Look at sheldoni.

Hi all!
I sowed the seeds m. sheldoni. First, the center hook barb was twisted counterclockwise light. A year later, the new center spines changed to straight, dark. I had not noticed this behavior for m. sheldoni - swinglei. This is normal?









In addition, another photo of the mysterious stranger. M. sp. Obregon.


M. angelensis?

Vladimir.

In the title of the topic should be read Sheldonii.
Bug fixes not yet learned.

Add a photo sp. Obregon in the sunset.
Bush grew up.


Vladimir.

hi for your sp

in SONORA state - Obregon in fields numbers search i found only 2 mam :

Werner Reppenhagen – Rep 2105 – Mammillaria sheldonii – MEXICO – SONORA — Obregon — 90 m

Werner Reppenhagen – Rep 570 – Mammillaria sheldonii – MEXICO – SONORA — Cuidad Obregon — 70 m

so nothing else in this area than Mammillaria sheldonii reported

The variation in the spines of M. sheldonii is very large. I visited Sonora in 2010 and found a number of populations of M. sheldonii, some with hooked spines, some with straight spines, some with no central spines or very short straight ones, some with yellow spines, some with brown spines and some with white spines.

In San Carlos Bay, I found plants with straight spines and some with hooked spines. Some were in seed, and I took one seed pod from a straight spined plant. Back home, I sowed the seed and got some seedlings, which all had hooked spines. I passed most on, because I was disappointed, but kept a couple. When the seedlings were 2-3 years old, they stopped producing hooked centrals and produced straight ones.

If the botanists are right, M. sheldonii is very closely related to M. grahamii, and of course there is a straight spined form of this also, sometimes called v. oliviae.

Dear Franck and Chris!
Thank you for your help.
In a broad sense, these are mamm's sheldonii.
They, obviously, "dark past".  
Only sp. Obregon has a relative home.
Image Rep 2105 and Rep 570 I have not found in my PC.
Maybe someone will take pity and lay out their photo?
I posted Obregon and angelensis in the same conditions, observe what happens. It may be that they are "sisters".
Vladimir.
PS. Olivia as Olivia. Get.

and remember also Luthy classification that include M. sheldonii and M. swinglei
under M. mazatlanensis

What you have on the mainland are hooked spined plants which seem to start (or end?) in Sinaloa (M. mazatlanensis) and end (or start) in the southern USA states of California, Arizona, New Mexico, etc. (M. grahamii, M. oliviae, M. microcarpa....), with Sonora (M. sheldonii, swinglei, alamosensis, guirocobensis.....) in between.

How you decide to "split" this spectrum of forms into distinct species depends on what you think defines a species. Botanists tend to have one set of views, tending towards what we call "lumping". Amateur enthusiasts often look for differences rather than similarities, and so tend towards "splitting". Nature, of course, doesn't recognise these distinct boundaries, but we humans seem to like to label things.

My personal preference is to keep M. mazatlanensis separate, and treat M. sheldonii (and all its derivatives) as a Sonoran plant, and M. grahamii as a USA plant, while recognising that there will be transitional forms. As well as a name, I do like to know where the plant originated from, either a collection number or a locality.

Thank you.
The wife says:
- Your cactus euphoria could turn into an attack on the heart or schizophrenia!
What to do if you want to.

I think that these "Sisters Sheldon" mixed back in the 90's to me.
I had the idea to create the layout of the Mexican cacti and place according to the spectrum of their relationship. Having trouble finding the right plants. And the living area does not allow. This requires a "Hangar 18" like Lisa!   I will put in alphabetical order. Gone visibility, it has become more convenient.
My Patonii more elegant than sheldonii. (all 9x9 cm).
Like this.



- 4 C.

So sometimes I want to drop everything in one pot with tag "КАКТУСЫ".
Vladimir.