Deuteronomy 14:10
But any which have no skin-plates or wings for swimming, you may not take; they are unclean for you.
Treasury of Scripture Knowledge
Summary
And whatsoever hath not fins and scales ye may not eat; it is unclean unto you.
General references
Bible References
General references
Leviticus 11:9
These you may have for food of all things living in the water: anything living in the water, in the seas or rivers, which has special parts for swimming and skin formed of thin plates, may be used for food.