Ramellina

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Ramellina
Temporal range: Ediacaran
Scientific classification
Kingdom:
Phylum:
Genus:
RamellinaFedonkin, 1980
Species:
R. pennataFedonkin, 1980

Ramellina is a fossil from the Ediacaran discovered by Mikhail Fedonkin in 1980. The fossil has a leaf-like shape with short ridges, and lateral rollers.

Contents

Description

Ramellina has a leaf-like shape with shorter ridges extending on both sides of almost right angles, arranged alternating lateral rollers and width close to that of the axial roller. There are widened distal ends that have the length longest in the middle of the colony, and shortest at the ends, which gives the leaf shape to the colony. One end of the colony is pointed, and the other is rounded. There may be a growth zone in the colony suggested by secondary lateral processes. These lateral processes are thin and have a sharper angle between them, the axial lateral outgrowths are sharper than the middle of the colony. [1] Ramellina has been assigned to the phylum Cnidaria by J. Sepkoski. [2]

Diversity

Ramellinapennata, the only species in the genus, was discovered by M. Fedonkin in 1980 in Zimnii Bereg, White Sea, Russia. [3]

See also

Related Research Articles

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<i>Pomoria</i>

Pomoria corolliformis is an Ediacaran fossil that Mikhail Fedonkin described as resembling a modern-day sea anemone. The only known fossil specimen appears to have a long, gut-like tube that connects to its mouth and have circular protrusions that resemble modern cnidarian tentacles. 

References

  1. Fedonkin, M. A. (1980). "Fossil traces of Precambrian Metazoa". SSSR Series Geology. 1: 39–46.
  2. Sepkoski, J. J. (1992). "A compendium of fossil marine animal genera". Bulletins of American Paleontology. 363: 1–560.
  3. 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.