Ramellina
| Ramellina | |
|---|---|
| Scientific classification | |
| Kingdom: | |
| Phylum: | |
| Class: | |
| Genus: | †Ramellina Fedonkin, 1980
|
| Species: | †R. pennata
|
| Binomial name | |
| †Ramellina pennata Fedonkin, 1980
| |
Ramellina is a fossil from the Ediacaran of the Ust' Pinega Formation of Russia. The fossil has a leaf-like shape with short ridges, and lateral rollers. It is a monotypic genus, containing only Ramellina pennata.
Discovery
Ramellina was discovered in the uppermost part of the Verkhovka Subformation, Ustʹ Pinega Formation, on the Winter Coast (Zimnii Bereg) of the White Sea, Northwestern Russia, and described in 1980.[2][3] It was found several meters below a volcanic ash bed with a U-Pb date of 552.96 ± 0.19 Ma.[1]
Etymology
The generic name Ramellina derives from the Latin word ramulus, to mean "little branch". The specific name pennata also derives from the Latin word pennatus, to mean "feathery".[2]
Description
Ramellina is a leaf shaped organism, and is between 20–35 mm (0.8–1.4 in) in length. The shape is due to the secondary polyps on either side of the midline are at their shortest length at the ends of the body, and are at their full length in the middle which is up to 4.5–6 mm (0.2–0.2 in), and number about 20. One end is smoothly rounded whilst the other end is pointed, where the polyps are notably thinner, which may show the growth region of Ramellina.[2]
Affinities
Originally described by M. Fedonkin in 1980 as a feather-like colony of polyps with unclear systematic affinity, similar to some colonial members of Hydrozoa and Anthozoa, Ramellina was later included by him in 1985 into the phylum Petalonamae, which unites Ediacaran frondose organisms.[2][4]
See also
References
- ^ a b Yang, Chuan; Rooney, Alan D.; Condon, Daniel J.; Li, Xian-Hua; Grazhdankin, Dmitriy V.; Bowyer, Fred T.; Hu, Chunlin; Macdonald, Francis A.; Zhu, Maoyan (5 November 2021). "The tempo of Ediacaran evolution". Science Advances. 7 (45). doi:10.1126/sciadv.abi9643. PMC 8565906.
- ^ a b c d Fedonkin, M. A. (1980). "Fossil traces of Precambrian Metazoa". SSSR Series Geology. 1: 39–46.
- ^ Fedonkin, M. A. (2007). The rise of animals: evolution and diversification of the kingdom animalia. Baltimore, Md.: Johns Hopkins University Press. ISBN 9780801886799. OCLC 85162342.
- ^ M. A. Fedonkin (1985). "Systematic Description of Vendian Metazoa". Vendian System: Historical–Geological and Paleontological Foundation. 1: Paleontology. Moscow: Nauka: 70–106.