Echinoderms and Arthropods

Echinoderms (spiny skinned) starfish, urchins, sea cucumbers and sand dollars

-Radially symmetrical called Pentamerous radial symmetry -no head, no dorsal or ventral side

-complete digestive tract - endoskeleton

-can have spines or bumps -Water Vascular system -tube feet for movement

-Madreporite, small dot that connects vascular system

Sea Stars Asteroides

Mouth - anus

Aboral and oral

Brittle Stars Ophiuroidea

Very long and flexible arms

Quick movements

No anus

Sea Urchins Echinoidea

Round skeleton (Test)

moveable spines tube feet for movement

Aristotle’s Lantern

Sea Cucumbers Holothuroidea

Like big slugs Don’t move much but

move by tube feet Mouth - anus Evisceration

Arthropods Crustaceans

Barnacles, copepods, isopods, krill Shrimp, Lobsters and Crabs

krill

tongue biter

Barnaclesbarnacles matingbarnacle penis's

feeding

Shrimp

pistol shrimp

cleaner shrimp

hermit crabhorseshoe crab mating

christmas island red crabcrab fishing

Crabs

Lobster

moltinglobster colorsJohnathan Byrd. My WORLD