Zera is based on a Torosaurus, which is distinguished from the contemporary Triceratops by an elongate frill with large openings, long squamosal bones of the frill with a trough on their upper surface, and the presence of five or more pairs of horns on the back of the frill.
A study of fossil bone histology combined with an investigation of frill shape presumed that Torosaurus probably represented the mature form of Triceratops. In 2011 through 2013 however, studies of external features of known specimens have claimed that morphological differences between the two genera preclude their synonymy. The main problems are a lack of good transitional forms, the apparent existence of authentic Torosaurus subadults, different skull proportions independent of maturation and the assertion that hole formation at an adult stage is not part of a normal ceratopsian maturation sequence.
Zera is the first female Triceraton to ever appear in the franchise.
Another female Triceraton was meant to appear in Tale of the TMNT, vol 2 long before Zera came in, but the idea was put aside. Coincidentally, her name was Zura, with an "U" instead of an "E".