Rangeomorph

Rangeomorph Temporal range: 635–505 Ma PreꞒ Ꞓ O S D C P T J K Pg N Possibly one of the last representatives of the Ediacaran biota.
Charnia masoni, a rangeomorph
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	†Petalonamae
Clade:	†Rangeomorpha Hofmann et al., 2008
Subtaxa
†Avalofractus †Broccoliforma †Fractofusus †Frondophyllas †Hapsidophyllas †Hylaecullulus †Khatyspytia †Pambikalbae †Pectinifrons †Plumeropriscum †Primocandelabrum †Trepassia †Vinlandia †Rangeidae †Rangea †Charniidae †Beothukis †Bomakellia †Bradgatia †Charnia †Paracharnia †Culmofrons
Synonyms
Charniomorpha

The rangeomorphs are a group of Ediacaran fossils. Ediacarans are the oldest large fossil organisms on earth, and many are not obviously related to anything else that has ever lived. However, some Ediacarans clearly resemble each other. Palentologists 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. Rangeomorphs look roughly like fern fronds or feathers arranged around a central axis; the group is defined as Edicarans with a similar appearance and structure to the genus Rangea. Some researchers, such as Pflug and Narbonne, believe all rangeomorphs were more closely related to each other than to anything else. If true, this would make the group a natural taxon called Rangeomorpha (just as all insects are more closely related to each other than to any non-insects, and therefore are a natural taxon called Insecta).

Rangeomorphs are a key part of the Ediacaran biota, which survived about 30 million years, until the base of the Cambrian, 538.8 million years ago. They were especially abundant in the cold, deep-ocean environments of the early Ediacaran, as shown in the Mistaken Point assemblage in Newfoundland.^[1]