The "ivesheadiomorphs" are a group of fossilised structures known from

Ediacaran The Ediacaran Period ( ) is a geological period that spans 96 million years from the end of the Cryogenian Period 635 million years ago (Mya), to the beginning of the Cambrian Period 538.8 Mya. It marks the end of the Proterozoic Eon, and th ...

localities in

England England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe b ...

and

Newfoundland Newfoundland and Labrador (; french: Terre-Neuve-et-Labrador; frequently abbreviated as NL) is the easternmost province of Canada, in the country's Atlantic region. The province comprises the island of Newfoundland and the continental region ...

. They are considered to be taphomorphs, representing the poorly preserved biological remains of various contemporary

taxa In biology, a taxon (back-formation from ''taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular nam ...

such as ''

Charnia ''Charnia'' is a genus of frond-like lifeforms belonging to the Ediacaran biota with segmented, leaf-like ridges branching alternately to the right and left from a zig-zag medial suture (thus exhibiting glide reflection, or opposite isometry). T ...

'', ''

Charniodiscus ''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 ...

'', ''

Bradgatia ''Bradgatia linfordensis'' is a bush-like Ediacaran fossil. It consists of six or more fronds radiating from a central anchor point at the base. It superficially resembles a compressed cabbage in appearance, although in reality it had a more i ...

'', ''

Primocandelabrum ''Primocandelabrum'' is a genus of rangeomorph known from the Avalon-type Ediacaran biota. It makes up the brunt of some bedding plane assemblages. ''Primocandelabrum'' was described by Hofmann, O'Brien, and King in 2008. Diversity Fossil spe ...

'', ''

Pectinifrons ''Pectinifrons'' was a rangeomorph, a member of the Ediacara biota found at Mistaken Point, Newfoundland. It was a multi-branched organism with a comb-like appearance. It grew by adding fronds, then inflating them. See also * List of Ediacaran ...

'' and others, that were effaced by partial decay by micro-organisms following death on the seafloor before burial by sediment. Ivesheadiomorph structures were previously described as distinct organisms, namely ''Ivesheadia lobata'' ("pizza disk"), ''Blackbrookia oaksi'', ''Shepshedia palmata'' and ''Pseudovendia charnwoodensis''. However, all of these fossils have since been rejected as valid taxa.

References

Ediacaran life Ediacaran Canada Ediacaran Europe {{Ediacaran-stub