Microblog from Linda Bower MN
|Green Hydra - Wikimedia|
New to hydra? Here's an excerpt from an article by Northern State University of South Dakota, USA: "Hydra are named after the nine-headed sea snake of Greek mythology and are freshwater relatives of corals, sea anemones and jellyfish. All are members of a primitive phylum, the Cnidaria. The gut of cnidarians has only one opening. Unlike more complex animals, cnidarians are designed around 2 sheets of tissue: the ectoderm, lining the exterior; and the endoderm, lining the gastrovascular cavity. The two are separated by a gelatinous partition...greatly expanded in jellyfish, but is much reduced in hydra."
Chlorohydra viridissima is a bright green species, owing to the presence of numerous algae called zoochlorellae, which live as symbionts within the endodermal cells. Their relationship is mutualistic as the zoochlorellae carry out photosynthesis and produce sugars that are used by the hydra. In return, the carnivorous diet of the hydra provides a source of nitrogen for the algae.
|Hydra viridissima - Wikimedia|
|Hydra budding - Larry Wegmann|
You can read more in the Northern State University article.