The Axolotl (​Ambystoma mexicanum)​ ​can be induced with thyroxine hormone to undergo metamorphosis, resulting in physiological and anatomical changes that enable terrestrialization. As the Axolotl’s feeding morphology changes, feeding kinematics are also expected to change, but past research has been mostly limited to studying external feeding kinematics. We sought to determine if contraction of sternohyoid (SH), one of the main muscles involved in feeding, and an important linkage between the feeding apparatus and the body musculature, changes across terrestrialization. Shortening of SH expands the buccal cavity in animals by lowering and retracting the hyoid, and can also aid in gape opening, whereas shortening of the hypaxial musculature may lengthen SH. We hypothesized that SH would undergo active lengthening in water during strikes, a gape-expansive behavior, due to the drag imposed on skull expansion by the dense fluid medium. Therefore, SH length-changes during strike were expected to be greater during gape opening than closing, in both aquatic and terrestrial Axolotls. We implanted SH with radio-opaque markers and recorded 3D videofluoroscopy data of feeding before and after terrestrialization. Peak SH lengthening occurred as the mouth was opened in both aquatic and terrestrial axolotls. Peak shortening of sternohyoid occurred during gape closing as the tongue was being retracted. The difference between mean SH shortening in terrestrial versus aquatic feeding was only 2%, compared to a 35% difference in lengthening. These results support our hypothesis of SH contraction changing with terrestrialization, and broaden our understanding of the challenges associated with terrestrialization and the evolution of feeding systems.