Micranthocereus auri azureus

[James Pickering]

..... and here

Micranthocereus densiflorus (syn. Micranthocereus flaviflorus var. densiflorus)

[James Pickering]

Micranthocereus streckeri

[discolover]

James, very nice plants and lots of flowers!
Do you agree with me that the plant of Richaud is a Micranthocereus polyanthus and not M. auriazureus?
I'm still searching for Micranthocereus uilianus.
Do you have plants (and maybe seeds) of Micranthocereus uilianus?
I have not been able to find plants (or seeds) of this species.

Peter.

[James Pickering]

James, very nice plants and lots of flowers!
Do you agree with me that the plant of Richaud is a Micranthocereus polyanthus and not M. auriazureus?
I'm still searching for Micranthocereus uilianus.
Do you have plants (and maybe seeds) of Micranthocereus uilianus?
I have not been able to find plants (or seeds) of this species.

Peter.

Thanks Peter. First let me say that I have never been very good at attributing cacti when there are unusual deviations from the norm such as color of the epidermis and spination. It does seem to me that Richaud’s plant flowers conform more to M. Polyanthus than M. auri-azureus, although the spination seems to conform pretty well. But I have not been successful in locating reliably attributed cuttings or seed of the latter to offer a comparison. I did obtain some seed purported to be M. auri-azureus several years ago and managed to raise a few plants to flowering size:





..... the flowers seemed right but the spine coloration and form did not — as you point out (and as depicted in the excellent “plants in habitat” link you provided) the stems/spines should be somewhat golden (per the name). I only had three plants and they froze in an unheated greenhouse here during a February cold spell. So this species remains elusive for me.

BTW, Peter, all of my cereoid(?) cacti, except for the miniature Arrojadoa dinae, are housed in an unheated greenhouse at (my friend) Dan Bach’s Cactus Nursery here in Tucson (I am now strictly a windowsill grower at my town home - I have great difficulty walking these days). I only visit them three days each week. I mention this because I intended to post pics of my first Micranthocereus polyanthus subsp. alvinii plants in flower yesterday but forgot to take pictures . I will do that tomorrow and post them here.

[James Pickering]

As promised, Micranthocereus polyanthus ssp. alvinii:





..... at least that is what they are supposed to be. After researching on the web, there seems to frequently be some confusion with nomenclature and attribution. The plants Depicted here are about two years old from seed - I forget when they were planted (my memory - and record keeping - is pretty bad these days). Pics taken yesterday afternoon.

James

[James Pickering]

Coming full circle, as it were, with this thread my good growing friend, Don Vitko, reminded me that he had given me several potted seedlings of (supposedly) Micranthocereus auri-azureus that he had grown from seed last year. Here is a pic of them I took yesterday afternoon:

[RICHAUD]

Here is my Micranthocereus polyanthus ( plant from Cactusflower in Belgium bought at the ELK)

Micranthocereus polyanthus.jpg (50.03 KiB) Viewed 2902 times

[James Pickering]

As promised, Micranthocereus polyanthus ssp. alvinii:




..... at least that is what they are supposed to be. After researching on the web, there seems to frequently be some confusion with nomenclature and attribution. The plants Depicted here are about two years old from seed - I forget when they were planted (my memory - and record keeping - is pretty bad these days). Pics taken yesterday afternoon.

James

Marlon (Machado) appears to have some misgivings about this nomenclature. Check out his comments here:

http://www.iucnredlist.org/details/40908/0

I anticipated flowers with some “pinkish” coloration rather than flaviflorus orange/yellow.

[James Pickering]

Here is my Micranthocereus polyanthus ( plant from Cactusflower in Belgium bought at the ELK)

Micranthocereus polyanthus.jpg

Mine are descendants (via cuttings) of plants that I originally grew from seed that I got from Gil Tegelberg in the early 1960s. It is the first Micranthocereus (Cephalocereus back then) that I cultivated.

[James Pickering]

Pic of Micranthocereus polyanthus ssp. alvinii (with Arrojadoa dinae and Pereskia portulacifolia) in the entranceway to my house - pic taken this morning at 10am.