A new post-early Cambrian archaeocyath from Antarctica
Abstract A new species of archaeocyath sponge, Dictyocyathus neptunensis , is described from the lower third of the Nelson Limestone of the Neptune Range, Antarctica. Based on the presence of the trilobites Nelsonia schesis and Amphoton oatesi , these strata are interpreted to be mid- to late middle...
Published in: | Geological Magazine |
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Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Cambridge University Press (CUP)
1992
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Subjects: | |
Online Access: | http://dx.doi.org/10.1017/s0016756800019579 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0016756800019579 |
Summary: | Abstract A new species of archaeocyath sponge, Dictyocyathus neptunensis , is described from the lower third of the Nelson Limestone of the Neptune Range, Antarctica. Based on the presence of the trilobites Nelsonia schesis and Amphoton oatesi , these strata are interpreted to be mid- to late middle Cambrian in age. D. neptunensis shows a branching, low integration modular form and a very simple skeletal type. Such an organization is predicted from known morphological trends within the early Cambrian Archaeocyatha. Specimens are not in life position, and probably form part of a storm deposit. The absence of Dictyocyathus from latest early Cambrian (Toyonian) strata worldwide suggests a convergent nature for this highly simplified skeletal type in archaeocyaths. |
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