Subspecies, varieties, forms and cultivars of plants belonging to the Cycas arnhemica group

• Cycas arnhemica K.D.Hill: has longer leaves with broader and more widely spaced leaflets, 5-6.5 mm wide and distinctly angled towards the leaf apex. Distribution: around the Goyder river in central to eastern Arnhem Land.
• Cycas arnhemica subs. muninga Chirgwin & K.D.Hill: has larger cones and seeds over 32 mm wide. Leaves crowded and numerous. Leaflets slender, 3.5-5.5 mm wide and more or less perpendicular to the rachis. Distribution: known only from Groote Eylandt in the Gulf of Carpentaria.
• Cycas arnhemica subs. natja K.D.Hill: has smaller cones and seeds under 32 mm wide. Leaflets slender, 3.5-5.5 mm wide and more or less perpendicular to the rachis. Distribution: north coast of Arnhem Land (lower Blyth River to Elcho Island).