Cotyledon ID help? green-bean leaves, orangish-red bell-form flowers

[amanzed]

Hi! Could you help me identify this Cotyledon sp.? Is it just another form of C. orbiculata?

I bought it from a big-box store a couple years ago, probably distributed by Altman's. I believe it was identified merely as Succulent sp. When I first picked it up (being even less experienced back then), I mistook it for a Senecio sp. I have grown and divided the original 3" plant into three sizable 8" plants. (In the picture, they look a little leggy and haggard after blooming. I plan to take cuttings and propagate them on).

Thin, finger-shaped leaves are light green and resemble home-grown string beans, but circular in cross-section. They are matte and mildly glaucous -- not as waxy-powdery as some C. orbiculata (pig's ear, esp. var. "powdered sugar"), but not nude-glossy green like typical var macrantha.

Stems show typical Cotyledon bumps from old leaves (these plants also seem to show a rust-colored reaction to some pest... help?). New leaves start as tiny, dark-pink tongues -- also typical of Cotyledon (cf C. orbiculata).

Flowers look the same as Cotyledon orbiculata (to my hobby-grower eyes): orangish-red bells from a tall stalk (2' stalk on an 8" plant). I grow at least 5 forms of Cotyledon orbiculata, and this plant flowered around the same time.

The pleasure of the plant is the slightly irregular surface of the green "fingers" -- not smooth like Senecio madraliscae "blue chalk fingers". These chunky leaves pile up into improvised formations, on some days resembling a Balinese statue with dozens of arms.

Not to mention the ease of culture and propagation. And the apparent "convergent evolution" of morphotype with Dudleya hassei, Senecio madraliscae, and countless Mesembryanthemaceae -- just to name a few.

Also the flowers attract hummingbirds.

--DCE
sentientmeat.net

Attached photo is compressed for XericWorld.com. For full resolution at Flickr, click here.

[Tim Harvey]

Could be the digitate form of orbiculata, but it seems a bit tall and leggy. There are numerous leaf forms of this species. I saw an article on them recently (CSSA Journal??) but don't recall exactly.

T

[amanzed]

Hi Tim,

Thanks for your input. Yes indeed, I've been suspecting it might very well fit in the highly variable C. orbiculata taxon. I will look for that article you mention.

This Cotyledon is a humble and easy plant, but it has caught the eye of my husband (who thought they looked like many-armed deities) and other friends -- people who don't share my plant obsession.

I'm interested in the ways certain succulents show charisma even for non-aficionados... I want to learn more about this aesthetic response and how to harness it.

--DCE
sentientmeat.net

PS The color balance is a little off in the phone snapshot -- these plants are string-bean green with a bit of red at the tapered leaf tips, not the slightly bluish green in the photo. (I realize such niceties will not cast it in or out of orbiculata.)

[amanzed]

I think I found it. It matches the description of Cotyledon orbiculata ssp flanaganii. Most characteristically, my mystery plant appears to have leaves arranged in whorls of 3 rather than opposing pairs (2). I hadn't noticed before, but this is one of the primary distinguishing characteristics of ssp flanaganii.

Incidentally, C. o. v. flanaganii seems to occur in a rather restricted range in South Africa (especially compared with other forms such as C. o. v. orbiculata). And it is the only C. o. variation listed as under some environmental threat.

On a tangent, I noticed this plant just a few days ago in coir-pot succulent assortments distributed by Altman's (I believe) for sale at Home Depot. So C. o. v. flanaganii (if I'm correct) is well established for now in the trade.

I will add a reference to an excellent paper from 2005 (free to download!) and a terrific (but not free) paper from 2009. I have to look up a lot of words, but doctoral work in the completely unrelated field of mathematical logic taught me not to give up... if you slowly keep reading (and look up the bits you don't know), you might be able to figure it out.

--dean
sentientmeat.net

[Xanthoria]

Looks a lot like a plant I have which I think is C. orbiculata var. oblongata

http://pennsylvaniagarden.blogspot.c...ulata-var.html

We have two types - one is much more glaucous than the other. Neither were labeled when we got them.

[Andy]

I have a plant that looks nearly identical. Other than the emerging leaves being in pairs, I wouldn't be able to tell if they were paired or whorled once the leaves are mature. A year or two ago I gathered seed from my plant and they have come up with a wide range of leaf shapes...so with that I assume mine is a hybrid. I didn't have any other Cotyledon plants at the time and I doubt any of my neighbors have any so I don't think the hummingbirds and bees created a hybrid.
-andy