Mammillaria gasseriana / wohlschlageri

I have these three species, grown from seed:


Mammillaria gasseriana "Ojo de Agua", Piltz seed.


Mammillaria wohlschlageri SB1965, Hajek seed.


Mammillaria wohlschlageri RS450, Succseed seed.

I find this very confusing. M. wohlschlageri SB1965 seems to be very close to my M. gasseriana "Ojo de Agua" (except for the hooked central spines), and M. wohlschlageri RS450 seems to be completely different from SB1965, even allowing for some natural variation. What are your opinions on this?

I think the odd one out of the plants without hooked central spines is SB1965 which comes from Ignacio Allende, Durango some 230kms north west of Fresnillo, Zacatecas which is where M. wohlschlageri is supposed to come from. Your plant looks like mine and the Durango plant is something else in my view.

There are a multitude of Ojo de Agua places names in Mexico, but looking at my field lists there are quite a few entries for gasseriana with that location name that are from Durango. I can't find a state for the Piltz seed. My understanding is that M. gasseriana (and synonyms chica and viescensis) are from Coahuila. Hooked spine plants in Durango are most likely to be M. stella-de-tacubaya, though it gets confusing because the presence of hooked spines seems to be a variable feature.

It may be that M. lasiacantha ssp. lasiacatha is from Texas, New Mexico and northern Coahuila and Chihuahua; M. gasseriana from Coahuila and has thin central hooked spines; M. lasiacantha ssp. hyalina from around Fresnillo Zacatecas; and M. stella-de-tacubaya (in both thicker darker hooked spine form and forms without central spines) are from Durango.

Wolter ten Hoeve did a detailed analysis some years ago after extensive field work, on which my views above are based (from memory). I'm sure he will have something valuable to comment on this.

Mammillaria gasseriana Ojo de Agua is the same as M. stella-de-tacubaya Villa Insurgentes. Ojo de Agua and Villa Insurgentes are two nearby villages, on the western edge of Zacatecas, along the Fresnillo - Durango road. In the past, the Germans often called the mammillaria from this region M. gasseriana Ojo de Agua, but later on, they referred to it as M. gasseriana Villa Insurgentes (e.g. PN 286 and PN 531). Helmut Rogozinski for many years also named it M. gasseriana Villa Insurgentes in his travel reports, but in his recently published field list he has changed it to M. stella-de-tacubaya Villa Insurgentes (Rog 04, 78, 511). My own plants of this Ojo de Agua/Villa Insurgentes taxon have never produced hooekd centrals, but long ago I once read that someone in Belgium also got a few hooks on his Ojo de Agua/Villa Insurgentes.

M. wohlschlageri SB 1965 cannot be a wohlschlageri, it must be M. stella-de-tacubaya (or M. gasseriana, if you want to stick to the old - wrong - name). Ignacio Allende is stella-de-tacubaya territory. I found stellas at Yerbanis, 30 km north of Ignacio Allende (I have never observed hooked centrals on my Yerbanis plants), Rogozinski reports stella-de-tacubaya Rog 79 from Luis Moya, less than 10 km north of Ignacio Allende. He writes in 1988: hardly any plants of stella-de-tacubaya, whereas in 1986 there were many of them.
In my article I wrote the following: "Interestingly, Mesa Garden lists M. wohlschlageri SB 1965 from Ignacio Allende (30 km south of Yerbanis) in its seed catalogue (MG 951.7). Seed-grown plants of this taxon develop some short hooked central spines. Based on the formation of these hooked spines, on the location of this taxon and on the appearance of the young plants, I conclude that this taxon is not M. wohlschlageri but instead it is akin to the taxa under consideration in this section" (i.e. akin to M. stella-de-tacubaya).

RS 450 is indeed wohlschlageri (or lasiacantha hyalina if you want to follow Hunt). Looking on the Cactus and Succulent Field Number website: RS 450 is from Fresnillo, which I think is the original wohlschlageri location.

Wolter ten Hoeve.

Thank you, Chris and Wolter. I shall change my SB1965 plant to M. stella-de-tacubaya.
I have another M. gasseriana stella-de-tacubaya "Ojo de Agua" plant that has sprouted 3 heads after some damage to the apical meristem, and while 2 of the heads have the same hooked centrals, the other has none.