For a little prologue to this post, see the preceding one: Kalanchoe integrifolia).
Although Mt. Ibity is perhaps the most accessible place, P. brevicaule also occurs in a couple of other habitats in Madagascars central highlands.
Plants can be found from Ambositra to Antananarivo in quartz rock at altitudes between 1400 and 1600 m.
In some spots where P. brevicaule grows together with P. densiflorum or P. rosulatum, one can come across hybrids. Judging from the long flower stalks, I suppose the plants shown in pictures # 3 and 4 belong to either of these hybrids.
The first two pictures show views from where P. brevicaule grows on Mt. Ibity. On # 2 you can see the quarry belonging to the massive cement factory nearby.