Echinoidea

Brandon Richins, Jessica Stone, Caleb McDonald, Kaden Hardman

Members

Sea Urchins

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Sand Dollars

Physical and Behavioral Adaptations

• Their Ossicles overlap and are fused into a globular structure. It has a flattened or concave oral side, and it’s aboral species is arched in most species. They have spines and tube feet surrounding its body, which are used for movement and food gathering.
• If anything sharp touches them, they will immediately react and point all of their spines towards the point of impact. Seeing as they are sensitive to light, they are nocturnal, which allows them to move their spines in response to shadows.

Reproductive Strategies

• Members of Echinoidea reproduce in various ways and develop both direct and indirect
• Sperm and Egg can produce free swimming larvae
• Eggs may also be brooded by a female
• Free swimming larvae develop indirectly while brooded offspring develop directly

Class Characteristics & Body Structures

They do not have any arms.

They have a fivefold symmetry.

They have protected spines, it’s also a movable spine.

They have a rigid and spherical spine.

largest species can reach up to 36 cm

The mouth is at the base of the animal and the anus at the top

Habitat and Eating preferences

They are found in both Tide Pools and Deep ocean

They feed on algae, plankton, and other small organisms

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Sources

https://animaldiversity.org/accounts/Echinoidea/

http://www.seawater.no/fauna/echinodermata/Echinoidea.html

https://www.nhm.ac.uk/our-science/data/echinoid-directory/intro/reproduction.html

https://en.wikipedia.org/wiki/Sea_urchin

http://tolweb.org/treehouses/?treehouse_id=4881

https://en.wikipedia.org/wiki/Sea_urchin

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