A pharyngeal jaw and loose pharyngeal teeth from Prairie Creek, Indiana, and loose pharyngeal teeth and two basioccipital pharyngeal processes from Bell Cave, Alabama, appear to be those of
Moxostoma hubbsi (Copper Redhorse). Among suckers, only
M. carinatum,
M. hubbsi,
M.
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A pharyngeal jaw and loose pharyngeal teeth from Prairie Creek, Indiana, and loose pharyngeal teeth and two basioccipital pharyngeal processes from Bell Cave, Alabama, appear to be those of
Moxostoma hubbsi (Copper Redhorse). Among suckers, only
M. carinatum,
M. hubbsi,
M. robustum, and
M. ugidatli have molariform teeth on their pharyngeal jaws, with
M. hubbsi having the teeth of the largest relative size. Measurements of most of the teeth from Prairie Creek overlap with those of
M. hubbsi, and the largest tooth from Bell Cave is the largest pharyngeal tooth measured. The more complete pharyngeal process of the basioccipital possesses a small condyle and stout processes along it that are indicative of
M. hubbsi as well as a smaller centrum for articulation with the Weberian complex.
Moxostoma hubbsi currently occupies an area around Montreal, Canada, that was glaciated at the time the fossils were laid down, and the area was later occupied by the Champlain Sea and Lampsilis Lake before becoming riverine about 6000–5000 years ago, meaning that
M. hubbsi had to have arrived at its current distribution relatively recently and been extirpated from elsewhere.
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