Ediacara biota
The organism bears a very superficial resemblance to echinoderms, ctenophores and to some of the other Ediacara biota, but it lacks sufficient physical characteristics to ascertain with any degree of certainty whether it is indeed an animal or not. If it is, it would be the earliest known fossil of an adult animal; and its anatomy is consistent with that expected from the earliest animals. However, it is not perfectly clear that it is an animal; algae, the dominant constituent of the Doushantuo biota, cannot be ruled out, except that "Eoandromeda" seems a little too complex.