Two complete specimens from the Pelsonian （Middle Anisian, Middle Triassic） of Luoping, Yunnan Province, South China are referred to a new actinopterygian genus, Luopingichthys gen. nov., and ascribed to the perleid...Two complete specimens from the Pelsonian （Middle Anisian, Middle Triassic） of Luoping, Yunnan Province, South China are referred to a new actinopterygian genus, Luopingichthys gen. nov., and ascribed to the perleidiform family Polzbergidae based especially on a typical synapomorphy of a peculiar premaxillary-maxillary complex, i.e., the fusion between premaxillary and maxillary along the antero-dorsal margin of the maxillary. The new taxon differs from other deep-bodied representatives of the family, Felberia and Stoppania, in its fusiform or deep fusiform body shape; sickle-shaped preopercular with short infraorbital process; lack of modified scales at the base of the anal fin; the short-based dorsal fin; scarcely ornamented scales; and thin anterior teeth. Based on a redescription of the holotype of the taxon Ctenognathichthys hattichi from the Middle Triassic （Ladinian） Prosanto Formation, Canton Graubiinden, eastern Switzerland, the only known specimen, which shows the same fusion between premaxillary and maxillary, the systematic position of the species is clarified and the taxon is proposed to be a further representative of the family Polzbergidae, and is transferred to the new genus.展开更多
To show paleontological characteristics of the Olenekian-Anislan boundary beds in the Russian Far East, a review of new data on the Upper Olenekian and Lower Anisian biostratigraphy of South Primorye is given on the b...To show paleontological characteristics of the Olenekian-Anislan boundary beds in the Russian Far East, a review of new data on the Upper Olenekian and Lower Anisian biostratigraphy of South Primorye is given on the basis of five sections： Golyi Cape, Petrovka River, Zhitkov Peninsula, Tchernyschew Bay and Atlasov Cape, using new ammonoid, brachiopod and conodont findings. The most representative ammonoid assemblage at the base of the Anisian was discovered in the Ussuriphyllites amurensis Zone （10.6 m thick） of the Atlasov Cape Section： Parasageceras sp. nov., Prionitidae gen. et sp. nov. , Ussuriphyllites amurensis （Kiparisova） （dominant）, Megaphyllites atlasoviensis Zakharov, Leiophyllites praematurus Kiparisova, Leiophyllites sp. , Ussurites sp. , Paradanubites sp. indet., Paracrochordiceras sp. nov., Prohungarites popowi Kiparisova, Arctohungarites primoriensis Zakharov, A. solimani （Toula）, Salterites sp. indet. （gigantic shell）, and Tropigastrites sublachontanus Zakharov. Conodonts Neospathodus cf. homeri （Bender） were found in the lower part of the Ussuriphyllites amurensis Zone of the Atlasov Cape. The Atlasov Cape seems to be one of the very promising sections of the Russian Far East for detailed investigation of the Olenekian-Anisian boundary.展开更多
The Olenekian-Anisian Boundary(OAB)interval is an important time in Earth history,reflecting the last phase of marine ecosystem recovery in the aftermath of the end-Permian mass extinction.Despite this,the Global Stra...The Olenekian-Anisian Boundary(OAB)interval is an important time in Earth history,reflecting the last phase of marine ecosystem recovery in the aftermath of the end-Permian mass extinction.Despite this,the Global Stratotype Section and Point(GSSP)for the base of the Anisian remains undefined.The first appearance of the conodont Chiosella timorensis has been proposed as a potential index for the boundary;however,the discovery of this conodont with ammonoids traditionally considered to be Spathian has generated doubts about its suitability.The taxonomy and relationships of early Anisian conodonts,including species of Chiosella,remain understudied,which leads to difficulties in correlation.New species of Neogondolella(N.gradinarui)and Magnigondolella(M.n.sp.D)have been recognized from the leading GSSP candidate section for the OAB at De?li Caira,and from an additional OAB section at Guandao.Furthermore,several species previously identified in Canada and the USA can be recognized from these sections,improving correlation between Tethys and North America.One of these species may serve as a suitable alternative proxy for the OAB;for instance,N.curva appears just below the first Anisian ammonoids in De?li Caira,and just above the first appearance of C.timorensis in both De?li Caira and Guandao.Continued work on sections other than the candidate sections,and on the taxonomy of species outside of those traditionally proposed as indices,is required.展开更多
In this paper,we provide two new Triassic palaeomagnetic poles from Winterswijk,the Netherlands,in the stable interior of the Eurasian plate.They were respectively collected from the Anisian(~247–242 Ma)red marly lim...In this paper,we provide two new Triassic palaeomagnetic poles from Winterswijk,the Netherlands,in the stable interior of the Eurasian plate.They were respectively collected from the Anisian(~247–242 Ma)red marly limestones of the sedimentary transition of the Buntsandstein Formation to the dark grey limestones of the basal Muschelkalk Formation,and from the Rhaetian(~208–201 Ma)shallow marine claystones that unconformably overlie the Muschelkalk Formation.The magnetization is carried by hematite or magnetite in the Anisian limestones,and iron sulfides and magnetite in the Rhaetian sedimentary rocks,revealing for both a large normal polarity overprint with a recent(geocentric axial dipole field)direction at the present latitude of the locality.Alternating field and thermal demagnetization occasionally reveal a stable magnetization decaying towards the origin,interpreted as the Characteristic Remanent Magnetization.Where we find a pervasive(normal polarity)overprint,we can often still determine well-defined great-circle solutions.Our interpreted palaeomagnetic poles include the great-circle solutions.The Anisian magnetic pole has declination D±ΔDx=210.8±3.0°,inclination I±ΔIx=-26.7±4.9°,with a latitude,longitude of 45.0°,142.0°respectively,K=43.9,A95=2.9°,N=56.The Rhaetian magnetic pole has declination D±ΔDx=32.0±8.7°,inclination I±ΔIx=50.9±8.1°,with a latitude,longitude of 60.6°,123.9°respectively,K=19.3,A95=7.4°,N=21.The poles plot close to the predicted location of global apparent polar wander paths(GAPWa Ps)in Eurasian coordinates and are feasible for future apparent polar wander path construction.They confirm that the intracontinental,shallow-marine Germanic Basin,in which the Muschelkalk Formation was deposited,existed at a palaeolatitude of 14.1°[11.3,17.1]N,in a palaeo-environment reminding of the Persian Gulf today.In Rhaetian times,palaeolatitudes of 31.6°[24.8,39.8]N were reached,on its way to the modern latitude of 52°N.展开更多
The present study of Anisian(Middle Triassic)conodonts from the Kocaeli Peninsula(western Turkey)encompasses over 10 species of the families Gondolellidae and Gladigondolellidae,providing Early and Middle Triassic tim...The present study of Anisian(Middle Triassic)conodonts from the Kocaeli Peninsula(western Turkey)encompasses over 10 species of the families Gondolellidae and Gladigondolellidae,providing Early and Middle Triassic time constraints,Chiosella timorensis(Nogami,1968);Cornudina oezdemirae Gedik,1975;Gladigondolella tethydis(Huckriede,1958);Neostrachanognathus tahoensis Koike,1998;Paragondolella aegaea(Bender,1970);Paragondolella bulgarica Budurov and Stefanov,1975;Nicoraella kockeli(Tatge,1956);P.hanbulogi(Sudar and Budurov,1979),and Gladigondolella sp.A.Newly established are Paragondolella hirschii n.sp.Kilic and Budurov;P.praecornuta n.sp.Kilic ,Budurov,Petrunova and Mirauta;and P.ebruae n.sp.K?l??.The Kocaeli Anisian conodonts show a faunal affinity with Bulgaria.The present Anisian fauna is characteristic of the Tethys.The strong homeomorphy that characterizes the Anisian in western North America is discussed.展开更多
盘县新民乡羊圈村及其邻区关岭组上段产出两种混鱼龙:Mixosaurus panxianensis Jiang et al.,2006和Phalarodon cf.P.fraasi Merriam,1910,含混鱼龙类化石层时代应为中三叠世安尼期Pelsonian亚期。"Mixosaurus yangjuanensis Liu a...盘县新民乡羊圈村及其邻区关岭组上段产出两种混鱼龙:Mixosaurus panxianensis Jiang et al.,2006和Phalarodon cf.P.fraasi Merriam,1910,含混鱼龙类化石层时代应为中三叠世安尼期Pelsonian亚期。"Mixosaurus yangjuanensis Liu and Yin,2008"命名所依据的正模标本无关键的头骨特征,选取的头后骨骼做鉴定特征对混鱼龙类种一级分类无意义,鉴定特征所依据的基本骨块存在鉴定错误;"Mixosaurus maotaiensis"的厘定应无效;盘县动物群中无Mixosaurus cornalianus出现。展开更多
Detailed conodont analysis on the Yangjuan-Chupiwa section, Xinmin, Panxian County, Guizhou Province, revealed a conodont sequence including four Anisian conodont zones, viz. Nicoraella germanica Zone, Nc. kockeli Zon...Detailed conodont analysis on the Yangjuan-Chupiwa section, Xinmin, Panxian County, Guizhou Province, revealed a conodont sequence including four Anisian conodont zones, viz. Nicoraella germanica Zone, Nc. kockeli Zone, Paragondolella bifurcata Zone and Neogondolella constricta Zone. These zones indicate that the upper Guanling Formation consists of strata from the Bithynian to the lllyrian of the Anisian. Appearance of Neogondolella constricta suggests that the Anisian/Ladinian boundary might be in the overlying Yangliujing Formation. The Panxian Fauna with well-preserved marine reptile and fish fossils is proved to belong to the lower part of the conodont Nc. kockeli Zone in the studied area. Thus, the age of the Panxian Fauna could be the early Pelsonian of the Anisian.展开更多
The Middle Triassic Panxian fauna is a physical marker and representative record of the rapid recovery of the Triassic marine ecosystem following the Early Triassic stagnant stage after the end-Permian mass extinction...The Middle Triassic Panxian fauna is a physical marker and representative record of the rapid recovery of the Triassic marine ecosystem following the Early Triassic stagnant stage after the end-Permian mass extinction. Ten marine reptile taxa have been found from the 1.82-2.10 m-thick fossiliferous level in the Upper Member of the Guanling Formation, which can be subdivided into three marine reptile beds through the analysis on the stratigraphic distributions of fossil reptiles. The Lower Reptile Bed yields the sauropterygians Placodus inexpectatus Jiang et al., 2008 and Lariosaurus hongguoensis Jiang et al., 2006, the ichthyopterygians Xinminosaurus catactes Jiang et al., 2008 and Phalarodon cf. Phalarodon fraasi Merriam, 1910, associated with Mixosaurus panxianensis Jiang et al., 2006, representing a stage of predominance of durophagous taxa. In this bed, the large complete skeletons may reach up to 2.3 m in length, and lithofacies and chemostratigraphic analyses indicate a relatively deep carbonate platform with an oxic water environment near the bottom, as well as a rising sea level The Middle Reptile Bed yields the sauropterygian Nothosaurus yangjuanensis Jiang et al., 2006 and the archosaur Qianosuchus mixtus Li et al., 2006, associated with Mixosaurus panxianensis Jiang et al., 2006. The fossils in this bed are characterized by its pincering dentition and large overall body size, with the largest possibly exceeding 3 m in length. This bed might represent a time of deepest basin with relatively anoxic condition near the bottom. The Upper Reptile Bed yields the sauropterygians Wumengosaurus delicatomandibularis Jiang et al., 2008, Keichousaurus sp., the protorosaur Dinocephalosaurus orientalis Li, 2003, and the ichthyopterygian Mixosaurus panxianensis Jiang et al., 2006. In this bed, reptilian taxa characterized by suction feeding appeared, and most are less than 1 m long. This bed corresponds to a period of decreasing water depth.展开更多
基金supported by Peking University and NSFC(grant 40702001)by a grant from UNIMI Chancellorand FIRST funds for the Italian team
文摘Two complete specimens from the Pelsonian （Middle Anisian, Middle Triassic） of Luoping, Yunnan Province, South China are referred to a new actinopterygian genus, Luopingichthys gen. nov., and ascribed to the perleidiform family Polzbergidae based especially on a typical synapomorphy of a peculiar premaxillary-maxillary complex, i.e., the fusion between premaxillary and maxillary along the antero-dorsal margin of the maxillary. The new taxon differs from other deep-bodied representatives of the family, Felberia and Stoppania, in its fusiform or deep fusiform body shape; sickle-shaped preopercular with short infraorbital process; lack of modified scales at the base of the anal fin; the short-based dorsal fin; scarcely ornamented scales; and thin anterior teeth. Based on a redescription of the holotype of the taxon Ctenognathichthys hattichi from the Middle Triassic （Ladinian） Prosanto Formation, Canton Graubiinden, eastern Switzerland, the only known specimen, which shows the same fusion between premaxillary and maxillary, the systematic position of the species is clarified and the taxon is proposed to be a further representative of the family Polzbergidae, and is transferred to the new genus.
文摘To show paleontological characteristics of the Olenekian-Anislan boundary beds in the Russian Far East, a review of new data on the Upper Olenekian and Lower Anisian biostratigraphy of South Primorye is given on the basis of five sections： Golyi Cape, Petrovka River, Zhitkov Peninsula, Tchernyschew Bay and Atlasov Cape, using new ammonoid, brachiopod and conodont findings. The most representative ammonoid assemblage at the base of the Anisian was discovered in the Ussuriphyllites amurensis Zone （10.6 m thick） of the Atlasov Cape Section： Parasageceras sp. nov., Prionitidae gen. et sp. nov. , Ussuriphyllites amurensis （Kiparisova） （dominant）, Megaphyllites atlasoviensis Zakharov, Leiophyllites praematurus Kiparisova, Leiophyllites sp. , Ussurites sp. , Paradanubites sp. indet., Paracrochordiceras sp. nov., Prohungarites popowi Kiparisova, Arctohungarites primoriensis Zakharov, A. solimani （Toula）, Salterites sp. indet. （gigantic shell）, and Tropigastrites sublachontanus Zakharov. Conodonts Neospathodus cf. homeri （Bender） were found in the lower part of the Ussuriphyllites amurensis Zone of the Atlasov Cape. The Atlasov Cape seems to be one of the very promising sections of the Russian Far East for detailed investigation of the Olenekian-Anisian boundary.
文摘The Olenekian-Anisian Boundary(OAB)interval is an important time in Earth history,reflecting the last phase of marine ecosystem recovery in the aftermath of the end-Permian mass extinction.Despite this,the Global Stratotype Section and Point(GSSP)for the base of the Anisian remains undefined.The first appearance of the conodont Chiosella timorensis has been proposed as a potential index for the boundary;however,the discovery of this conodont with ammonoids traditionally considered to be Spathian has generated doubts about its suitability.The taxonomy and relationships of early Anisian conodonts,including species of Chiosella,remain understudied,which leads to difficulties in correlation.New species of Neogondolella(N.gradinarui)and Magnigondolella(M.n.sp.D)have been recognized from the leading GSSP candidate section for the OAB at De?li Caira,and from an additional OAB section at Guandao.Furthermore,several species previously identified in Canada and the USA can be recognized from these sections,improving correlation between Tethys and North America.One of these species may serve as a suitable alternative proxy for the OAB;for instance,N.curva appears just below the first Anisian ammonoids in De?li Caira,and just above the first appearance of C.timorensis in both De?li Caira and Guandao.Continued work on sections other than the candidate sections,and on the taxonomy of species outside of those traditionally proposed as indices,is required.
基金funded through NWO Vidi Grant 864.11.004and NWO Vici Grant 865.17.001
文摘In this paper,we provide two new Triassic palaeomagnetic poles from Winterswijk,the Netherlands,in the stable interior of the Eurasian plate.They were respectively collected from the Anisian(~247–242 Ma)red marly limestones of the sedimentary transition of the Buntsandstein Formation to the dark grey limestones of the basal Muschelkalk Formation,and from the Rhaetian(~208–201 Ma)shallow marine claystones that unconformably overlie the Muschelkalk Formation.The magnetization is carried by hematite or magnetite in the Anisian limestones,and iron sulfides and magnetite in the Rhaetian sedimentary rocks,revealing for both a large normal polarity overprint with a recent(geocentric axial dipole field)direction at the present latitude of the locality.Alternating field and thermal demagnetization occasionally reveal a stable magnetization decaying towards the origin,interpreted as the Characteristic Remanent Magnetization.Where we find a pervasive(normal polarity)overprint,we can often still determine well-defined great-circle solutions.Our interpreted palaeomagnetic poles include the great-circle solutions.The Anisian magnetic pole has declination D±ΔDx=210.8±3.0°,inclination I±ΔIx=-26.7±4.9°,with a latitude,longitude of 45.0°,142.0°respectively,K=43.9,A95=2.9°,N=56.The Rhaetian magnetic pole has declination D±ΔDx=32.0±8.7°,inclination I±ΔIx=50.9±8.1°,with a latitude,longitude of 60.6°,123.9°respectively,K=19.3,A95=7.4°,N=21.The poles plot close to the predicted location of global apparent polar wander paths(GAPWa Ps)in Eurasian coordinates and are feasible for future apparent polar wander path construction.They confirm that the intracontinental,shallow-marine Germanic Basin,in which the Muschelkalk Formation was deposited,existed at a palaeolatitude of 14.1°[11.3,17.1]N,in a palaeo-environment reminding of the Persian Gulf today.In Rhaetian times,palaeolatitudes of 31.6°[24.8,39.8]N were reached,on its way to the modern latitude of 52°N.
文摘The present study of Anisian(Middle Triassic)conodonts from the Kocaeli Peninsula(western Turkey)encompasses over 10 species of the families Gondolellidae and Gladigondolellidae,providing Early and Middle Triassic time constraints,Chiosella timorensis(Nogami,1968);Cornudina oezdemirae Gedik,1975;Gladigondolella tethydis(Huckriede,1958);Neostrachanognathus tahoensis Koike,1998;Paragondolella aegaea(Bender,1970);Paragondolella bulgarica Budurov and Stefanov,1975;Nicoraella kockeli(Tatge,1956);P.hanbulogi(Sudar and Budurov,1979),and Gladigondolella sp.A.Newly established are Paragondolella hirschii n.sp.Kilic and Budurov;P.praecornuta n.sp.Kilic ,Budurov,Petrunova and Mirauta;and P.ebruae n.sp.K?l??.The Kocaeli Anisian conodonts show a faunal affinity with Bulgaria.The present Anisian fauna is characteristic of the Tethys.The strong homeomorphy that characterizes the Anisian in western North America is discussed.
文摘盘县新民乡羊圈村及其邻区关岭组上段产出两种混鱼龙:Mixosaurus panxianensis Jiang et al.,2006和Phalarodon cf.P.fraasi Merriam,1910,含混鱼龙类化石层时代应为中三叠世安尼期Pelsonian亚期。"Mixosaurus yangjuanensis Liu and Yin,2008"命名所依据的正模标本无关键的头骨特征,选取的头后骨骼做鉴定特征对混鱼龙类种一级分类无意义,鉴定特征所依据的基本骨块存在鉴定错误;"Mixosaurus maotaiensis"的厘定应无效;盘县动物群中无Mixosaurus cornalianus出现。
基金This study was financially supported by grants from the"985"project of Peking University,National Natural Science Foundation of China(grant 40272005)the Major Basic Research Projects of China(grant G2000077700).
文摘Detailed conodont analysis on the Yangjuan-Chupiwa section, Xinmin, Panxian County, Guizhou Province, revealed a conodont sequence including four Anisian conodont zones, viz. Nicoraella germanica Zone, Nc. kockeli Zone, Paragondolella bifurcata Zone and Neogondolella constricta Zone. These zones indicate that the upper Guanling Formation consists of strata from the Bithynian to the lllyrian of the Anisian. Appearance of Neogondolella constricta suggests that the Anisian/Ladinian boundary might be in the overlying Yangliujing Formation. The Panxian Fauna with well-preserved marine reptile and fish fossils is proved to belong to the lower part of the conodont Nc. kockeli Zone in the studied area. Thus, the age of the Panxian Fauna could be the early Pelsonian of the Anisian.
基金supported bygrants from the National Natural Science Foundation ofChina(no.:40672002 and 40302009)the Program for NewCentury Excellent Talents in University(no.:NCET-07-0015)+1 种基金the Committee for Research and Exploration ofthe National Geographic Society of USA(no.:7886-05)Peking University,and was a contribution to the IGCP-572 project
文摘The Middle Triassic Panxian fauna is a physical marker and representative record of the rapid recovery of the Triassic marine ecosystem following the Early Triassic stagnant stage after the end-Permian mass extinction. Ten marine reptile taxa have been found from the 1.82-2.10 m-thick fossiliferous level in the Upper Member of the Guanling Formation, which can be subdivided into three marine reptile beds through the analysis on the stratigraphic distributions of fossil reptiles. The Lower Reptile Bed yields the sauropterygians Placodus inexpectatus Jiang et al., 2008 and Lariosaurus hongguoensis Jiang et al., 2006, the ichthyopterygians Xinminosaurus catactes Jiang et al., 2008 and Phalarodon cf. Phalarodon fraasi Merriam, 1910, associated with Mixosaurus panxianensis Jiang et al., 2006, representing a stage of predominance of durophagous taxa. In this bed, the large complete skeletons may reach up to 2.3 m in length, and lithofacies and chemostratigraphic analyses indicate a relatively deep carbonate platform with an oxic water environment near the bottom, as well as a rising sea level The Middle Reptile Bed yields the sauropterygian Nothosaurus yangjuanensis Jiang et al., 2006 and the archosaur Qianosuchus mixtus Li et al., 2006, associated with Mixosaurus panxianensis Jiang et al., 2006. The fossils in this bed are characterized by its pincering dentition and large overall body size, with the largest possibly exceeding 3 m in length. This bed might represent a time of deepest basin with relatively anoxic condition near the bottom. The Upper Reptile Bed yields the sauropterygians Wumengosaurus delicatomandibularis Jiang et al., 2008, Keichousaurus sp., the protorosaur Dinocephalosaurus orientalis Li, 2003, and the ichthyopterygian Mixosaurus panxianensis Jiang et al., 2006. In this bed, reptilian taxa characterized by suction feeding appeared, and most are less than 1 m long. This bed corresponds to a period of decreasing water depth.
基金supported bythe grants from the National Natural Science Foundation of China(#40872019) to SQHfromthe Major Basic Research Projects(#2006CB806400) of the Ministry of Science and Technologyof China to SQH,WXC and LC+2 种基金from the Canadian Museum of Nature(R34) to WXCfrom the National Natural Science Foundation(#40772015,40121202) of ChinatheCAS/SAFEA International Partnership Program for Creative Research Teams to LC and WXC~~
