Answer:
Shrimp
Step-by-step explanation:
The shrimp only eat diatoms and dinoflagellates who get their energy from the sun, making them producers
Shrimp are still considered primary consumers even though they eat phytoplankton, which are a producer rather than a plant. This is because phytoplankton gets energy from the sun, not plants. You can read more in producers but this is primary consumers.