Sublabial scale
In reptiles, the sublabial scales, also called lower-labials or infralabials, are those scales that border the mouth opening along the lower jaw. They do not include the median scale[1] (mental scale). The term labial originates from labium (Latin for "lip"), which refers to any lip-like structure. The numbers of these scales present, and sometimes the shapes and sizes, are some of many characteristics used to differentiate species from one another.