 Much research, using both molecular data and fossils, has been conducted in recent years regarding the dating and distribution of the Acanthaceae and Lamiales lineage, although there still remains some ambiguity.In a 2004 study on the molecular phylogenetic dating of asterid flowering plants, researchers estimated 106 million years (MY) for the stem lineage of Lamiales, 67 MY for the stem lineage of Acanthaceae, and 54 MY for the crown node of Acanthaceae (that is, the age of extant lineages with the family).These estimates are older than those based on fossils that can confidently be assigned to Lamiales, which are middle Eocene in age, ca.