To confirm the registration of an Australian native hybrid & view its composition/progeny: (Database as at 1st January 2020 RHS registrations)
For non-Australian Dendrobium hybrids use the Dendrobium Hybrids checklist here
Sarco. Misty= Aussie Dawn x Riverdene ( has 6 hybrid progeny ) registered: 19/01/2001 by Butler D.F.
Species composition summary:
Sarco. Misty = Aussie Dawn x Riverdene = [hartmannii x dilatatus] x [hartmannii x hirticalcar]