Tectitethya crypta

Tectitethya crypta is a demosponge found in the Caribbean Sea, particularly in the Florida Keys, Dry Tortugas, and north-west shores of Cuba. It thrives in shallow waters, typically between 1 to 20 meters deep, on soft substrates like sand and mud. Its appearance is often obscured by a coating of sand and algae, giving it a cream or gray color, though its actual pigment is green and gray. The sponge is characterized by its amorphous, bulky body, which can be cylindrical, conical, or hemispherical, and is about the size of a fist. The surface is dotted with flat tubercules and covered in sediment, which plays a role in its structural stability. T. crypta is a filter feeder, drawing in nutrients through its ostia and expelling water through the osculum. Its diet includes various microorganisms such as Chaetoceros and pinnulaira. The sponge reproduces both sexually, with parenchymella larvae, and asexually through budding. Its ability to contract its body and close its osculum is an adaptation to its sandy environment, aiding in nutrient circulation and providing a habitat for other organisms. Divers encountering T. crypta may find it partially buried in sand, with larger sponges often attached to the substrate and smaller ones resting freely. While not evaluated by the IUCN, this species has contributed to medical advancements through the discovery of compounds that led to antiviral and cancer treatment drugs.