The diagram on the left shows the lifecycle of Pasteuria ramosa, a bacterial parasite of Daphnia. Susceptible hosts acquire the infection from spores in the sediment or in suspension. The parasite develops mainly in the host's body cavity and muscle tissue, increasing in density and eventually expanding to occupy the entire host. Typical effects on the host are sterility and gigantism. Spores are released mainly after the host dies and sinks to the substrate, and sometimes directly to the water via clumsy predation.
