-
Arkarua adami is a small,
Precambrian disk-like
fossil with a
raised center, a
number of
radial ridges on the rim, and a five-pointed
central depression...
-
preserved to
analyze its characteristics. One much
earlier form
called Arkarua has been
hypothesized to be an
ancestral echinoderm because of its fivefold...
- may not
extend into the
Precambrian (provided the
enigmatic Ediacaran Arkarua can be
positively identified as an edrioasteroid). The
classes currently...
-
purpuratus Crinoid on a
coral reef The
oldest candidate echinoderm fossil is
Arkarua from the
Precambrian of Australia.
These fossils are disc-like, with radial...
- More than 100
genera have been described, and well
known forms include Arkarua, Charnia, ****insonia, Ediacaria, Marywadea, Cephalonega, Pteridinium,...
- Some
authors propose that an
enigmatic Ediacaran (about 600 Ma)
organism Arkarua is also an edrioasteroid, but this
interpretation did not gain wide acceptance...
- however, have been
interpreted as
early molluscs (Kimberella),
echinoderms (
Arkarua), and
arthropods (Spriggina, Parvancorina).
There is
still debate about...
- needed]
having been
interpreted as
early molluscs (Kimberella),
echinoderms (
Arkarua); and
arthropods (Spriggina, Parvancorina, Yilingia). Still,
debate exists...
-
earliest known, more or less
undisputed edrioasteroid. The
pentamerous Arkarua is older,
dating from the late Precambrian, but with
existing fossils of...
- however, have been
interpreted as
early molluscs (Kimberella),
echinoderms (
Arkarua), and
arthropods (Spriggina, Parvancorina).
There is
still debate about...
