They are all animals that do not have a backbone.
Mollusks like clams and octopi They have a shell or a mantel.
Arthropods like spiders and crabs They have an exoskeleton, segmented bodies & jointed appendages.
Butterfly Life Cycle Coloring Page
Annelids & Platyhelminthes like worms They are segmented with soft, bilaterrally symmetrical bodies.
Echinoderms like starfish They have a five part radial symmetry, internal skeleton and water vascular systems.