Petalonamae

Charniodiscus is an Ediacaran fossil that in life was probably a stationary filter feeder that lived anchored to a sandy sea bed. The organism had a holdfast, stalk and frond. The holdfast was bulbous shaped, and the stalk was flexible. The frond was segmented and had a pointed tip. There were two growth forms: one with a short stem and a wide frond, and another with a long stalk, elevating a smaller frond about above the holdfast. While the organism superficially resembles the sea pens (cnidaria), it is probably not a crown-group animal.

The rangeomorphs are a group of Ediacaran fossils. Ediacarans are the oldest large fossil organisms on earth, and many are not self-evidently related to anything else that has ever lived. However, some Ediacarans clearly resemble each other. Paleontologists have not been able to agree on what else, if anything, is related to these organisms, so Ediacarans are usually classified into groups based on their appearance. These "form taxa" allow scientists to study and discuss Ediacarans when they cannot know what kind of living things they were, or how they were genetically related to each other. R

The petalonamids (Petalonamae) or frondomorphs are an extinct group of archaic animals typical of the Ediacaran biota, dating from approximately 635 million years ago to 516 million years ago. They are benthic and immobile animals,

Stromatoveris psygmoglena is a genus of fossil organism from the Chengjiang deposits of Yunnan that was originally aligned with the fossil Charnia (strictly, the Charniomorpha) from the Ediacara biota. However, such an affinity was thought to be developmentally implausible and so S. psygmoglena was thought to be either a sessile basal ctenophore, or a sessile organism closely related to ctenophores instead. Nevertheless, a 2018 phylogenetic analysis by Jennifer Hoyal Cuthill and Jian Han indicated that Stromatoveris was a member of Animalia and closely related to ediacaran frond-like lifeforms