Vendian Fossils Death Assemblage
Cyclomedusa davidi and Hiemalora stellaris


Cyclomedusa davidi & Hiemalora stellaris

Geological Time: Precambrian, Vendian (600 - 550 Million Years Old)

Size: Cyclomedusa 40 mm X 37 mm; Hiemalora 40 mm X 30 mm

Fossil Site: White Sea Summer Coast, Archangelsk, Russia


Cyclomedusa and HiemaloraDescription: This spectacular death assemblage predates the Cambrian Explosion by tens of millions of years. Many early attempts at diversity were present during this time, both here and in the Ediacara Fauna of the Flinders CyclomedusaRanges of Australia. Many strange forms were present, some of which still do not have any parallels in modern times. These jellyfish-like examples are one that is relatively easy to attribute to descendants alive today. The incredible soft-bodied preservation is believed to be the result of impressions Hiemaloramade in a microbial mat contained within the sand. There is debate about the true nature of both these examples. Cyclomedusa was initially thought to be a pelagic jellyfish, but is now more likely a benthic organism much like a sea anemone.

The one below it was thought to possibly be a member of the Cnidaria by virtue of its tentacle-like structures. Given that Cyclomedsa is not found with preserved tentacles, Hiemalora is now thought to be the anchor of some larger, as yet unknown creature.

click fossil pictures to enlarge

Cyclomedusa davidi & Hiemalora stellaris
Cyclomedusa davidi
Cyclomedusa davidi and Hiemalora stellaris
Cyclomedusa davidi and Hiemalora stellaris
Cyclomedusa davidi
Hiemalora stellaris
Hiemalora stellaris

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