An Edgewood-type Hirnantian fauna from the Mackenzie Mountains, northwestern margin of Laurentia
Abstract Silicified brachiopods from Hirnantian strata in three sections of the lower Whittaker Formation, Mackenzie Mountains, northwestern Canada, yielded a moderately diverse, Edgewood-type Hirnantian fauna, consisting of 13 species: Biparetis paucirugosus , Brevilamnulella laevis , Dalmanella ed...
| Published in: | Journal of Paleontology |
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| Main Authors: | , |
| Other Authors: | |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
Cambridge University Press (CUP)
2024
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| Subjects: | |
| Online Access: | http://dx.doi.org/10.1017/jpa.2023.87 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022336023000872 |
| Summary: | Abstract Silicified brachiopods from Hirnantian strata in three sections of the lower Whittaker Formation, Mackenzie Mountains, northwestern Canada, yielded a moderately diverse, Edgewood-type Hirnantian fauna, consisting of 13 species: Biparetis paucirugosus , Brevilamnulella laevis , Dalmanella edgewoodensis , Drabovia noixella , Eospirigerina putilla , Epitomyonia paucitropida , Epitomyonia sekwiensis , Glyptorthis papillosa new species, Gnamptorhynchos orbiculoidea , Katastrophomena mackenzii new species, K . parvicardinis , Parastrophina cf. P . minor , and Skenidioides sp. Compared to the typical Edgewood fauna of the American Midcontinent, Brevilamnulella laevis has a notably smaller shell than B . thebesensis , and is interpreted as a deeper-water form. The strong faunal affinity of the Mackenzie Mountains fauna to the Edgewood-type Hirnantian fauna is indicated by the occurrence of Biparetis , Brevilamnulella , Eospirigerina , and Gnamptorhynchos . In addition to the Edgewood type area within Laurentia, Biparetis , Eospirigerina , and Gnamptorhynchos are characteristic taxa that also occur in the Ellis Bay Formation (Hirnantian) of Anticosti Island. Multivariate and network analyses strongly support the differentiation between an Edgewood-type Hirnantian fauna in Laurentia and peri-Laurentia and the typical Hirnantia fauna of the Kosov Province in Gondwana, peri-Gondwana, South China, Kazakhstan terranes, Avalonia, and Baltica. UUID: http://zoobank.org/7ff8f8c8-52d1-4527-acae-9bacd2e8b914 |
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