Common Name[]
Spine tube
Scientific Name[]
Pyrrhotubus cornuta
Description[]
This photobiont has a shape similar to that of Earth's sponges. The inside of sponges are lined with cells with flagella that whirl water through the cavity and filter out bacteria and plankton - but the tissue on the inside is - at least superficially - identical to the tissue on the outside. I suppose my dreams of a sessile consumer of wayward midge-like organisms are crushed - but it doesn't explain the cup-shape. Does rainwater collect there? Is it a specialized microenvironment that aids reproduction or growth? What purpose does that pale stalk serve? --Jane Van Susteren, Exobiology Lead