black cod vs escolar

black cod

noun
  • Synonym of sablefish (Anoplopoma fimbria); (the sablefish is not a species of codfish; but is referred to as cod informally) 

escolar

noun
  • Any fish of species Ruvettus pretiosus, oilfish. 

  • Lepidocybium flavobrunneum, one of the snake mackerels. 

  • Any of several other perciform fish of the family Gempylidae (snake mackerels). 

How often have the words black cod and escolar occurred in a corpus of books? (source: Google Ngram Viewer )