Oct 1, 2018 · Information about the Class Echinoidea, including classification, feeding, habitat, reproduction and human uses.

Sea urchins or urchins (/ ˈ ɜːr tʃ ɪ n z /) are typically spiny, globular animals, echinoderms in the class Echinoidea. About 950 species live on the seabed, inhabiting all oceans and depth zones from the intertidal to 5,000 metres (16,000 ft; 2,700 fathoms). [1]

May 27, 2020 · Echinoids are the sister taxa to holothuroidians within the Echinozoa clade. Like other extant echinoderms, species in this mobile class primarily exhibit pentaradial symmetry—some have evolved bilateral symmetry—and use a water vascular system for movement and food capture.

Echi­noids graze on just about any­thing they come across, plant or an­i­mal. This in­cludes algae, bry­ozoans, and dead an­i­mals. Mem­bers of this class are food for crabs, sea stars, fish, birds, ot­ters, and other mam­mals.

Sea urchins are spiny, globular echinoderms in the class Echinoidea. About 950 species of sea urchin are distributed on the seabeds of every ocean and inhabit every depth zone from the intertidal seashore down to 5,000 meters (16,000 ft; 2,700 fathoms).

Confused by a class within a class or an order within an order? Please see our brief essay.

Aug 24, 2022 · Echinoidea is the class of Echinoderms that includes sea urchins, sand dollars, sea biscuits and others. The spines observed on these organisms are actually mobile, which serves to enhance protection, feeding, and aid in movement. Echinoidea are encased in an endoskeleton commonly called a test.

Sea urchins, are typically spiny, globular animals, echinoderms in the class Echinoidea. About 950 species live on the seabed, inhabiting all oceans and depth zones from the intertidal to 5,000 metres (16,000 ft; 2,700 fathoms).

Sea urchins and sand dollars are classified within a broader group called the Echinoidea. Broadly speaking all echinoids have an endoskeleton composed of distinct fused plates which often form distinctive patterns.

Echinoids graze on just about anything they come across, plant or animal. This includes algae, bryozoans, and dead animals. Members of this class are food for crabs, sea stars, fish, birds, otters, and other mammals. Probably the single most important contribution of these animals to scientific knowledge is their embryological development.