Mexican trip - second part

On the third day of our trip, we headed towards Jalpan on the MX70, but turned off at El Sauz, and explored some rocky outcrops, to find:


Mammillaria wagneriana


Close up of spines of M. wagneriana


View of habitat

After El Sauz we found many more Mammillaria pettersonii, but also on the other side of the road, what is most likely to be Mammillaria pettersonii v. huiguerensis in abundance, with large groups of big woolly heads. (amended after discussion below in thread).


A different form of Mammillaria pettersonii


Close up of that plant of Mammillaria pettersonii


A rather large plant of Mammillaria pettersonii


From a bit further back this time


Mammillaria pettersonii v. huiguerensis - my GPS is 11cm long, so judge the size of these heads!


Close up of the plant

We went on to the village of El Maguey, and explored the cliffs to the left of the village, eventually finding Mammillaria bombycina. I have a plant in my collection that is called M. bombycina from Colomas, and as we drove on, we passed through Colomas within a couple of km of where these photos were taken. These plants are a little different from many seen in collections, but a very good match for my plant.


Mammillaria bombycina


A nice group of M. bombycina


A flower on a head of M. bombycina

We then followed the road through Jerez, towards Fresnillo, and stopped to explore a deep ravine. We passed Mammillaria pettersonii and Mammillaria heyderi ssp gummifera plants on the descent to the almost dry river bed, and then asceded to find Mammillaria densispina, often growing in moss on rocky outcrops.


Mammillaria densipsina


Mammillaria densipsina


Mammillaria densispina growing in moss


Another moss rooted Mammillaria densispina

That's probably all now for a few days, look for more early next week.

Again, pretty pictures and thanks for sharing. On your third picture you wrote M. parkinsonii. I think this was misspelled and should read pettersonii as parkinsonii is much different.

Thanks Amante. Did you mean the 3rd picture? or the 8th? The one which has many big heads and lots of white wool, 2 black slightly curved centrals and about 8-12 pale radial spines, doesn't conform to the description of pettersonii, but is closer to that of parkinsonii - not exact by any means, as the spines are much shorter and darker. I did wonder about M. gigantea, but that is sipposed to be solitary, and is again rather different, based on books and my own plants. I do wonder if I have the name right for this plant, so all help would be very welcome.

Yes. It is the 8th picture, sorry!! At that size M. parkinsonii should
split dichotonomously (hope I wrote it well). I have seen parkinsonii
in habitat and it varies a lot but still it is very different from your
picture. So I would rule out parkinsonii. M. gigantea would fit more.
If it was from SLP I would say it is M. orcuttii. Check your picture
with Pilbeam book of M. orcuttii and they are quite similar. Still I
have not compared the number of spines, etc.

Having said that, the question remains whether your plant/s is a multiheaded clump or a solitary species that happened to grow together due perhaps to water or ants or seeds falling in the same area. Were there more plants of this species or it was just this one pictured?

I would agreed with Amante that the 8th picture is a possible M.gigantea. Althought I cannot find it at the moment the plant does look like a yellow flowered from of gigantea, collected by Rogozinski, of which I am sure has been shown in the AfM jounal.
Perhaps if you sent the picture to Wolfgang he would be able to clear the matter up.

Thanks Chris for the nice photos and the trip report!
I am certain that the 8th photo is not M. parkinsonii. It has the looks of M. gigantea, but based on the location where you found it (well out of gigantea territory), I think that it is a very pretty, short spined form of M. petterssonii.

Wolter.

Thanks to all onthis question. I am in agreement with you all that it isn't parkinsonii. If pettersonii then it has much too few central spines, unless the description is out of date and needs updating. We were a good way from SLP, so I do rule out orcuttii.
But 2 centrals, lower curving, and about 8-10 radial spines is a good way from any of these descriptions:
gigantea 4-6 centrals, up to 12 radials
pettersonii 6-7 centrals, 10 or more radials.
So for me it is still a bit of a mystery, although an aberrant form of pettersonii could be the explanation, based on locality.

Why do those M. bombycina look so different from mine? Those spines look more... Yellow.
Is mine not M. bombycina?

Hi again,
Yes, your plant is M. bombycina without doubt. I have a plant just like yours.
The spine colour appear to vary a lot across its distribution range. Where we saw it was near a town called Colomas (in fact at a village called El Maguey). I bought a plant a couple of years ago called M. bombycina v. Colomas, whch I thought was really rather different, and also saw that the German company G. Koehres sells seed of this form. It is very similar to what we found. Since then I have acquired two other forms of this species, MK 176-492 and ML316, all of which show different spination yet again.
According to the New Cactus Lexicon, perezdelarosae is a subspecies of bombycina, and v. andersoniana (the straight spined smaller form) mereley a local variant. I think they are sufficiently distinct to be separate species, but a German friend sent me a photo (which I can't find at the moment) of a plant he found which he calls "bombyrosae" as it looks to be between the two species.
If only nature conformed to our need to compartmentalise things, life would be so simple

Does the German Company shipped seed to the USA?

There was a thread on The Garden Forum where someone posted images of the straight spined perezdelarosae as well as a golden spined form. Very nice looking plants! (Mammillaria perezdelarosae on TheGardenForums)

I don't know if they do ship to US, but anyway, I just checked and the seed is no longer listed.
Plants are available from Southfield Nurseries in the UK, but that's no use as I don't think they don't ship to US, permit problems etc.

Oh well

I'll have to wait until someone I know has a plant that produces seeds.

But I'll keep looking

Thanks for even checking
Paul

By the way, Did you see the images on that other thread I posted the link for?

Nice plants

Hi Chris,

While looking through the second issue of this years' German Mammillaria journal, I noticed a photo on p. 98 which shows a plant which looks very, very similar to the plant of your 8th photo (M. parkinsonnii - M. gigantea - M. petterssonii). The plant is labelled M. huiguerensis Rog 299 from Presa de los Serna, which lies a little southwest of Calvillo.

Wolter.

Hi agree, Wolter, that this plant Rog299 does look very much like the plant that I showed (#8 in the sequence). I am surprised at the attribution of huiguerensis though. I think that this name is a Reppenhagen name (#263 in his book, 2nd volume), which comes from La Huiguera, Zacatecas, about 14km as the crow flies from Presa de los Serna, and 27km from where I saw my plant. The Reppenhagen plant appears to have rather longer central spines (11-30cm is written). I have two of these grown from seed, and they both have the longer and rather untidy spines much like those in the Reppenhagen book.
I know that spine length and even colour varies a lot in habitat, so it is quite possible that this is the same species but just a shorter spined version - everything else matches, I think, in terms of number of radials and centrals, and the description of the lower central as being longer and sometimes curved.
OK, so I think we have the name. Many thanks, I'm going to edit the thread and change it accordingly.