Theneidae

Theneidae is a family of demosponges within the order Tetractinellida. Sponges belonging to this family are characterized by their generally massive or encrusting growth forms and their siliceous skeletons composed of tetractine megascleres (specifically calthrops and derivatives) and microscleres such as sigmas and microxeas. Theneidae sponges are found in marine environments, often in deeper waters, though some species occur in shallower regions. They are filter feeders, drawing water through their bodies to extract organic particles. The taxonomy of Theneidae and related sponge families is continually being refined based on morphological and molecular data.