Location: South of Matehuala, S.L.P.

Ariocarpus retusus LRM183, growing within a few metres of A. hintonii.

Comments

This population represents one of the few locations where Ariocarpus spp. are found sympatric, A. retusus and A. bravoanus subsp. hintonii were observed within 10 metres of each other, no evidence of hybridization was observed, it appeared that the A. retusus flower a few weeks prior to A. hintonii. A. retusus appears to prefer the higher parts of the hill., A. hintonii was more prolific lower down the slope. (see also A. hintonii (Matehuala)) These plants are probably correspond with what Halda has described as A. retusus subsp. horacekii, the type locality of which is on the next hillside.