The distinction between Opuntia stricta (Haw.) Haw. and O. anahuacensis Griffiths may be sometimes straighforward but the latter is often not recognized in floras and electronic databases as an independent taxon.
At least in the Mediterranean basin it seems that there is a rather precise zonation of the two species.
I think that measurements on various morphological characters on a sufficiently large number of specimens could allow to support the recognition of the two taxa as different species. As regards, I have drawn a preliminary list of possible characters.
Where I live plants corresponding to the concept of O. anahuacensis are predominant, while in western Mediterranean it seems the opposite.
I am wondering if there are some volunteers from the locus classicus (southern Texas) and western and central-eastern Mediterranean to join a research group to try to make such study.
Whoever thinks to be able to help in any manner is welcome.
Also comments and suggestions are welcome.
Feel free to forward this post to anyone, provided that this person is willing to help.

I hope not to have bothered you with this post and thanks for the attention.

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