Anatomy
M
Maxillary Bone
/ /mækˈsɪlərɪ/ /
Quick Definition
One of the bones forming the upper jaw of fishes; in advanced teleosts it functions to transmit force during jaw protrusion rather than bearing teeth.
📖 Full Definition
The maxilla (maxillary bone) is a paired bone forming part of the upper jaw. In primitive fishes (e.g. salmon, herring) the maxilla bears teeth and contributes to the gape. In advanced teleosts (perciforms, tetraodontiforms) the premaxilla has taken over the tooth-bearing role, and the maxilla has become a lever arm for jaw protrusion: as the premaxilla swings forward (protrudes) to engulf prey, the maxilla rotates and helps enlarge the gape. The shape and dentition of the maxilla are important taxonomic characters.