Aysheaia Prolata from the Utah Wheeler Formation (Drumian, Cambrian) Is a Frontal Appendage of the Radiodontan Stanleycaris

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Aysheaia prolata from the Utah Wheeler Formation (Drumian, Cambrian) is a frontal appendage of the radiodontan Stanleycaris Stephen Pates, Allison C. Daley, and Javier Ortega-Hernández Acta Palaeontologica Polonica 62 (3), 2017: 619-625 doi:https://doi.org/10.4202/app.00361.2017 Aysheaia prolata, was described as the only lobopodian from the Drumian (Cambrian) Wheeler Formation in Utah, USA, and the sole representative of this genus besides the type species Aysheaia pedunculata, from the Cambrian (Stage 5) Stephen Formation, British Columbia. A redescription of Aysheaia prolata reveals previously overlooked morphological features, including segmental boundaries between putative lobopods, and curved terminal spines on the putative anterior end. These observations undermine lobopodian affinities of Aysheaia prolata , and instead we interpret this specimen as an isolated radiodontan frontal appendage. The presence of 11 podomeres, five of which possess elongate and anteriorly recurved ventral blades with auxiliary spines, together with shorter robust dorsal spines, identify the specimen as Stanleycaris. This represents the first report of Stanelycaris outside of the Cambrian Stage 5 thin Stephen Formation in British Columbia, expanding its palaeobiogeographic and stratigraphic range. Aysheaia is left as a monotypic genus endemic to the Burgess Shale. The Spence Shale luolishaniid Acinocrinus stichus is currently the only lobopodian known from the Cambrian of Utah. Key words: Euarthropoda, Radiodonta, Hurdiidae, Cambrian, USA. Stephen Pates [[email protected]], Department of Zoology, University of Oxford, Oxford, OX1 3PS, UK. Allison C. Daley [[email protected]], Institute of Earth Sciences, University of Lausanne, Géopolis, CH-1015, Lausanne, Switzerland. Javier Ortega-Hernández [[email protected]], Department of Zoology, Downing Street, University of Cambridge, Cambridge, CB2 3EJ, UK. This is an open-access article distributed under the terms of the Creative Commons Attribution License (for details please see creativecommons.org), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Full text (1,105.8 kB) Powered by TCPDF (www.tcpdf.org).

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Appendix 3.Pdf
A Geoconservation perspective on the trace fossil record associated with the end – Ordovician mass extinction and glaciation in the Welsh Basin Item Type Thesis or dissertation Authors Nicholls, Keith H. Citation Nicholls, K. (2019). A Geoconservation perspective on the trace fossil record associated with the end – Ordovician mass extinction and glaciation in the Welsh Basin. (Doctoral dissertation). University of Chester, United Kingdom. Publisher University of Chester Rights Attribution-NonCommercial-NoDerivatives 4.0 International Download date 26/09/2021 02:37:15 Item License http://creativecommons.org/licenses/by-nc-nd/4.0/ Link to Item http://hdl.handle.net/10034/622234 International Chronostratigraphic Chart v2013/01 Erathem / Era System / Period Quaternary Neogene C e n o z o i c Paleogene Cretaceous M e s o z o i c Jurassic M e s o z o i c Jurassic Triassic Permian Carboniferous P a l Devonian e o z o i c P a l Devonian e o z o i c Silurian Ordovician s a n u a F y r Cambrian a n o i t u l o v E s ' i k s w o Ichnogeneric Diversity k p e 0 10 20 30 40 50 60 70 S 1 3 5 7 9 11 13 15 17 19 21 n 23 r e 25 d 27 o 29 M 31 33 35 37 39 T 41 43 i 45 47 m 49 e 51 53 55 57 59 61 63 65 67 69 71 73 75 77 79 81 83 85 87 89 91 93 Number of Ichnogenera (Treatise Part W) Ichnogeneric Diversity 0 10 20 30 40 50 60 70 1 3 5 7 9 11 13 15 17 19 21 n 23 r e 25 d 27 o 29 M 31 33 35 37 39 T 41 43 i 45 47 m 49 e 51 53 55 57 59 61 c i o 63 z 65 o e 67 a l 69 a 71 P 73 75 77 79 81 83 n 85 a i r 87 b 89 m 91 a 93 C Number of Ichnogenera (Treatise Part W)
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Discussion Acta Palaeontologica Polonica 63 (1): 105– 110, 2018
Discussion Acta Palaeontologica Polonica 63 (1): 105– 110, 2018 Reply to Comment on “Aysheaia prolata from the Utah Wheeler Formation (Drumian, Cambrian) is a frontal appendage of the radiodontan Stanleycaris” with the formal description of Stanleycaris STEPHEN PATES, ALLISON C. DALEY, and JAVIER ORTEGA-HERNÁNDEZ As part of a comprehensive examination of all radiodontans extend beyond the fossil margins into the rock matrix, demon- from Cambrian localities in the USA, Pates et al. (2017a, b) strating that they are not part of the fossil specimen. and Pates and Daley (2017) revised the taxonomic affinities of several described specimens. This included the reinter- Antenniform frontal appendage.—There are no features that distinguish the structure regarded by Gámez Vintaned et al. pretation of two putative lobopodians, one from the Wheeler (2011) as an antenniform limb, and the interpretation of this Formation (Utah, USA) and one from the Valdemiedes For- feature as a small burrow is more compelling as it extends into mation (Spain), as frontal appendages of the radiodontan the surrounding matrix. Structures identified as “pores” are like- genera Stanleycaris and Caryosyntrips respectively. In their ly plucked mineral grains approximately aligned in this region, comment, Gámez Vintaned and Zhuravlev (2018) disagree and other unaligned voids can be seen elsewhere in the SEM with these conclusions and raise three topics for discussion: images (Gámez Vintaned et al. 2011: fig. 12.5h, k). (i) anatomical features they suggest support a lobopodian affinity for “Mureropodia”; (ii) the identity of Caryosyntrips Proboscis with retractor-protractor muscle system.—The as a radiodontan, and the assignment of certain specimens to presence of a fleshy proboscis among lobopodians has only been this genus; and (iii) the nomenclatural status of Stanleycaris reliably documented in the Chengjiang Onychodictyon ferox (Ou hirpex as an invalid taxon.
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Aysheaia Prolata from the Utah Wheeler Formation (Drumian, Cambrian) Is a Frontal Appendage of the Radiodontan Stanleycaris
Aysheaia prolata from the Utah Wheeler Formation (Drumian, Cambrian) is a frontal appendage of the radiodontan Stanleycaris STEPHEN PATES, ALLISON C. DALEY, and JAVIER ORTEGA-HERNÁNDEZ Pates, S., Daley, A.C., and J. Ortega-Hernández, J. 2017. Aysheaia prolata from the Utah Wheeler Formation (Drumian, Cambrian) is a frontal appendage of the radiodontan Stanleycaris. Acta Palaeontologica Polonica 62 (3): 619–625. Aysheaia prolata, was described as the only lobopodian from the Drumian (Cambrian) Wheeler Formation in Utah, USA, and the sole representative of this genus besides the type species Aysheaia pedunculata, from the Cambrian (Stage 5) Stephen Formation, British Columbia. A redescription of Aysheaia prolata reveals previously overlooked morphological features, including segmental boundaries between putative lobopods, and curved terminal spines on the putative anterior end. These observations undermine lobopodian affinities of Aysheaia prolata, and instead we interpret this specimen as an isolated radiodontan frontal appendage. The presence of 11 podomeres, five of which possess elongate and anteri- orly recurved ventral blades with auxiliary spines, together with shorter robust dorsal spines, identify the specimen as Stanleycaris. This represents the first report of Stanelycaris outside of the Cambrian Stage 5 thin Stephen Formation in British Columbia, expanding its palaeobiogeographic and stratigraphic range. Aysheaia is left as a monotypic genus endemic to the Burgess Shale. The Spence Shale luolishaniid Acinocrinus stichus is currently the only lobopodian known from the Cambrian of Utah. Key words: Euarthropoda, Radiodonta, Hurdiidae, Cambrian, United States. Stephen Pates [[email protected]], Department of Zoology, University of Oxford, Oxford, OX1 3PS, UK. Allison C. Daley [[email protected]], Institute of Earth Sciences, University of Lausanne, Géopolis, CH-1015, Lausanne, Switzerland.
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