Within the class Demospongiae, we find in the order Poecilosclerida and the family Crambeidae the sponge Crambe crambe. It is a kind of encrusting sponge, so it does not form vertical structures, but colonizes horizontal surfaces such as rocks. They can cover considerable surfaces, there are specimens that exceed 1 square meter in area. The color of its tissue is orange red, and forms extensive flat plates of little thickness (from millimeters to centimeters thick) that are perforated by channels that are well visible.
We will find specimens of Crambe crambe throughout the Mediterranean Sea, as well as on the Portuguese and Spanish coasts of the Atlantic Ocean. Generally at depths of less than 25-30 meters and in places where it is protected from direct sunlight.
The feeding of Crambe crambe is by filtration of the water column that surrounds them. Through a multitude of small pores throughout its body, it inhales the surrounding water, and by means of specialized flagellated cells, creates the necessary current to generate the water current through its body, and thereby trapping small organic particles or bacteria from which it obtains the energy and compounds necessary for growth. All the water that has been filtered by the individual will be expelled through the osculum.
The reproduction of Crambe crambe occurs during the months of July and August. During this time, sperm are released into the sea and when they enter the cavity of another individual, fertilization of the eggs takes place. Once fertilization occurs, thousands of reddish larvae are released and will spend some time in free form as zooplankton to later settle to the substrate and form a specimen of Crambe crambe.
Crambe crambe can be confused with numerous other species, such as Crambe taillezi, Spurastrella cunctatrix or Hymniacidom sanguinea. The only way to identify it unequivocally is by studying under the microscope the siliceous spicules embedded in its tissue.Photos: