In comparison, Paracryphiaceae were shown to share ten characters with Theaceae (but only six of them present in most members of the family), 13 characters with Actinidiaceae (seven of them present in most members), 11 characters with Ericaceae (seven of them present in most members), and 14 characters with Aquifoliaceae (seven of them present in most members).
Kobuski, who suggested that the taxon might be allied to Celastraceae or more likely to Theaceae.
They also commented on the advanced floral morphology of the genus, pointing out a number of features, such as stamens reduced to five in a single whorl and pendulous ovules reduced to two per locule, shared by Oncotheca and members of Theaceae subfamily Ter nstroemioideae.
More importantly, this study provided Dickison with additional proof, in the form of astrosclerids found in the leaves of the new species, that Oncothecaceae might be related to Theaceae.
Although the exact position of Oncothecaceae among angiosperms is still somewhat unclear, the family shows no affinity to Theaceae, Ebenaceae, Aquifoliaceae, or any other family suggested previously.