The overwhelmingly large genus Geochelone was split up over a decade ago and this is now followed The checklist when looking for justification does require you to have all versions to follow it along the  version discusses Geochelone the  and  versions discuss the reasons for using Aldabrachelys over Dipsochelys and the most recent  version just refers to their old discussions in previous versions Under the rules of the ICZN the valid name is Aldabrachelys prevailing usage until a decision is made by the ICZN regarding the current case over this species Cheers