Related Clues:

• Take the bait?
• Lice, but down there
• Trawl
• Kvetches
• Easy mark, in cards
• Beach creatures
• Seek at random, with 'for'
• Crustaceans with stalked eyes
• Word to add to each theme answer that will make sense of its clue
• Aquatic creature
• Cranky folks
• Marlin or mackerel
• Beefs
• Sneakily probe (for)
• Aquatic fly?