Ostracods are microscopic crustaceans, typically 0.2mm to 2mm long, with a bivalved calcareous shell. They first emerged around 500 million years ago and today inhabit every aquatic environment on earth.
Ostracods are found in a wide range of environments:
Their lifestyle ranges from free swimming to interstitial, where they rest among sediment. Ostracods can be:
Ordovician to present day. This group has living relatives.
Ostracods are minute but readily fossilised, and can occur in enormous numbers in some sediments.
Their fossils are widely distributed and are often found alongside foraminifera.
The Museum has enormous collections of ostracods, both fossil and non-fossil specimens. Learn more about the collections and search the fossil and recent ostracod database.