English translation:
called, named, as much as
Structure
Noun + という + Noun
Why is Noun + だ + という + Noun not used in this format?
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Hey and welcome on the community forums! 
Think of it as a convention, this way it is easier to distinguish it from other uses of という, like for example when it is used at the end of a sentence to express hearsay, where だ can precede it. (彼はアメリカ人だという I heard that he is an American)
So, when you see ワンダという魚 you know it means a fish called wanda.
I hope it helps cheers!
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So it’ll accept という and っていう but shouldn’t just って also be accepted?
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って on its own is understood as a は, as they serve the same basic function of topic marker particles. Only difference is that って is much more casual.
When used as っていう、it’s a direct replacement of と。That’s why って only isn’t accepted. Hope this cleared it up!