We place this new form in the Tetraodontiformes because it
has a reduced number of caudal-fin rays (12), a reduced number
of vertebrae (probably 18-20), and because it lacks anal-fin spines. We place it in the Balistoidea (sensu Winterbottom,
1974: the balistids, including monacanthids; the ostraciids,
including aracanids; and the Eocene spinacanthids) because it
has a reduced number (3) of dorsal-fin spines, a reduced pelvic
fin (a rudimentary spine at the end of the pelvis), a reduced
number of teeth, which are of heavy conical shape, and
enlarged scale plates forming a partial carapace with spiny
processes. In several ways the new form is anatomically
intermediate between the ostraciid trunkfishes and the clade
composed of the balistid triggerfishes and their Eocene
spinacanthid sister group. We place the new form incertae sedis
in an unresolved trichotomy with the balistids and spinacanthids.
This is reflected in the following hierarchical synopsis.