Elephantimorpha is a clade of proboscideans that contains the Mammutidae (mastodons), as well as Elephantida (amebelodonts, choerolophodonts, gomphotheres, stegodontids and elephantids). All members of this group have the horizontal tooth replacement typical of modern elephants, unlike more primitive members of the Elephantiformes.[1] Like modern elephants, the ancestor of Elephantimorpha was likely capable of communicating via infrasonic calls. While early elephantimorphs generally had lower jaws with an elongated mandibular symphysis at the front of the jaw with well developed lower tusks/incisors, from the Late Miocene onwards, many groups convergently developed brevirostrine (shortened) lower jaws with vestigial or no lower tusks,[2] probably corresponding with the elongation and increasingly dexterity of the trunk allowing it to be used as the primary feeding organ.
Cladogram of Elephantiformes after Li et al. 2023, showing a paraphyletic Gomphotheriidae.