Acanthocereus paradoxus (2021)
By Pat Mahon (February 2020)

Just when we thought there couldn’t be any more cacti to be found … another species pops up in Jalisco, Mexico. Described in November 2020, Acanthocereus paradoxus has the slender stems of the similar-looking Peniocereus greggii, sporting a tuberous caudex base and even bearing a large night-blooming flower of similar shape. To the untrained eye during the day – when it is NOT blooming – it could have easily been overlooked. This is likely how many new species are being discovered: looking between the lines.
Acanthocereus paradoxus so far has a limited distribution in Mexico and seems to be locally endemic. Perhaps, in time, we may see this species in cultivation. But in the meantime, there are other similar-looking Acanthocereus species available, or the reliable Peniocereus greggii.
For these species, a balance between good sun and some shade needs to be practiced. The withholding of sunlight can inhibit blooming, which is the highlight of these cacti. In nature, they tend to grow in association with scrub and trees, which provide good protection from the sun. They can be susceptible to sunburn, so watch the bodies of these plants! Well-draining soil is pretty much the standard with most cacti, but with tuberous growths, it can really prevent rotting.
Sources:
Phytotaxa, November 2020 – Acanthocereus paradoxus (Cactaceae), a New Endemic Species From Jalisco, Mexico
https://www.researchgate.net/publication/345632590_Acanthocereus_paradoxus_Cactaceae_a_new_endemic_species_from_Jalisco_Mexico/link/6013164592851c2d4dfecef5/download
Wikipedia – https://en.wikipedia.org/wiki/Acanthocereus
SFGATE – How to Take Care of Night-Blooming Cereus – https://homeguides.sfgate.com/care-night-blooming-cereus-45019.html