Despite the long history of recognising the angiosperm order Apiales as a natural alliance, the circumscription of the order and the relationships among its constituent groups have been troublesome. Recent studies, however, have made great progress in understanding phylogenetic relationships in Apiales. Although much of this recent work has been based on molecular data, the results are congruent with other sources of data, including morphology and geography. A unified picture of relationships has now emerged regarding the delimitation of Apiales, which includes a core group of four families (Apiaceae, Araliaceae, Myodocarpaceae, Pittosporaceae) to which three small families are also added (Griseliniaceae, Torricelliaceae and Pennantiaceae). After a brief review of recent advances in each of the major groups, a revised classification of the order is presented, which includes the recognition of the new suborder Apiineae (comprising the four core families) and two new subfamilies within Apiaceae (Azorelloideae and Mackinlayoideae).
Plunkett, G. M., Chandler, G. T., Lowry, P. P., Pinney, S. M., & Sprenkle, T. S. (2004). Recent advances in understanding Apiales and a revised classification. In South African Journal of Botany (Vol. 70, pp. 371–381). NISC Pty Ltd. https://doi.org/10.1016/S0254-6299(15)30220-9