peterb's 2012

[iann]

why they were separated out into their own genus (Neobesseya).

Deciduous flower remains? Strongly embedded growth habit?

Or the genetic differences that Crozier reported, albeit with selected samples that almost guaranteed segregation? It might be interesting to consider the close relationship shown between C. macromeris and Neobesseya (E. missouriensis and E. robinsorum in this sample) while C. sulcata and E. tuberculosa are separated with some Mammillarias and Pelecyphoras respectively. From these five sampled species, the genus Coryphantha appears to be a completely unnatural grouping.

[peterb]

I was just going on gut instinct, looking at how very different the seeds and seedlings of missouriensis are from, say, guadalupensis or the whole sneedii group. I wasn't aware of the more detailed, botanical differences you mention and I haven't read the Crozier. But it has long seemed to me that Coryphantha is just a big old pile of polyphyly, for convenience's sake.

peterb

[peterb]

Echinocactus polycephalus seeding, a few years old, the form from Resting Springs. Straight juvenile spines. This one has been slow to thrive here.

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Echinocactus polycephalus from Inyo County, finally starting to do better after a rough first few years, for some reason.

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Pedio winkleri RP132.

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A few pics from yesterday.

[RichR]

I was just going on gut instinct, looking at how very different the seeds and seedlings of missouriensis are from, say, guadalupensis or the whole sneedii group. I wasn't aware of the more detailed, botanical differences you mention and I haven't read the Crozier. But it has long seemed to me that Coryphantha is just a big old pile of polyphyly, for convenience's sake.

peterb

I wish I had studied botany formally. I still don't understand the criteria that are used to separate cacti into genera, species, and varieties (or subspecies if you wish). Sometimes the distinguishing characters that separate species seem more like varietal differences to me and vice versa. Heck, they can't even get the genera sorted out.

For instance, Big Bend National Park's official master plant list still has all the Escobarias in the park listed as coryphanthas. All very confusing for a cactus-lover who is trying to learn the family on his own.

[peterb]

I'm not sure the formal study of botany helps in understanding the decisions of cactus taxonomists, although it is helpful to understand flower anatomy, descriptive vocabulary and flower morphology. I think it is even more helpful to understand the taxonomical philosophy/perspective. The real problem (but also the wonderful flexibility of it) is the lack of a formal, guiding definition for the species level of taxonomy. The botanical definition of species has necessarily been much more open to interpretation than the zoological one. (Not that taxonomists in zoology don't differ...I'm told herpetology is a bloodied battleground of raging controversy, for example).

At the genus level, a lot of opinion gets thrown around also. The goal has always been to form "natural groups" of clearly related plants. Relatively recently, the goal has become even more ambitious: to delineate clearly monophyletic groups at the generic level. That is, groups that can be proven using genetic research to have had a single common ancestor. This whole area actually has very little to do with botany per se.

Anyway, I don't really have an issue with it anymore. I use whatever names I want, while respecting the idea that there are historical names and currently accepted names. I prefer Escobaria for the distinct group because it keeps things clearer for me personally. But I can hang with anyone, including Weniger, who went to mega-genera and used "Mammillaria" for everything with tubercles.

peterb

[iann]

Coryphantha is still in common usage in the US. The use of Escobaria for those little spiny things we know and love was coined fairly recently by an Englishman and has caught on much more on this side of the Atlantic. Ultimately, both names are under threat because they are all tangled up on the fringes of Mammillaria.

I don't know where the "Inyo co" E. polycephalus are from but isn't Resting Springs in Inyo co? I feel comfortable with mine when they develop a blue tinge that I've come to associate with being well ripened

[peterb]

Yes, I don't know about those Inyo polycephalus either. MG has them as this: 176.9-polycephalus Inyo Co, CA, super hot and hostile habitat

peterb

[iann]

Yes, I don't know about those Inyo polycephalus either. MG has them as this: 176.9-polycephalus Inyo Co, CA, super hot and hostile habitat

peterb

I have the same one.

[peterb]

Nice! Yours clearly thriving in the super hot and hostile habitat of the UK.

peterb

[peterb]

The first flower of the season opened yesterday, on Echinocereus viridiflorus davisii. Usually it's a Pediocactus to kick things off.

Some seedling pics first. I keep forgetting that the new uploader puts things up in reverse order.

peterb

[majcka]

Niiiceee! All of them.

[billdee]

Everything looks great! I really want to start growing from seed too, but I have my hands full for now, but maybe next year I'll give it a try.

[RichR]

Wow, your tray is loaded with seedlings! Looks like a high germination rate in a short time.

Love the colors of The E. davisii. Mine had one little bloom last week, but now has about eight new buds.

[Arjen]

beautiful flower on that davisii!

[peterb]

Every time I sow, I push the moisture and humidity at least a little bit too far. Yesterday was about 2 or 3 days past when the dome lid should have been propped up. The leading edge rotting species are always Astrophytum capricorne and Echinomastus erectocentrus or johnsonii for me. The pot of Echinomastus erectocentrus acunensis from Sonoyta, Sonora had a couple of damped off seedlings. So I completely switched stuff up, got a bunch of possible problem pots out ino some air all day today, propped open the dome and I'm starting to let some stuff dry out. One problem with the mineral mix using the Napa oil dry that I can see is the surface dries out nicely but the mix remains moist below. This is actually very good, but it led me to think the pots were drying, when in fact there was still moisture under there. It's funny how just switching from Schultz Aquatic Plant Soil to Napa changed things up a bit. They are both high fired clay, but the small white granules of Napa are lighter and dry out more visibly on the surface.

Some pics: