Clypeastroida
Quick Summary
The Clypeastroida are an order of marine invertebrates within the class Echinoidea, which is part of the phylum Echinodermata. These animals are commonly known as sand dollars. They are closely related to sea urchins and heart urchins.1
Sand dollars are characterized by their flat, disk-shaped bodies, which are well-adapted for burrowing in sandy environments. Their bodies are covered in small spines used for digging and crawling. The upper surface of a sand dollar displays a five-part radial symmetry, often appearing as a pattern of five "petals" radiating from the center. Most species measure between 2 to 4 inches (5 to 10 cm) in diameter and can be found in shallow coastal waters worldwide, with the exception of Europe and Antarctica.1
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- cake urchin
…marine invertebrates of the order Clypeastroida (phylum Echinodermata), in which the body is flattened. The surface is covered with short spines (often furlike) and inconspicuous pedicellariae (pincerlike organs). In many species the hollow, slightly elongated test (internal skeleton), which accommodates the water-vascular system, is symmetrically notched on the edge or…
Read More…marine invertebrates of the order Clypeastroida (phylum Echinodermata), in which the body is flattened. The surface is covered with short spines (often furlike) and inconspicuous pedicellariae (pincerlike organs). In many species the hollow, slightly elongated test (internal skeleton), which accommodates the water-vascular system, is symmetrically notched on the edge or…
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sand dollar…marine animals of the order Clypeastroida (class Echinoidea, phylum Echinodermata) that has a flat, disk-shaped body. They are close relatives of sea urchins and heart urchins. The sand dollar is particularly well adapted for burrowing in sandy substrates. Very small spines used for digging and crawling cover the entire surface…
Read More…marine animals of the order Clypeastroida (class Echinoidea, phylum Echinodermata) that has a flat, disk-shaped body. They are close relatives of sea urchins and heart urchins. The sand dollar is particularly well adapted for burrowing in sandy substrates. Very small spines used for digging and crawling cover the entire surface…
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