The Cactus Trip Diaries

After last night’s great stop, S3200, where we found a very variable selection of Ariocarpus (A. confusus), we had high hopes to continue the theme with another stop at a location where these Ariocarpus had been reported from, near La Escondida (S3201). Here the range of flower colours had been reported to include yellow and yellow-with-pink-tips to the petals. We had no problem finding the hillside, right along the side of MEX 61, but failed to find ANY Ariocarpus at all on hill, and the one behind it and the hills to the left and the right of our target location, which in itself seems a bit odd as just about every hillside here seems to support Ariocarpus plants – still, never mind!

There were many Echinocactus platyacanthus here and many of these had been badly damaged, some by animals (Donkeys? Goats? Cattle?) while others looked to be damaged by disease. Could such a disease have whiped out the Ariocarpus here?

There were still plenty of other cacti to see, with of course Opuntia and Cylindropuntia as always omnipresent in large numbers. I was quite excited to find a small cactus where the stem was very thin just above the ground, broadening to a normal globular plant. Might this be ‘Gymnocactus subterraneae’? Pictures were taken, just in case. Moving on, I then found similar plants, but larger, resembling Neolloydia conoidea, so that my small plant was probably nothing more than a juvenile plant of this taxon. It does seem that Neolloydia are much more variable than I had appreciated – something to look into back home on cold winter evenings.

Just as at S3200 yesterday, there was a large presence of Thelocactus connoideus around. If I’m ever back here in spring, they’d be worth a stop when in flower. And to cheer Alain up, there were some more ‘Red Devils’ (Ferocactus pilosus) hiding among the shrubbery, even though the plants were up to 2 m tall.

Time to move on and as we approached the turning to Sandia and La Solidad that we had missed last time that we drove by here, the walkie talkie crackled and Ian offered to take us to the site that they had found on that occasion, where large Thelocacti grew (S3202). T. conothelos subsp argenteus has been reported from here and pictures in John Pilbeam’s Thelocactus book seem to match what we saw. Others used to name T. macdowellii, but this plant is reported from farther north, near Monterrey, and the one large plant that I have owned and killed under that name had finer supination and formed a clump while the plants that I saw here were all large solitary heads, with one offsetting exception. More things to look up!

For completeness sake I should mention Mammillaria formosa and Echinocereus enneacanthus, plants often found at our stops but not always mentioned. Another Echinocereus here was what I’ll call E. pectinatus with beautiful fine spination. Talking of things I need to look up: how can I tell E. pectinatus from E. riggidissimus from E. reichenbachii in habitat? Geographical taxonomy?

Echinocereus pectinatus ? (S3202)

We had deicided to take the ‘back road’ from Dr. Arroyo to Tula, as Ian’s map described it as a ‘big yellow’ road, but turned out to be a variable dirt track which did not help my back at all – yep, the disc popped again.

The last two stops were therefore ‘leg stretch’ stops with nothing new seen.