Comparative osteological studies of the sturgeon genus Acipenser are rare. In this paper, the rostral canal bones of Acipenser brevirostrum and Acipenser oxyrinchus oxyrinchus are compared and three new osteological features that distinguish these species are described. In lateral view, the jugal bone of adult A. o. oxyrinchus possesses distinct vertical and horizontal arms, whereas that of A. brevirostrum is roughly triangular in shape. The posterior rostral canal bones in A. o. oxyrinchus possess larger and more pointed medial expansions relative to those found in A. brevirostrum. The rostral canal bones immediately lateral to the commissure in adult A. o. oxyrinchus are ornamented with thorn-shaped processes, which differ from the simple Y-shaped tubes found in A. brevirostrum and other taxa examined.