Polemidia

Polemidia

Geological time
Miocene
Age
13.6–11.6 million years ago
Period
Middle Miocene
Formation
Pakhna Formation
Depositional environment
Deeper offshore marine shelf
Fossil types
Planktonic pteropods (Diacria trispinosa), small bivalves
Paleoecology highlights
Quiet, open water with slow-settling carbonate mud; drifting plankton; occasional fine bioclastic rain from distant shallows

Imagine standing on the seafloor over 13 million years ago, far offshore beneath a calm, subtropical sea. Light from above filters down in soft blue-grey tones, just enough to faintly illuminate the pale, fine-grained seabed beneath your feet. The ground is smooth and powdery, made of soft chalky mud slowly settling from the clear water above. There are no corals, no plants, and no bustling marine life here; just the quiet drift of tiny plankton shells from far above, sinking gently and undisturbed. It’s a still, peaceful world; dim, silent, and seemingly endless in all directions.

Polemidia shown on the globe Map
Artistic depiction of Autobranchia

Autobranchia

1 specimen
Artistic depiction of Plantae

Plantae

1 specimen
Artistic depiction of Unclassified

Unclassified

1 specimen