Scyphozoans
Scyphozoans, known today as Jellyfish, are made of a jelly-like material so they are preserved only as 'Trace Fossils'.
It is extremely rare to find one and they are hard to recognise as sometimes all that is preserved is a circular dent in the rock.
Identifying them is easier than finding them.
The dates are not all complete as they are rarely preserved and those that are found in one layer are the same age.
The earlier Scyphozoans are only found preserved flat on the sea floor; this suggests they couldn't swim freely.
Cunina
UPPER PRE-CAMBRIAN TO UPPER TERTIARY. 550-0 MYA.
Cunina is recognised by it's unique Tentacle arrangement.
2 cm is a decent size for a Cunina.
It has a Tentacle for every segment of it's Bill.
It's hood is a perfect semi-circle.
2 cm is a decent size for a Cunina.
It has a Tentacle for every segment of it's Bill.
It's hood is a perfect semi-circle.
Ediacaran Medusoid
UPPER PRE-CAMBRIAN. 570 MYA.
Ediacaran Medusoid is recognised by it's unique radiating shape.
10 cm is a decent size for an Ediacaran Medusoid.
Ediacaran Medusoids were discovered in a mud slide in Australia.
As it is preserved flat on the sea floor, it takes the shape of it's bill.
It is normally smaller than a Mawsonite.
10 cm is a decent size for an Ediacaran Medusoid.
Ediacaran Medusoids were discovered in a mud slide in Australia.
As it is preserved flat on the sea floor, it takes the shape of it's bill.
It is normally smaller than a Mawsonite.
Essexella
UPPER PENNSYLVANIAN. 300 MYA.
Essexella is recognised by it's unique hood-like Tentacles.
10 cm is a decent size for an Essexella.
Essexella is not preserved on the sea floor, which suggests it swam freely.
Its only identifiable feature is its hood-like shape. Even if this is not visible, if it is found in the Pennsylvanian, it is likely that it is Essexella.
10 cm is a decent size for an Essexella.
Essexella is not preserved on the sea floor, which suggests it swam freely.
Its only identifiable feature is its hood-like shape. Even if this is not visible, if it is found in the Pennsylvanian, it is likely that it is Essexella.
Mawsonite
UPPER PRE-CAMBRIAN TO MIDDLE SILUARIAN.
570-420 MYA.
Mawsonite is recognised by it's unique radiating shape.
15 cm is a decent size for a Mawsonite.
Unlike modern Jellyfish the Mawsonites were preserved on the sea floor, so it was thought it didn't swim freely,
we now know they did swim freely.
Mawsonites were discovered in a mud slide in Australia (The one shown is not Australian). As it is preserved flat on the sea floor it takes the shape of it's Bill.
15 cm is a decent size for a Mawsonite.
Unlike modern Jellyfish the Mawsonites were preserved on the sea floor, so it was thought it didn't swim freely,
we now know they did swim freely.
Mawsonites were discovered in a mud slide in Australia (The one shown is not Australian). As it is preserved flat on the sea floor it takes the shape of it's Bill.
Phylum Cnidaria
UPPER CAMBRIAN TO UPPER TERTIARY. 510-0 MYA.
Phylum Cnidaria is recognised by it's unique shape, ring-on-ring effect.
30 cm is a decent size for a Phylum Cnidaria.
It's Tentacles are only visible if it is preserved on it's side.
When it is preserved flat on the sea floor, it is a circular shape with a ring-on-ring effect.
When it is preserved on it's side, it looks like a semi-circle attached to
some Tentacles (Tentacles show up as shadows in the rock).
30 cm is a decent size for a Phylum Cnidaria.
It's Tentacles are only visible if it is preserved on it's side.
When it is preserved flat on the sea floor, it is a circular shape with a ring-on-ring effect.
When it is preserved on it's side, it looks like a semi-circle attached to
some Tentacles (Tentacles show up as shadows in the rock).
