Oral fissure
Rima oris
Definition
The oral fissure is the part of the mouth that communicates with the outside. It is delimited by the upper and lower lips.
Elongated in proportion to the face, the oral slit is much longer than it is wide in ungulates, and especially in equids. By contrast, it is particularly short in cats and in humans.
References
Barone R. Anatomie comparée des mammifères domestiques, Tome 3, Splanchnologie I, 4th edition, Vigot, Paris, 2017.
