The excellent preservation of the acritarchs, their great abundance, diversity and good stratigraphic control permit establishment of a detailed Middle and Late Cambrian acritarch biozonation. A total of 56 palynomorph species form the basis of 10 local acritarch assemblage zones. Assemblage zones I-II occur in the lower and middle parts of the Member C of the Mila Formation and suggest Early-m...

. Figure 1. Cambrian lobopodian diversity. (A) Aysheaia pedunculata, middle Cambrian Burgess Shale (NMNH-83942). (B) Claws of Aysheaia pedunculata (NMNH-365608). (C) Hallucigenia sparsa, middle Cambrian Burgess Shale (NMNH198658; courtesy of M. Smith, University of Cambridge. Nature 523, 75–78). (D) Microdictyon sinicum, early Cambrian Chengjiang (ELRC-30060; courtesy of G. Edgecombe, Natural H...

a r t i c l e i n f o The Early–Middle Cambrian Pioche Shale of Lincoln County, Nevada preserves a diverse array of soft-bodied ecdysozoans that are well-known from the Burgess Shale soft-bodied fauna of British Columbia, Canada. At Pioche certain genera occur both above and below the Middle Cambrian boundary, allowing a comparison of the nature of their preservation across this interval. In or...

Lobopodians, a nonmonophyletic assemblage of worm-shaped soft-bodied animals most closely related to arthropods, show two major morphotypes: long-legged and short-legged forms. The morphotype with stubby, conical legs has a long evolutionary history, from the early Cambrian through the Carboniferous, including the living onychophorans and tardigrades. Species with tubular lobopods exceeding the...

The Middle Cambrian Spence Shale Member (Langston Formation) and Wheeler and Marjum Formations of Utah are known to contain a diverse soft-bodied fauna, but important new paleontological material continues to be uncovered from these strata. New specimens of anomalocaridids include the largest and smallest near complete examples yet reported from Utah. New material of stem group arthropods inclu...

Burgess Shale-type deposits are renowned for their exquisite preservation of soft-bodied organisms, representing a range of animal body plans that evolved during the Cambrian 'explosion'. However, the rarity of these fossil deposits makes it difficult to reconstruct the broader-scale distributions of their constituent organisms. By contrast, microscopic skeletal elements represent an extensive ...

cambrian sedimentary facies are exposed throughout north part of kerman region. trilobites’ faunas are the most common invertebrate fossils within the cambrian strata. the section is made of 217 m of sandstone, shale, limestone and dolomite. in this study, 153 trilobite samples including seven species and genera were identified from the dahu section 12 km. east of zarand. this trilobite’s assem...

Cambrian sedimentary facies are exposed throughout north part of Kerman region. Trilobites’ faunas are the most common invertebrate fossils within the Cambrian strata. The section is made of 217 m of sandstone, shale, limestone and dolomite. In this study, 153 trilobite samples including seven species and genera were identified from the Dahu section 12 Km. east of Zarand. This trilobite’s assem...

Cnidarians represent an early diverging animal group and thus insight into their origin and diversification is key to understanding metazoan evolution. Further, cnidarian jellyfish comprise an important component of modern marine planktonic ecosystems. Here we report on exceptionally preserved cnidarian jellyfish fossils from the Middle Cambrian (approximately 505 million years old) Marjum Form...

The early–middle Cambrian (Fortunian to Age 4) is characterized by a significant increase in metazoan diversification. Furthermore, this interval is marked by a prominent environmental and ecological expansion of arthropodand echinoderm-rich biotas. Recent redox work has suggested that this shift occurred during stable or decreasing marine oxygen levels, suggesting that these paleobiological an...