Biology and generic limits
The revision by Rosas-Reinhold and colleagues combined chloroplast markers, field observations and niche models. Two principal lineages corresponded to Aporocactus flagelliformis and A. martianus. Variation formerly described under five names fitted this division. [Rosas-Reinhold et al. 2022, full source text, discussion of results]
In the studied populations, the northern species mostly had pink to magenta zygomorphic flowers, whereas the southern species had red actinomorphic flowers. Both occupied cloud and pine–oak forests. The combination of colour, symmetry and provenance is diagnostically more informative than a single character. [Rosas-Reinhold et al. 2022, full source text, discussion of results]