Yes, they are a species of cod.
There are several/many species of fish that are called "Cod". They all have scales as far as I know.
they have fins but no scales, only skin.
Cod, ling and hake.
Black codfish do have scales, which are generally very small. Possibly due to the size and color of the scales, it may seem that the black cod does not have scales.
Cod was a generic name for various kinds of fish (including hake and the haddock) and can refer to different fish in different parts of the world. In those parts of the world where cod refers to fish with scales, then cod will be Kosher. All Kosher fish need fins and scales.
Its a saltwater fish, that looks a bit like a cod.
Yes they do. They are in the cod family.
Yes, cod have scales. They have cycloid scales which have a smooth outer edge, making them more difficult to spot.
There are several species of kosher cod and several species of non-kosher cod, so the status of Blue Ling is not immediately clear. Most commercial cod species are in the Gadidae family and several are kosher, such as cod, haddock, pollock, and whiting. Non-kosher cods are also in the Gadidae family and include the Burbot and the Lawyer, also called Freshwater Ling (Lota Lota). However, Blue Ling is in the less familiar Lotidae family. There are detailed lists online of kosher and non-kosher fish, and Blue Ling is not listed.
No, it is not, a cod fish is a type of fish.