Yesterday we had solved the puzzle of how to get to Geohintonia mexicana and Aztekium hintonii, at least in theory. We returned full of confidence and continued S2285 with images from La Poza up the track suggested by SatNav. It was not the widest of tracks – OK for one car at the time but two cars coming from opposite directions need to negotiate an overtaking spot, with steep drops to one side and the rocky cliff face on the other.
S2286 saw us arrive at a convenient roadside parking place some 400 m (according to SatNav) from the plants. Particularly when you are surrounded by masses of rocks, GPS systems can get a little confused when you’re practically on top of the coordinates. So it took a while before we were convinced that we were on the exact spot – no plants here. So we switched over to ‘manual’, or rather using our instincts. This took me to the top of a slow rising hill made of ‘white stuff’ lime stone or gypsum. It was very soft so that it was easy to see where water and hoof / foot prints had worn out paths. There were lots of tall Yucca and pine trees around – I guess the pine needles bring acidity to the very alkaline lime stone rocks. They make the rocks very slippery! Other vegetation on the rocks included the resurrection plant – Selaginella lepidophylla, looking from a distance like small globular cacti hanging from the cliff face. Half way up the hill I realised that some of the globular objects were in fact cacti – but not the ones that we were looking for. Nobody who has reported visiting this site mentioned other cacti – yet they are obvious to see, closer to the road. They do not look like typical Neolloydia conoidea, may be a Thelocactus conothelos form? A Coryphantha sp.? Time will tell. But where were the stars of the show? Nowhere to be seen.
The late Keith Grantham had visited these plants in habitat during a Charlie Glass lead IOS expedition in the 90s. His pictures appear in The Plantfinders Guide to Cacti and Other Succulents as few of the habitat pictures. I was sure that he mentioned having to walk into a narrow canyon and sure enough there was such a canyon. It was a warm 27 C (80 F) on the exposed hill but near the canyon there was a nice cooling breeze. I was about to suggest trying a different spot when there, at my foot was a 4 cm (1.5″) globular cactus – G. mexicana!
I yelled my success to Eunice, some 100 m. behind. I indicated the size and where the plant was, which prompted her to look over the edge of the path where she stood: there was a group of seven plants right there! We spent at least an hour over this hill side, including my clinging on to narrow ledges to get face to face with the cacti. Only from close up could I tell the Geohintonia from A. hintonii. The farther we went into the canyon, the denser the plants grew together. There were a good few out of focus pictures in my shots, due to the gymnastics I had to perform to get near them. Eunice was more sensible and took equally good shots from near the foot of the hill.
Mission accomplished, we decided to find the excellent Highway 57, the main road south and head to Matehuala, crossing the border into San Luis Potosi.
We made one more stop, S 2287, for a forest of tree-like Yucca and a leg stretch. There were some of the usual Opuntia, but also some plants that might be Echinocactus horizonthalonus. I was thrown by an a-typical specimen growing in the shade of a large Yucca. Whatever it is, it wins my prize for ‘best spination’ today (or probably this year! reminding me of Copiapoa echinoides near Totoral in Chile that had some very heavy spines.
Matehualla is a convenient town for a couple of days more exploring and we found the comfortable Las Palmas hotel right along the highway. Comfortable chalets, good restaurant and bar plus wifi in the rooms. Great. From here we’ll visit Aramberri and Dr. Aroyo etc. and the cactus locations that they’ve become famous for.