Fossil embryos from the Middle and Late Cambrian period of Hunan, south China

Nature ◽  
2004 ◽  
Vol 427 (6971) ◽  
pp. 237-240 ◽  
Author(s):  
Xi-ping Dong ◽  
Philip C. J. Donoghue ◽  
Hong Cheng ◽  
Jian-bo Liu
Keyword(s):  
South China ◽  
Late Cambrian ◽  
Middle And Late Cambrian ◽  
Fossil Embryos

New material of three-dimensionally phosphatized and microscopic cycloneuralians from the Cambrian Paibian Stage of South China

2017 ◽  
Vol 92 (1) ◽  
pp. 87-98 ◽  
Author(s):  
Yunhuan Liu ◽  
Qi Wang ◽  
Tiequan Shao ◽  
Huaqiao Zhang ◽  
Jiachen Qin ◽  
...  
Keyword(s):  
New Species ◽  
South China ◽  
Early Cambrian ◽  
Late Cambrian ◽  
New Material ◽  
Western Hunan ◽  
Fossil Embryos

AbstractSome rare microscopic cycloneuralians are present in the Cambrian of South China, represented by Eopriapulites and Eokinorhynchus (both early Cambrian), fossil embryos of Markuelia (middle to late Cambrian), and palaeoscolecids (early to late Cambrian). Among them, palaeoscolecids are relatively diverse and abundant. Here, we describe new material of three-dimensionally phosphatized and microscopic cycloneuralians from the Paibian Stage of Wangcun Lagerstätte, western Hunan, South China. New material includes fossil embryos assignable to Markuelia sp., two other types of fossil embryos, and three species of palaeoscolecids, including Dispinoscolex decorus Duan, Dong, and Donoghue, 2012, Schistoscolex hunanensis Duan, Dong, and Donoghue, 2012, and Austroscolex sinensis new species. The palaeoscolecid fragments differ mainly in size and armor of the trunk annuli. Since Eokinorhynchus and Eopriapulites occurred the earliest among the Cambrian cycloneuralians, it is proposed here that: (1) cycloneuralians originated in the Cambrian Fortunian small shelly faunas rather than in the early Cambrian macrobenthos, (2) ancestral cycloneuralians may have simple trunk armor, and (3) Eopriapulites represents an ancestral cycloneuralian.

Distinguishing Earth’s oldest known bryozoan (Pywackia, late Cambrian) from pennatulacean octocorals (Mesozoic–Recent)

2015 ◽  
Vol 89 (2) ◽  
pp. 292-317 ◽  
Author(s):  
Ed Landing ◽  
Jonathan B. Antcliffe ◽  
Martin D. Brasier ◽  
Adam B. English
Keyword(s):  
South China ◽  
Late Cambrian ◽  
Stem Group ◽  
Irregular Form ◽  
Highly Evolved

AbstractBryozoans and all biomineralized metazoan phyla extend back into the Cambrian.PywackiaLanding, 2010 is confirmed as a secondarily phosphatized, late Cambrian stenolaemate bryozoan with colonial habit; mineralized zooarium (originally calcareous); granular/rarely granular-prismatic histology of its trilamellar walls; and polymorphism shown by deep autozooecia with diaphragms and hemiphragms, axial zooecia with diaphragms, and probable nanozooecia. The irregular form ofPywackiareflects growth as a 14-hedron that could not branch and a lack of structures such as thickened walls or styles that maintain regular autozooecial spacing in later stenolaemates.Pywackiais a stem group stenolaemate with a stolon modified into a budding axial zooid and autozooid budding. It is morphologically simpler than the highly evolved late Tremadocian bryozoans of South China with features such as styles, cystiphragms, thickened zooecial walls, and massive or branching colonies. As with some bryozoans,Pywackialacks holdfasts but has lineated living chambers and variably sized autozooecia. The late Cambrian origin of bryozoans, euconodonts, polyplacophorans, and cephalopods set the stage for the Ordovician Radiation’s complex communities.Pywackiais not a pennatulacean octocoral. It lacks both a pennatulacean axial rod histology and a budding zooid that remains confluent with daughter autozooids. Indeed,Pywackiawalled off its axial zooid. Similarity of the 6- and 12-sidedPywackiazooarium with circular to 4-sided pennatulacean axes only includes calcareous composition and the general shapes ofPywackiazooaria and someLituariaaxial rods. The pennatulacean record does not extend from the Mesozoic into the Cambrian, and early cnidarians were not phosphatic. The diagnosis ofPywackiais modified.

scholarly journals Cambrian Bradoriida and Phosphatocopida (Arthropoda) of the former Soviet Union

1997 ◽  
Vol 16 (2) ◽  
pp. 179-191 ◽  
Author(s):  
Ludmila M. Melnikova ◽  
David J. Siveter ◽  
Mark Williams
Keyword(s):  
Soviet Union ◽  
Former Soviet Union ◽  
Minor Component ◽  
Leningrad Region ◽  
The Urals ◽  
Late Cambrian ◽  
Central Asian ◽  
Early Palaeozoic ◽  
A Minor ◽  
Middle And Late Cambrian

Abstract. Some 40 bradoriid and phosphatocopid (Arthropoda) species are known from the Cambrian of the former Soviet Union. The faunas occur chiefly in Asia (mostly Siberia and Kazakhstan; also Kirghizia); west of the Urals bradoriid and phosphatocopid faunas are sparse, occurring in the Leningrad region, Belarus and Estonia. Most specimens are recovered as crack-out material from clastic and impure carbonate rocks; acid resistant valves from limestones are a minor component of the known faunas.Early Cambrian (Atdabanian-Botomian) faunas are widespread; middle and late Cambrian faunas are scarcer and are known largely from Siberia and Kazakhstan. Though many species are seemingly short-ranging, currently most have only local biostratigraphic significance, with only a few having practical international correlative value.Palaeogeographically, faunas west of the Urals show affinites with those of the Early Palaeozoic Baltica and Avalonia palaeocontinents (Olenellid trilobite realm). Siberian and central Asian (Kazakhstan, Kirghizia, Gorny–Altay–Mongolian belt) faunas show clear affinities with those of palaeocontinental South China and eastern Gondwana (Redlichiid trilobite realm).

scholarly journals New Cambrian faunas from Peary Land, eastern North Greenland

1979 ◽  
Vol 91 ◽  
pp. 29-36
Author(s):  
A.R Palmer ◽  
J.S Peel
Keyword(s):  
Lower Cambrian ◽  
Early Cambrian ◽  
Middle Cambrian ◽  
Late Cambrian ◽  
Middle And Late Cambrian ◽  
North Greenland

Early, Middle and Late Cambrian faunas from Peary Land, eastern North Greenland, are briefly documented. The Early Cambrian faunas of the lower Brønlund Fjord Group are assigned to the Bonnia-Olenellus Zone, although olenellids from the underiying Buen Formation may be older. Strata from the upper Brønlund Fjord Group with Middle Cambrian faunas are seemingly separated from the Lower Cambrian by a discontinuity, without representation of early Middle Cambrian zones. Faunas from lower beds of the overlying Tavsens Iskappe Group span the Middle-Late Cambrian boundary. Upper beds ofthe Tavsens Iskappe Group are assigned to the Late Cambrian, but corroborative faunal evidence is not yet available.

Diverse radial symmetry among the Cambrian Fortunian fossil embryos from northern Sichuan and southern Shaanxi provinces, South China

Palaeoworld ◽  
2019 ◽  
Vol 28 (3) ◽  
pp. 225-233 ◽  
Author(s):  
Xiao-Feng Xian ◽  
Hua-Qiao Zhang ◽  
Yun-Huan Liu ◽  
Ya-Nan Zhang
Keyword(s):  
South China ◽  
Radial Symmetry ◽  
Southern Shaanxi ◽  
Fossil Embryos

Latest Middle Cambrian metazoan reef from northern Iran

1995 ◽  
Vol 132 (4) ◽  
pp. 367-373 ◽  
Author(s):  
B. Hamdi ◽  
A. Yu. Rozanov ◽  
A. Yu. Zhuravle
Keyword(s):  
Northern Iran ◽  
Middle Cambrian ◽  
Middle Ordovician ◽  
Late Cambrian ◽  
The Family ◽  
Middle And Late Cambrian

AbstractMiddle and Late Cambrian reefs were built mainly by cyanobacterial communities. A few reefs with a metazoan as well as an algal component, however, are known from this interval. A Middle Cambrian reef formed primarily by spicular demosponges is described here from the Mila Formation in the Elburz Mountains, northern Iran. The reef is enclosed within calcareous grainstones which contain terminal Middle Cambrian (late Mayan) trilobites. The Mila Formation reef was constructed by sponges of the family Anthaspidellidae and bacterial (algal?) sheaths, and is the earliest metazoan reef to be documented from the interval after the demise of archaeocyath sponges. The reefal community is typical of subsequent reefal communities of Early–Middle Ordovician age. The Ordovician examples differ only by the incorporation of additional metazoan elements.

Sign in / Sign up

Export Citation Format

Share Document