Are there any marine animals that are forbidden to eat?

Allah Almighty has permitted aquatic foods, whether animal or plant, alive or dead, based on His saying: "Lawful to you is the pursuit of the sea and its food as provision for you and for travelers." However, some scholars have made the following exceptions:

1. Crocodile: The majority of scholars do not permit eating it because it has fangs and lives on land, whereas the Malikis consider it permissible based on its inclusion in the general meaning of the verse. 2. Frog: It is not permissible to eat it because the Prophet, peace and blessings be upon him, forbade killing it. 3. Sea snake: The correct view is that it is permissible to eat it if it lives exclusively in the sea, due to the generality of the verse. 4. Sea dog (seal) and turtle: The correct view is that it is permissible to eat them after ritual slaughter (dhabaḥ) because they live both on land and in the sea. Anything that lives both on land and in the sea takes the rulings of land animals, thus requiring ritual slaughter, except for crab, which does not require ritual slaughter because it does not have blood. 5. Anything that causes harm: It is not permissible to eat anything that causes harm, even if it is aquatic, based on the Almighty’s saying: "And do not kill yourselves. Indeed, Allah is to you Merciful" and "And do not throw [yourselves] with your [own] hands into destruction."