Echinoderms Phylum Echinodermata, from the Greek for spiny skin

Phylum Echinodermata – spiney-skinned animals includes sea stars, brittle stars, sea urchins, sand dollars, sea cucumbers, and crinoids reverted back to radial symmetry tube feet and water vascular system

Echinoderms

Subphylum Asterozoa Classes –Asteroidea (sea star) – Ophiuroidea (brittle stars)

Subphylum Echinozoa Classes –Echinoidea (sea urchin and sand dollar) – Holothuroidea (sea cucumber)

Subphylum Crinozoa –Crinoidea (feather stars and sea-lillies)

Characteristics Adult echinoderms possess radial symmety

Sea star Class Asteroidea

Bat star

Brittle star Class Ophiuroidea

Sea urchin Class Echinoidea

Purple urchins

Sand-dollar Class Echinoidea

Sea cucumber Class Holothuroidea

Feather star Class Crinoidea

Characteristics Echinoderms' larvae are ciliated, free- swimming organisms that are bilaterally symmetrical

Characteristics echinoderms do not possess an external skeleton. a thin skin covers an endoskeleton made of tiny calcified plates and spines Echinoderms possess a unique water vascular system, a network of fluid-filled canals that function in gas exchange, feeding, and secondarily in locomotion echinoderms possess a complete digestive tube Many echinoderms can regenerate. Some sea stars are capable of regenerating lost arms. In some cases, lost arms have been observed to regenerate a second complete sea star. the seastar can insert its stomach through the opening of a bivalve and release gastric juices, digesting the prey alive during feeding

Echinoderm means spiny skin