Crayfish and worm: doomed old friends?
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Crayfish and worm: doomed old friends?

Bizarre, tentacled worms and the crayfish that they spend their lives attached to are both in danger of extinction, a study has found.

Based on analysis of the DNA of several species of both worms and fish, researchers concluded that the two types of animal have coexisted in the rivers of Australia for nearly 80 million years.

This video shows some of the worms - known as temnocephalans - adorning the shell of a spiny mountain crayfish from Sydney.

Footage: David Blair, James Cook University