comment on this calibration
Cnidaria
| node name Cnidaria Look for this name in NCBI Wikipedia Animal Diversity Web | ||
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recommended citations http://palaeo-electronica.org/content/fc-1 Benton et al. 2015 |
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node minimum age 529 Ma Olivooides multisulcatus co-occurs with Anabarites trisulcatus, which is indicative of the middle of the Fortunian Stage of the Terreneuvian Series, the first of the Cambrian. The top of the Fortunian Stage is dated at 529.0 Ma (Peng et al., 2012). | ||
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node maximum age 636.1 Ma A soft maximum constraint is based on the maximum age interpretation of the Lantian Biota (Yuan et al., 2011). This, together with the Doushantuo Biota (Yuan et al., 2002), provide a series of Lagerstätten preserving the biota in Orsten- and Burgess Shale-like modes of fossilization. None of these Lagerstätten, least of all the Lantian, preserves anything that could possibly be interpreted as even a total group eumetazoan and on this basis we define our soft maximum constraint at 635.5 Ma ± 0.6 Myr (Condon et al., 2005) and, thus, 636.1 Ma. | ||
| primary fossil used to date this node | ||
GMPKU 3083 | ||
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phylogenetic justification
Olivooides is known from embryonic and post-embryonic stages of development, including a polyp theca, characteristic of scyphozoans, and a medusa stage (Dong et al., 2013). |
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phylogenetic reference(s)
Dong, X.-P., Cunningham, J.A., Bengtson, S., Thomas, C.-W., Liu, J.-B., Stampanoni, M., and Donoghue, P.C.J. 2013. Embryos, polyps and medusae of the early Cambrian scyphozoan Olivooides. Proceedings of the Royal Society B: Biological Sciences, 280(2
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| tree image (click image for full size) | ||
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Figure 1 from Benton et al. (2014).
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