One of the two varieties of Pachypodium baronii. The P. baronii varieties are one of the most striking and beautiful members of the entire genus. They are the only two with striking crimson red flowers. The two varieties, endemic to Northern Madagascar, are separated only by around 150 miles from each other. This one, P. baronii windsorii, is found in the Windsor Castle vicinity, which is a large limestone outcropping. It is smaller and more compact than P. baronii baronii, and has shorter flower peduncles, red petals with a yellowish throat. It is extremely rare and desirable in collections.