Simplify the following text for a Grade 11 native English-speaking person.
Original: Shellfish is a culinary and fisheries term for exoskeleton-bearing aquatic invertebrates used as food , including various species of molluscs , crustaceans , and echinoderms .
Simplified: Shellfish is a culinary term for aquatic invertebrates used as food : molluscs , crustaceans , and echinoderms .