include credit instruments, he did not take banks or broader financial markets into account. The second thinker is Johann Heinrich Gottlob Justi, who took the opposite position concerning the coin project as well as in his theory. He defended a strictly metalistic monetary approach where the value of money is only based on the metal's value. While Graumann rejected the English coin system, Justi recommended its laws for countries without their own mines, because the sovereign should not misuse his right of coinage. For him, the monetary system had tobe reliable and stable to serve trade and economic development.

Basal Cambrian microfossils from the Yangtze Gorges area (South China) and the Aksu area (Tarim block, northwestern China)

2009 ◽  
Vol 83 (1) ◽  
pp. 30-44 ◽  
Author(s):  
Lin Dong ◽  
Shuhai Xiao ◽  
Bing Shen ◽  
Chuanming Zhou ◽  
Guoxiang Li ◽  
...  
Keyword(s):  
Geographic Distribution ◽  
South China ◽  
Northwestern China ◽  
Cambrian Explosion ◽  
Filamentous Cyanobacteria ◽  
Primary Producers ◽  
Tarim Block ◽  
Eukaryotic Phytoplankton ◽  
History Of ◽  
Wide Geographic Distribution

The basal Cambrian marks the beginning of an important chapter in the history of life. However, most paleontological work on the basal Cambrian has been focused on skeletal animal fossils, and our knowledge about the primary producers—cyanobacteria and eukaryotic phytoplankton (e.g., acritarchs)—is limited. In this research, we have investigated basal Cambrian acritarchs, coccoidal microfossils, and cyanobacteria preserved in phosphorites and cherts of the Yanjiahe Formation in the Yangtze Gorges area (South China) and the Yurtus Formation in the Aksu area (Tarim Block, northwestern China). Our study confirms the occurrence in these two formations of small acanthomorphic acritarchs characteristic of the basal CambrianAsteridium–Comasphaeridium–Heliosphaeridium(ACH) assemblage. These acritarchs include abundantHeliosphaeridium ampliatimi(Wang, 1985) Yao et al., 2005, commonYurtusia uniformisn. gen. and n. sp., and rareComasphaeridium annulare(Wang, 1985) Yao et al., 2005. In addition, these basal Cambrian successions also contain the clustered coccoidal microfossilArchaeophycus yunnanensis(SonginLuo et al., 1982) n. comb., several filamentous cyanobacteria [Cyanonema majusn. sp.,Oscillatoriopsis longaTimofeev and Hermann, 1979, andSiphonophycus robustum(Schopf, 1968) Knoll et al., 1991], and the tabulate tubular microfossilMegathrix longusL. Yin, 1987a, n. emend. Some of these taxa (e.g.,H. ampliatum, C. annulare, andM. longus) have a wide geographic distribution but occur exclusively in basal Cambrian successions, supporting their biostratigraphic importance. Comparison between the stratigraphic occurrences of microfossils reported here and skeletal animal fossils published by others suggests that animals and phytoplankton radiated in tandem during the Cambrian explosion.

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