Northern Sea Urchins (Strongylocentrotus nudus), Green Sea Urchins (Hemicentrotus pulcherrimus), Itomaki Starfish (Asterina pectinifera), Japanese Sea Cucumber (Apostichopus japonicus), and Plumose Anemone (Metridium senile). The signage is all in Japanese without scientific names, so I don't what the mussels are.