Finally , Argentinadraco does not have a downturned lower jaw , a step - like upper margin , or a deep crest , which all characterize tapejarines .
Jaw 's jaw is much less robust .
Finally , Argentinadraco does not have a downturned lower jaw , a step - like upper margin , or a deep crest , which all characterize tapejarines , and its jaw is much less robust .