urus ▁in ▁ 1 9 9 8 , ▁and ▁Tsch opp ▁rec lass ified ▁it ▁as ▁Br ont osa urus ▁y ahn ah pin ▁in ▁ 2 0 1 5 . ▁ ▁Classification ▁ ▁A pat osa urus ▁is ▁a ▁member ▁of ▁the ▁family ▁Di pl od oc idae , ▁a ▁cla de ▁of ▁gig antic ▁sau rop od ▁din osa urs . ▁The ▁family ▁includes ▁some ▁of ▁the ▁longest ▁cre atures ▁ever ▁to ▁walk ▁the ▁earth , ▁including ▁Di pl od ocus , ▁Sup ers aur us , ▁and ▁Bar osa urus . ▁A pat osa urus ▁is ▁sometimes ▁class ified ▁in ▁the ▁sub family ▁A pat osa ur inae , ▁which ▁may ▁also ▁include ▁Su uw asse a , ▁Sup ers aur us , ▁and ▁Br ont osa urus . ▁O th n iel ▁Charles ▁Marsh ▁described ▁A pat osa urus ▁as ▁al lied ▁to ▁Atl ant osa urus ▁within ▁the ▁now - def unct ▁group ▁Atl ant osa ur idae . ▁In ▁ 1 8 7 8 ▁Marsh ▁raised ▁his ▁family ▁to ▁the ▁rank ▁of ▁sub order , ▁including ▁A pat osa urus , ▁Atl ant osa urus , ▁Mor osa urus ▁(= C amar as aur us ) ▁and ▁Di pl od ocus . ▁He ▁class ified ▁this ▁group ▁within ▁Sau rop oda , ▁a ▁group ▁he ▁ere cted ▁in ▁the ▁same ▁study . ▁In ▁ 1 9 0 3 ▁El mer ▁S . ▁R ig gs ▁said ▁the ▁name ▁Sau rop oda ▁would ▁be ▁a ▁junior ▁syn onym