Mammillaria dealbata

There are two different plants in my collection, but with the same label....
The first from Uhlig-Kakteen.

Mammillaria dealbata - N.1










Could it be near this description?

Description from "Mundo de las Cactaceas" Helia Bravo Hollis:
Mammillaria dealbata Dietrich, Allg. Gartenz. 14:309.1846 (non sensu Britton et Rose).

Cactus dealbatus Kuentze, Rev. Gen. PI. 1:260,1891.

Tallo robusto, cilindrico.
Tuberculos fuertemente subcomprimidos, obliquamente truncados, verde-grisaceus. Axilas subnudas, Areolas blancas, tomentosas, despuedes desnudas. Espinas radiales 24 a 26, muy tenues, suberecto-radiantes, niveas. Espinas centrales 2, muy robustas, blancas, pardas, esfaceladas, la superior mas corta, erecta; la inferior mas larga, aplanada, deflexa.
Localidad tipo: desconocida.
La descripcion anterior esta tomada da Salm-Dyck (Cact.Hort.Dyck. 1849 89, 1850). quien agrega:
"Tallo, hasta ahora, simple. Muy cercana a M.parkinsonii de cual defiere por tener 2 espinas centrales".
La breve incompleta descripcion no nos permite identificar plenamente esta especie, pero, a juzgar por el comentario de Salm-Dyck, la planta de su colecion, que el identificò como Mammillaria dealbata, partenecia, sin duda, al complejo de M.parkinsonii.



Mammillaria dealbata  -  N.2















Could it be near this description?


Description from "The Cactaceae" Britton & Rose:

62. Neomammillaria dealbata (Dietrich).
Mammillaria dealbata Dietrich, Allg. Gartenz. 14: 309. 1846.
Cactus dealbatus Kuntze, Rev. Gen. Pl. 1: 260. 1891.
Globose to short-cylindric, glaucous, more or less depressed at apex but almost hidden by the
many closely appressed spine-clusters; axils of tubercles and young spine-areoles densely lanate but
in age glabrate; radial spines about 20, white, short, appressed; central spines 2, much stouter and
longer than the radials, sometimes 1 cm. long, the upper ones often erect, white below, brown or
black at tip; flowers small, carmine; fruit clavate, red; seeds brown.
Type locality: Mexico.
Distribution: Central Mexico, especially on the pedregal about the City of Mexico.
We have referred to this species a plant which is very common in the Valley of Mexico
and which is known in collections as Mammillaria peacockii. The name, first used by
Rümpler (Förster, Handb. Cact. ed. 2. 286. 1885), was given as a synonym of Mammillaria
dealbata. It was offered for sale by Grässner as M. elegans dealbata (Monatsschr.
Kakteenk. February 1920).

Hi maurillio,

I would say your second plant was closer. M. dealbata refer to m. haageana ssp. san-angelensis.

I don't think the second plant conforms to any of the descriptions. Both refer wooly axils and areoles when young and the second plant is completely lacking in that department.

The first description, on the other hand, is evocative of a M. parkinsonii, especially considering the central spine configuration.

I was not taking any of the descriptions into account, but purely on the photo evidence. In my opinion the second plant conforms well to my perception of m. haageana ssp. angelensis (m. dealbata). See Pilbeam's Mammillaria page 125.

I agree, Derek. I was replying to Maurilio's question as to the conformity of his plants to the descriptions given.

This discussion shows, in my opinion, the difficulty of identifying plants without known pedigree.

First of all, you have a brief description which is of no real value. Then you get a better description which does not even give a habitat location. Neither of these are close to the plant that Maurillio shows as his #1.

Finally we have a third description, from Britton and Rose, supposedly a translation of the Kuentze description, but clearly not! It says that the axils are lanate, whereas the earlier description says almost naked (subnudum). It adds that later on in life the axils lose their wool. It also says the plant has 2 central spines, the lower one the longest. It also now adds a general locality.

I believe that with descriptions that vary significantly, we cannot sensibly keep the name dealbata as a recognised name. It has, in any case, now been subsumed into the species, M. haageana, as have all previous varieties and subspecies.

I haven't been into the Mexico state central valley from where the so called subspecies purports to come, but I have seen a number of different M. haageana plants in Puebla. Here I saw plants with 1 central spine; 2 central spines; 4 central spines; some all white spined, some white with dark tips; some with almost totally dark central spines; some with centrals that were smooth and glossy; some with centrals that we dull and rough looking.

While I don't support Dr Hunt on all of his reductions, this one seems right to me, as in Puebla I could not really ascertain any obvious geographic isolation of forms,, which is an essential requirement in my view of separating out a subspecies or variety. Otherwise they are just local forms.

Additionally, coming back to my first point about pedigree, I wonder how many generations the plants shown are from the original habitat plant (or seed) that was collected. Was purity maintained?

Don't get me wrong, I have no problem with growing undocumented plants - it is just that trying to associate somewhat suspect names with them makes no sense to me at all.

My two M.dealbata are really undocumented plants, but marketed by two believable greenhouses,
"Uhlig-Kakteen" and "Il sole rarità botaniche".
I did not want to have an identification.
I have only tried (unsuccefully) to couple two different plants to two different descriptions, all 4 indicating Mammillaria dealbata.
Helia Bravo speaks about M.dealbata near M.parkinsonii, Britton and Rose near M.elegans.
We have also a third description by Sanchez-Mejorada reported at pag.125 by Pilbeam in "Mammillaria" mentioned by Derek....

Solitary, globose or shotly columnar, 6 to 12cm tall, 4 to 7cm in diameter, axils wolly in youth.
Radial spines 18/20, needle-like, white 5 to 7mm long.
Central spines usually 2, or 1, awl shaped, white, darker at the tip, 5 to 6mm long.

The third description for the same epiteth......... for sure is correct Chris when he write...
  "we cannot sensibly keep the name dealbata as a recognised name."
I would like if someone could show the pictures of m.dealbata in his possession.
Even more if plants with source data.

At the same time a great "grazie" for your suggestions.