Tadpole Shrimp
CopyrightStone Museum of Geology
Triops, also known as tadpole shrimps, are a group of arthropod crustaceans found in temporary standing pools of fresh or brackish water. Dating back 300 milion years to the Carboniferous Period, 15 species of Triops can today be found on every continent except Antarctica.

The specimen in the photograph is of the American genus, Triops longicaudatus, that grows up to around 2" long and lives for about eight weeks.

Sharing many similar physical characteristics with both the living Horseshoe Crab and extinct Trilobites, these animals can grow up to 11cm (over 4"). Around the UK, they are most likely to be found off the west coast of Scotland in waters warmed by the Gulf Stream.

Triops - when isolated from others of their kind - can reproduce parthenogenetically (without sex or a mate) and lay their eggs in sand. These lay dormant until at least one cycle of drying out/rehydration occurs.

Like all arthropods, Triops grow by shedding their outer skin and growing a new one underneath. A healthy Triops with an adequate food supply and optimum conditions of water quality, temperature and light will do this once or twice each week.
CopyrightStone Museum of Geology