An early Late Cambrian trilobite faunule from Kashmir

1986 ◽  
Vol 123 (5) ◽  
pp. 487-492 ◽  
Author(s):  
P. A. Jell
Keyword(s):  
Middle Cambrian ◽  
Late Cambrian ◽  
Cambrian Trilobite ◽  
The Village ◽  
Early Late

AbstractAn early Late Cambrian trilobite faunule of fewer than 20 specimens and including Monkaspis sp. cf. M. serrata Mong, ?Blackwelderia sp. and Cyclolorenzella sp. is recorded from the Trahagam Formation near the village of Trahagam in Hundwara Tehsil, Kashmir, India. The faunule occurs in green shales and provides the first unequivocal Late Cambrian date for sediments in Kashmir; Kashmiri fossil faunas previously ascribed Late Cambrian ages by Reed are now considered Middle Cambrian.

scholarly journals Satunarcus, a new late Cambrian trilobite genus from southernmost Thailand and a reevaluation of the subfamily Mansuyiinae Hupé, 1955

2020 ◽  
Vol 94 (5) ◽  
pp. 867-880
Author(s):  
Shelly J. Wernette ◽  
Nigel C. Hughes ◽  
Paul M. Myrow ◽  
Apsorn Sardsud
Keyword(s):  
North China ◽  
New Genus ◽  
Sedimentary Rocks ◽  
Cladistic Analysis ◽  
New Genus And Species ◽  
Natural Group ◽  
Middle Cambrian ◽  
Current Definition ◽  
Late Cambrian ◽  
Cambrian Trilobite

AbstractThe Ao Mo Lae Formation of the Tarutao Group crops out on Thailand's Tarutao Island and contains a diverse assemblage of late Furongian trilobite taxa, including several endemic forms. This study presents a new genus and species, Satunarcus molaensis, discovered at two locations on the island. A cladistic analysis of the kaolishaniid subfamily Mansuyiinae in light of Satunarcus and similar genera known from across upper Cambrian equatorial Gondwanan rocks suggests that the subfamily is polyphyletic in its current definition, and thus is not a natural group. Separating Mansuyia Sun, 1924 from the other taxa conventionally placed in Mansuyiinae permits recognition of a previously unrecognized monophyletic subfamily Ceronocarinae new subfamily. As established herein, this kaolishaniid subfamily contains Satunarcus n. gen. and all genera previously recognized as Mansuyiinae. with the exception of Mansuyia itself. Ceronocarinae n. subfam. occur in middle Jiangshanian to middle Cambrian Stage 10 sedimentary rocks from Australia, South China, North China, and Sibumasu, with most genera endemic to Australia.UUID: http://zoobank.org/618c5136-73f0-4912-a7d3-e56559d2a76c

Biostratigraphic significance and paleogeographic implications of Cambrian fossils from a deep core, Warren County, Ohio

1994 ◽  
Vol 68 (1) ◽  
pp. 24-30 ◽  
Author(s):  
Loren E. Babcock
Keyword(s):  
Trace Fossils ◽  
Inner Shelf ◽  
Middle Cambrian ◽  
Late Cambrian ◽  
Warren County ◽  
Eau Claire ◽  
Early Late

A deep core from Warren County, Ohio, has yielded numerous fossils of Cambrian age. The specimens, which are among the first recorded from Cambrian rocks of Ohio, suggest revisions in the inferred ages of the Eau Claire and Mount Simon Formations in the Cincinnati Arch region. Trilobites indicative of Dresbachian (late Middle Cambrian to early Late Cambrian) and possibly Franconian (Late Cambrian) age are present in the upper Eau Claire Formation. By implication, the underlying Mount Simon Formation must be of earlier Dresbachian age or perhaps older. Identified trilobites from the Eau Claire Formation seem to be characteristic of inner-shelf lithofacies of Laurentia. Other body fossils from the Eau Claire Formation include inarticulate brachiopods and a graptolite. Body fossils in the lower Knox Dolomite include trilobite sclerites and echinoderm ossicles. Trace fossils are present in both units.

scholarly journals Cambrian - Middle Ordovician stratigraphy of the Adams Gletscher region, south-west Peary Land, North Greenland

1979 ◽  
Vol 88 ◽  
pp. 29-39
Author(s):  
J.S Peel
Keyword(s):  
Substantial Part ◽  
Middle Cambrian ◽  
Middle Ordovician ◽  
Late Cambrian ◽  
South West ◽  
Lower Ordovician ◽  
Field Notes ◽  
Early Late ◽  
North Greenland ◽  
Cambrian System

Previous geological descriptions of the Adams Gletscher region (fig. 9) have been given by J. C. Troelsen (unpublished field notes in GGU) and Dawes (1976) - the latter based on a three day reconnaissance during 1975. The sequence contains a much fuller record of the Cambrian system than is present in the geologicaIly better described area near Jørgen Brønlund Fjord to the east (Christie & Peel, 1977; Jepsen, 1971), where only Lower Cambrian strata are present. A sample with trilobites collected by Dawes established the occurrence of Middle Cambrian rocks near Adams Gletscher (Peel in Dawes, 1976), but it would now appear that a substantial part of the sequence is of this age. In addition, the location in 1978 of early Late Cambrian trilobites near the base of a 900 m thick unit overlain by the Wandel Valley Formation of Early-Middle Ordovician age, suggests that the upper sub-division of the Cambrian is also well represented. An unconformity of regional extent separates the Cambrian from the overlying Wandel Valley Formation. This formation maintains the same generallithology at Adams Gletscher as that described by Christie & Peel (1977) to the east, although a tentative lithologicallink to the late Lower Ordovician of western North Greenland is established.

Kunmingaspis(Trilobita) putatively from the Yunling collage, and the Cambrian history of the eastern Himalayan syntaxial region

2002 ◽  
Vol 76 (4) ◽  
pp. 709-717 ◽  
Author(s):  
Nigel C. Hughes ◽  
Peng Shanchi ◽  
Luo Huilin
Keyword(s):  
Structural Complexity ◽  
Yangtze Platform ◽  
Tectonic Event ◽  
Middle Cambrian ◽  
Late Cambrian ◽  
History Of ◽  
Cambrian Trilobite ◽  
Critical Constraints ◽  
The Himalaya ◽  
Tethyan Himalaya

Faunal data provide critical constraints upon tectonic models, particularly in such areas of extreme structural complexity as the region adjacent to the eastern syntaxis of the Himalaya. Trilobites reported to have been collected from the Yunling collage at Yinchangou, northwestern Yunnan, are here assigned toKunmingaspis yunnanensisChang, 1964, and the concept of the genusKunmingaspisis reconsidered. Although there is debate about to the paleogeographic affinities of the Yunling collage, the apparent presence of this species supports previous arguments for faunal links between the Yangtze platform and the Himalayan margin during Early and Middle Cambrian time. A significant tectonic event of Late Cambrian/Early Ordovician age present in the western central Himalayan margin suggests that the Lhasa block collided with India at that time, but the northward extent of that block remains unclear. The recently discovered Late Cambrian trilobite fauna of Bhutan may hold the key to establishing faunal relationships between the Tethyan Himalaya, Sibumasu, and the Yangtze platform during this interval. No Cambrian sedimentary rocks are yet known from the Lhasa or Qiangtang blocks of Tibet and so there is no direct evidence for the existence of Cimmeria during the Cambrian Period.

scholarly journals A Balto-Scandian Middle Cambrian fauna from Peary Land, North Greenland

1988 ◽  
Vol 137 ◽  
pp. 118-118
Author(s):  
T.P Fletcher ◽  
A.K Higgins ◽  
J.S Peel
Keyword(s):  
North America ◽  
Field Work ◽  
First Record ◽  
Geological Survey ◽  
Northern Coast ◽  
Middle Cambrian ◽  
The Pacific ◽  
Cambrian Trilobite ◽  
Inland Ice ◽  
North Greenland

The first record of Middle Cambrian faunas of 'Atlantic' affinity from the Franklinian basin sequence of North Greenland was made by Poulsen (1969) who noted that previously described Greenland faunas were of 'Pacific' type. Field work by the Geological Survey of Greenland during the last decade has established that 'Atlantic' faunas are widespread in more outer shelfsequences along the northern coast of North Greenland while the 'Pacific' faunas occur within inner shelfsequences more to the south, near the margin of the Inland Ice. North Greenland preserves both faunas in dose geographical juxtaposition in only slightly tectonised geological settings. Thus, alatest Middle Cambrian trilobite fauna described by Robison (in press) from the Holm Dal Formation in an area some 40 km south of the presently discussed locality (and more inner shelf) includes a mixture of polymeroids characteristic of the Cedaria Zone of North America and agnostoids characteristic of the Lejopyge laevigata Zone of the Swedish standard zonation.

scholarly journals Unexpectedly curved spines in a Cambrian trilobite: considerations on the spinosity in Kingaspidoides spinirecurvatus sp. nov. from the Anti-Atlas, Morocco, and related Cambrian ellipsocephaloids

PalZ ◽  
2020 ◽  
Vol 94 (4) ◽  
pp. 645-660
Author(s):  
Gerd Geyer ◽  
Miguel Caldeira Pais ◽  
Thomas Wotte
Keyword(s):  
The Body ◽  
Body Posture ◽  
Protective Device ◽  
Experimental Phase ◽  
Middle Cambrian ◽  
Forest Region ◽  
Spine Development ◽  
Axial Ring ◽  
Cambrian Trilobite ◽  
Segment 8

Abstract The new ellipsocephaloid trilobite species Kingaspidoides spinirecurvatus has a spectacular morphology because of a unique set of two long and anteriorly recurved spines on the occipital ring and the axial ring of thoracic segment 8. Together with the long genal spines this whimsical dorsally directed spine arrangement is thought to act as a non-standard protective device against predators. This is illustrated by the body posture during different stages of enrolment, contrasting with the more sophisticated spinosities seen in later trilobites, which are discussed in brief. Kingaspidoides spinirecurvatus from the lower–middle Cambrian boundary interval of the eastern Anti-Atlas in Morocco has been known for about two decades, with specimens handled as precious objects on the fossil market. Similar, but far less spectacular, spine arrangements on the thoracic axial rings are known from other ellipsocephaloid trilobites from the Anti-Atlas of Morocco and the Franconian Forest region of Germany. This suggests that an experimental phase of spine development took place within the Kingaspidoides clade during the early–middle Cambrian boundary interval.

scholarly journals Reconstruction of the enigmatic Late Cambrian Climactichnites

1992 ◽  
Vol 6 ◽  
pp. 321-321 ◽  
Author(s):  
E.L. Yochelson ◽  
M. Parrish
Keyword(s):  
New York ◽  
Cross Section ◽  
Individual Variation ◽  
Short Distance ◽  
Loose Sand ◽  
Desiccation Cracks ◽  
Late Cambrian ◽  
Anterior Flap ◽  
Considerable Individual Variation ◽  
Early Late

Climactichnites Logan, 1860, is known only from its large trail up to 20 cm in width, a trace superficially resembling a rope ladder. Prominent lateral ridges are parallel throughout the length of the trail; they may be smooth and hemispherical in cross-section or crenulated, much like a pie crust. Between these ridges is a series of raised dune-like bars and furrows dug into the substrate. The bars and furrows show considerable individual variation between trails and also variation along a trail. Ovoid impressions are known which occur at the start of trails. The posterior of these impressions is well rounded; the anterior is triangular, and for a short distance from the impression, the trail is developed on only one side. One exceptionally preserved impression shows curved, closely spaced, fine lines parallel to the posterior.The trails are found only in sandstone, and where they are present, they are abundant. Slightly equivocable evidence indicates a Dresbachian (early Late Cambrian) age for the occurrences in New York, Missouri, and Wisconsin; trails in Ontario and Quebec are less certainly dated. Desiccation cracks and air escape hole suggest that the trail was fully exposed to the atmosphere.From this data, a large number of sketches were made to reconstruct an animal able to make such a trail. Each attempt produced new speculation on the morphology. In the final rendition, the animal is bilaterally symmetrical, broad and low. The integument is tough, and the sole bears a subcentral mouth anteriorward. Lateral flaps scraped and compressed damp sand to make the parallel ridges. The anterior was strongly musculated and thin. This anterior flap grasped the sediment, alternating on either side of the animal to pull the form forward when the lateral flaps were relaxed. Curved rows of cilia on the posterior moved loose sand into dunes between the furrows formed by the anterior flaps.This reconstruction is like that of no other animal known in the Vendian or the Phanerozoic.

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