Why was the family Peraceae recognized separately from Euphorbiaceae?

The family Peraceae was recognized as a separate entity from Euphorbiaceae due to findings from intensive molecular studies.1

These studies revealed that the previously unplaced family Rafflesiaceae—a group of parasitic plants—is closely related to the core Euphorbiaceae. Because Peraceae was identified as the sister group to the combined clade of Rafflesiaceae and Euphorbiaceae, it was formally recognized as a distinct family to accurately reflect these evolutionary relationships. This taxonomic shift is part of a broader trend in which molecular evidence has led to the splitting of the traditional, more broadly defined Euphorbiaceae into several different families.1