Ember serializer - Issues mapping type returned by server

Im using Ember 3.2 with JSON API end points. Im stuck on how to map data the server provides me to my models.

I have the following models:

// Model Zoo
export default DS.Model.extend({
    animals: hasMany('animal', {polymorphic: true})
})

// generic animal model
export default DS.Model.extend({
})

// animal-mamal model
export default DS.Model.extend({
  ...
})

// animal-reptile model
export default DS.Model.extend({
  ...
})

When consuming the resource example.com/zoo/:id/animal Im getting the following response:

{
  "data" : [ {
    "id" : ":some-id",
    "type" : "mamal-animals",
    "attributes" : {
      ...
    },
    "relationships" : {
      ...
    },
    "links" : {
      ...
    }
  }, {
    "id" : ":some-id",
    "type" : "reptile-animals",
    "attributes" : {
      ...
    },
    "relationships" : {
      ...
    },
    "links" : {
      ...
    }
  }]
}

Without implementing anything in the serializer I get the following in the console:

Encountered a resource object with type 
"mamal-animals", but no model was found for 
model name "mamal-animals" (resolved model name 
using '(unknown mixin).modelNameFromPayloadKey("mamal-animals")').

My models do not map with the type the server gives me. After getting that message, I wrote some code in the method modelNameFromPayloadKey from the Application serializer.

It basically maps the types the server provides me with to the models I have in the frontend.

// Map Backend type to Frontend models
const PAYLOAD_KEY_TO_MODEL = {
  'mamal-animals': 'animal-mamal',
  'reptile-animals': 'animal-reptile'
 }

export default DS.JSONAPISerializer.extend({
  // Map payload keys return by API to corresponding models in our app
  modelNameFromPayloadKey(key) {
    if(PAYLOAD_KEY_TO_MODEL[key]){
      return this._super(PAYLOAD_KEY_TO_MODEL[key]);
    } else {
      return this._super(...arguments);
    }
  }
})

Now it crashes with the following error:

Assertion Failed: You tried to push data with a 
type 'mamal-animals' but no model could be found with that name.

It seems it is still trying to find the type returned by the server instead of the model I provided.

I thought that the model name would be taken by implementing the modelNameFromPayloadKey method.

Any solution or ways to debug issues with serializer?