Is this a matucana madisoniorum v. horridispinum bud

[ImNotTelling]

Spotted it yesterday...

[DaveW]

Yes it's a bud. In fact coincidentally my M. madisonorum is producing an adventitious but half way down the stem this year in addition to the normal buds at the crown. I await to see if it develops or just eventually aborts.

I don't think the variety horridispinum has ever been validly published, therefore it is probably just a name Karel Knize dreamt up. M. madisoniorum plants vary as to how many and how quickly deciduous their spines are, since unlike many cacti most spines eventually fall off lower down the stem and this is perfectly normal. This lliffe link simply shows a small immature plant where the spines have not had time to drop off yet.

http://www.llifle.com/Encyclopedia/CACT ... rridispina

http://www.cactus-art.biz/schede/MATUCA ... niorum.htm

This was mine last year. As you can see a few spines are retained even in old age:-

M.-madisoniorum.jpg (60.02 KiB) Viewed 783 times

Matucana madisoniorum v. pujupatii is a spinier plant tending to retain them in old age therefore probably there is a cline from virtually spineless to spiny plants in the species? M. pujupatii also tends to offset whilst young.

http://llifle.com/Encyclopedia/CACTI/Fa ... _pujupatii

[ImNotTelling]

I am not going to refer to it as pujupatii, because it just doesn't resemble it at all as a subspecies. Also, relevant to some sources/databases like catalogue of life(at least when I looked it up)
To compare my 2 matucanas
a), plain madiosniorum, which i got a year earlier(grown at a different location).

and b) horridispinum

which is much more tuberculate, and has consistent spines...
But yes,thanks for the confirm.

[DaveW]

Yes it's certainly M. madisonorum and not v. pujupatii which is quite different in growth.