Modifiers matching gastropod:

• marine,
• terrestrial,
• intertidal,
• common,
• large,
• smaller,
• small,
• herbivorous,

Simple categories matching intertidal:

• fauna,
• mollusk,
• invertebrate,
• organism,
• species,
• creature,
• herbivore,
• mollusc,
• snail,
• animal,
• structure,
• gastropod,
• bivalve,
• arthropod,
• prey,
• shellfish,
• system,