comment on this calibration
Atlantogenata
Lineage (NCBI):
root
» Eukaryota
» Opisthokonta
» Metazoa
» Eumetazoa
» Bilateria
» Coelomata
» Deuterostomia
» Chordata
» Craniata <chordata>
» Vertebrata <Metazoa>
» Gnathostomata <vertebrate>
» Euteleostomi
» Sarcopterygii
» Tetrapoda
» Amniota
» Mammalia
» Theria <Mammalia>
» Eutheria
| node name Atlantogenata 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 56 Ma The minimum age estimate is based on the occurrence of Eritherium in the Sidi Chennane quarries, phosphate bed IIa, lower bone-bed, Ouled Abdoun Basin of Morocco, regarded as upper Paleocene (early Thanetian; Gheerbrant, 2009), whose upper bound is dated as 56.0 Ma ± 0.0 Myr (Gradstein et al., 2012). | ||
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node maximum age 164.6 Ma The soft maximum date is based on the divergence of Eutheria from other mammals in the late Jurassic, represented by Juramaia (Luo et al., 2011). This taxon is represented in the Daxigou site of the Tiaojishan Formation, Liaoning Province, Northeastern China, and has been constrained by radiometric dates to derive from deposits of just over 160 Ma in age (Luo et al., 2011). The equivalent marine stage is the Oxfordian (Gradstein et al., 2012), with a lower boundary of 163.5 Ma ± 1.1 Myr, and thus 164.6 Ma is a soft maximum. | ||
| primary fossil used to date this node | ||
MNHNFr PM69 | ||
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phylogenetic justification
Eritherium is classed as a proboscidean based on numerous dental and cranial synapomorphies (Gheerbrant, 2009): I1 enlarged, larger than I2, I1–2 with high (styliform), labio-lingually compressed, asymmetric, and procumbent crown; I3 strongly reduced; C1 very small; (d)P1 small and simple; molar hypoconulid labial; coronoid retromolar fossa enlarged. As a proboscidean, Eritherium is then a member of wider clades Paenungulata, Afrotheria, and Atlantogenata. |
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phylogenetic reference(s)
Gheerbrant, E. 2009. Paleocene emergence of elephant relatives and the rapid radiation of African ungulates. Proceedings of the National Academy of Sciences, USA, 106:10717-10721.
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| tree image (click image for full size) | ||
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