The middle Smithian (Early Triassic) ammonoid Arctoceras blomstrandi: conch morphology and ornamentation in relation to stratigraphy
The ammonoid genus Arctoceras (Hyatt) occurs across all palaeolatitudes, and is a key genus for middle Smithian biostratigraphical correlations globally. In this study, intraspecific variations in conch morphology, ornamentation and allometry are examined in relation to stratigraphic position. Arcto...
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Wiley-Blackwell Publishing, Inc.
2021
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Online Access: | https://www.zora.uzh.ch/id/eprint/194357/ https://www.zora.uzh.ch/id/eprint/194357/1/Bolvig_Hansen_et_al_2020_Arcto-2.pdf https://doi.org/10.5167/uzh-194357 https://doi.org/10.1002/spp2.1348 |
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ftunivzuerich:oai:www.zora.uzh.ch:194357 2024-06-23T07:57:05+00:00 The middle Smithian (Early Triassic) ammonoid Arctoceras blomstrandi: conch morphology and ornamentation in relation to stratigraphy Hansen, Bitten B. Bucher, Hugo Schneebeli-Hermann, Elke Hammer, Øyvind 2021-08-01 application/pdf https://www.zora.uzh.ch/id/eprint/194357/ https://www.zora.uzh.ch/id/eprint/194357/1/Bolvig_Hansen_et_al_2020_Arcto-2.pdf https://doi.org/10.5167/uzh-194357 https://doi.org/10.1002/spp2.1348 eng eng Wiley-Blackwell Publishing, Inc. https://www.zora.uzh.ch/id/eprint/194357/1/Bolvig_Hansen_et_al_2020_Arcto-2.pdf doi:10.5167/uzh-194357 doi:10.1002/spp2.1348 urn:issn:2056-2802 info:eu-repo/semantics/openAccess Creative Commons: Attribution 4.0 International (CC BY 4.0) http://creativecommons.org/licenses/by/4.0/ Hansen, Bitten B.; Bucher, Hugo; Schneebeli-Hermann, Elke; Hammer, Øyvind (2021). The middle Smithian (Early Triassic) ammonoid Arctoceras blomstrandi: conch morphology and ornamentation in relation to stratigraphy. Papers in Palaeontology, 7(3):1435-1457. Department of Paleontology 560 Fossils & prehistoric life Journal Article PeerReviewed info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion 2021 ftunivzuerich https://doi.org/10.5167/uzh-19435710.1002/spp2.1348 2024-06-12T00:39:43Z The ammonoid genus Arctoceras (Hyatt) occurs across all palaeolatitudes, and is a key genus for middle Smithian biostratigraphical correlations globally. In this study, intraspecific variations in conch morphology, ornamentation and allometry are examined in relation to stratigraphic position. Arctoceras is the most abundant ammonoid genus in the middle Smithian of Svalbard. Originally, seven Arctoceras species were described from Svalbard. Later, as the importance of intraspecific variation was recognized, six of the Arctoceras species from Svalbard were treated as junior synonyms of Arctoceras blomstrandi (Lindström). Yet, the variations in A. blomstrandi conch morphology remain poorly quantified and the dependence on stratigraphic position, unknown. We quantify the intraspecific variation in conch morphology, ornamentation and allometry in relation to stratigraphy of the Svalbard Arctoceras. The results support the assignment of all Arctoceras morphotypes from Svalbard to a single species A. blomstrandi. The new data allow for an updated species description and open the way for the use in biostratigraphy of the endmember morphology A. blomstrandi var. costatus. We document consistent changes in conch morphology and ornamentation in the studied stratigraphic interval, with a distinct shift towards more evolute and ornate conchs in the top of the interval. The trends in the strength of ornamentation are partly explained by covariation with conch morphology (Buckman's law). The most marked shift in the conch morphology and allometric development of A. blomstrandi coincides with the onset of the positive carbon isotope excursion at the end of the middle Smithian, but pre‐dates the mid–late Smithian cooling of the sea surface. Article in Journal/Newspaper Svalbard University of Zurich (UZH): ZORA (Zurich Open Repository and Archive Hyatt ENVELOPE(-65.833,-65.833,-65.750,-65.750) Svalbard |
institution |
Open Polar |
collection |
University of Zurich (UZH): ZORA (Zurich Open Repository and Archive |
op_collection_id |
ftunivzuerich |
language |
English |
topic |
Department of Paleontology 560 Fossils & prehistoric life |
spellingShingle |
Department of Paleontology 560 Fossils & prehistoric life Hansen, Bitten B. Bucher, Hugo Schneebeli-Hermann, Elke Hammer, Øyvind The middle Smithian (Early Triassic) ammonoid Arctoceras blomstrandi: conch morphology and ornamentation in relation to stratigraphy |
topic_facet |
Department of Paleontology 560 Fossils & prehistoric life |
description |
The ammonoid genus Arctoceras (Hyatt) occurs across all palaeolatitudes, and is a key genus for middle Smithian biostratigraphical correlations globally. In this study, intraspecific variations in conch morphology, ornamentation and allometry are examined in relation to stratigraphic position. Arctoceras is the most abundant ammonoid genus in the middle Smithian of Svalbard. Originally, seven Arctoceras species were described from Svalbard. Later, as the importance of intraspecific variation was recognized, six of the Arctoceras species from Svalbard were treated as junior synonyms of Arctoceras blomstrandi (Lindström). Yet, the variations in A. blomstrandi conch morphology remain poorly quantified and the dependence on stratigraphic position, unknown. We quantify the intraspecific variation in conch morphology, ornamentation and allometry in relation to stratigraphy of the Svalbard Arctoceras. The results support the assignment of all Arctoceras morphotypes from Svalbard to a single species A. blomstrandi. The new data allow for an updated species description and open the way for the use in biostratigraphy of the endmember morphology A. blomstrandi var. costatus. We document consistent changes in conch morphology and ornamentation in the studied stratigraphic interval, with a distinct shift towards more evolute and ornate conchs in the top of the interval. The trends in the strength of ornamentation are partly explained by covariation with conch morphology (Buckman's law). The most marked shift in the conch morphology and allometric development of A. blomstrandi coincides with the onset of the positive carbon isotope excursion at the end of the middle Smithian, but pre‐dates the mid–late Smithian cooling of the sea surface. |
format |
Article in Journal/Newspaper |
author |
Hansen, Bitten B. Bucher, Hugo Schneebeli-Hermann, Elke Hammer, Øyvind |
author_facet |
Hansen, Bitten B. Bucher, Hugo Schneebeli-Hermann, Elke Hammer, Øyvind |
author_sort |
Hansen, Bitten B. |
title |
The middle Smithian (Early Triassic) ammonoid Arctoceras blomstrandi: conch morphology and ornamentation in relation to stratigraphy |
title_short |
The middle Smithian (Early Triassic) ammonoid Arctoceras blomstrandi: conch morphology and ornamentation in relation to stratigraphy |
title_full |
The middle Smithian (Early Triassic) ammonoid Arctoceras blomstrandi: conch morphology and ornamentation in relation to stratigraphy |
title_fullStr |
The middle Smithian (Early Triassic) ammonoid Arctoceras blomstrandi: conch morphology and ornamentation in relation to stratigraphy |
title_full_unstemmed |
The middle Smithian (Early Triassic) ammonoid Arctoceras blomstrandi: conch morphology and ornamentation in relation to stratigraphy |
title_sort |
middle smithian (early triassic) ammonoid arctoceras blomstrandi: conch morphology and ornamentation in relation to stratigraphy |
publisher |
Wiley-Blackwell Publishing, Inc. |
publishDate |
2021 |
url |
https://www.zora.uzh.ch/id/eprint/194357/ https://www.zora.uzh.ch/id/eprint/194357/1/Bolvig_Hansen_et_al_2020_Arcto-2.pdf https://doi.org/10.5167/uzh-194357 https://doi.org/10.1002/spp2.1348 |
long_lat |
ENVELOPE(-65.833,-65.833,-65.750,-65.750) |
geographic |
Hyatt Svalbard |
geographic_facet |
Hyatt Svalbard |
genre |
Svalbard |
genre_facet |
Svalbard |
op_source |
Hansen, Bitten B.; Bucher, Hugo; Schneebeli-Hermann, Elke; Hammer, Øyvind (2021). The middle Smithian (Early Triassic) ammonoid Arctoceras blomstrandi: conch morphology and ornamentation in relation to stratigraphy. Papers in Palaeontology, 7(3):1435-1457. |
op_relation |
https://www.zora.uzh.ch/id/eprint/194357/1/Bolvig_Hansen_et_al_2020_Arcto-2.pdf doi:10.5167/uzh-194357 doi:10.1002/spp2.1348 urn:issn:2056-2802 |
op_rights |
info:eu-repo/semantics/openAccess Creative Commons: Attribution 4.0 International (CC BY 4.0) http://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.5167/uzh-19435710.1002/spp2.1348 |
_version_ |
1802650538437771264 |