Leviticus 11:8-12

You shall not eat any of their flesh nor touch their carcasses; they are unclean to you.

‘These you may eat, of whatever is in the water: everything that has fins and scales, in the water, in the seas, or in the rivers, you may eat.

But whatever is in the seas and in the rivers that does not have fins and scales among all the teeming life of the water, and among all the living creatures that are in the water, they are detestable things to you,

and they shall be detestable to you; you may not eat any of their flesh, and you shall detest their carcasses.

Whatever in the water does not have fins and scales is detestable to you. Avoid the Unclean