👉 Ostracoidea is a taxonomic group of animals that includes creatures such as ostriches, ostracods (sea urchins), and other echinoderms. These animals are characterized by their long, pointed stumps or "osters" which they use for climbing and feeding on the surface of water. The term "ostra" is derived from the Greek word "ostros," meaning "stumps." The ostracoidea group includes a diverse array of creatures, including