Ancient historians such as Polybius describe these forces already in action rather than describing their formation, so the earliest surviving mention of each force is not evidence of when it actually began; both evolved gradually out of longstanding recruiting and alliance practices rather than being founded on a known date.
What would resolve this Archaeological or epigraphic evidence documenting Carthaginian military organization, or Numidian cavalry service to Carthage, earlier than the surviving literary sources allow.
OpenAncient history and archaeologyWikipedia: Military of Carthage