E-Fauna BC: Electronic Atlas of the Wildlife of British Columbia

Ctenodiscus crispatus is a non-selective deposit feeder. Tube feet around the mouth shovel sediment into the stomach, which digests the organic material, much of it bacteria on the surface of sand grains. Fragments of bivalves, small crustaceans and worm tubes have been found in the stomachs of collected specimens. C. crispatus regularly extrudes indigestible material. It establishes a temporary burrow in soft sediment and uses its extensible epiproctal cone to maintain a connection with the water above. Currents created by ciliated grooves called cribriform organs draw sea water into the burrow for respiration. Any incidental food particles are trapped by a cleansing mucus and ingested. Cells lining these grooves have complex surfaces (microvilli) that can absorb amino acids directly from sea water. This type of nutrition may be important for surface cells that are not supplied by an internal blood system.

In the Gulf of Maine, there is no seasonal variation in gonad size, suggesting continuous reproduction. The full range of eggs can be found in the gonad at anyone time, but large mature eggs are most numerous in late autumn and mid winter in a Norwegian fiord. As with some other invertebrates, spawning seems to be related to phytoplankton production. The large, yolky egg implies direct development, but this is not known for certain. The Mud Star attains full size in three years. The species is extremely variable genetically.