Well, that door remains open.

I have been updating a few Mammillaria entries in the database and have tagged a number of plants with cryptocarpic fruit. This is by no means a complete list (and please suggest additions or make changes as you see fit)...

https://garden.org/plants/sear...

In case that term is new for you, it refers to fruit which matures within the stem, rather than being extruded from it, usually in a club-shaped form, like other Mammillarias. This reproductive feature is characteristic of the Longiflorae, a handful of Mammillarias which tend to be small, with tuberous roots and big flowers. There's a very informative blurb on the subject here (see bottom right):

http://www.cactus-art.biz/sche...

There are some interesting consequences of cryptocarpic fruit related to seed collection and germination.

Some of the members of this group have very attractive spines (like hernandezii). The database has some good flower pictures for a bunch of these plants, which are generally reputed to be difficult (rot-prone and demanding about strong light) in cultivation.

Can you tell if a plant has cryptocarpic fruit? Is it visible from the outside of the cactus? Doesn't sound like it would be easily apparent. Also sounds like an extreme form of seed protection which could easily backfire for the plant. The seeds not only have germination inhibitors, but seem to require age measured in years for a high percentage of germination. Bad combination if the habitat undergoes an unfriendly change. Might make for a precarious existence in a population.

Two of the M. rhodantha fruits were drying up. I pulled them off and looked inside. There were no seeds, so the deflated balloon appearance was an accurate reflection. The remaining two look the same, so it's probably not making any seeds. For a week or two though, the fruits are as colorful as the blooms

needrain said:Can you tell if a plant has cryptocarpic fruit? Is it visible from the outside of the cactus?

Apparently it may bulge outward on some plants, and there's a membrane which breaks open to release the seeds little by little. So you might see bulges in the axils or little holes with seeds spilling out of them. There's an interesting picture here:

http://llifle.eu/Encyclopedia/...

I don't really see any advantage for cryptocarpic fruit. Having long-lasting seed may be an advantage in a setting where rain is limiting, and there's only enough rain for germination every few years. But I suspect these plants pay a big price in dispersal. A few of them are threatened, vulnerable or endangered.

"..don't really see any advantage for cryptocarpic fruit." When a plant develops adaptive behavior, there is almost always an advantage to having the adaptation - at least for the time it was developed. It may be an historical adaptation that is no longer beneficial but at one time it was almost guaranteed to have been advantageous. If it hadn't been, then some other means would have taken place or it would have become extinct. That's my thinking. I wonder if those setting cryptocarpic fruit had some common environmental factors specific to them. Answers for these things may be lost in the depths of time.

Just because I don't see something doesn't mean it doesn't exist. I agree completely with you.

I wonder how many cryptocarpic cacti there are? That's really a curious means of protecting the seeds. Are they all Mammillarias? Do they all have a common ancestor, I wonder? If other plants outside of cacti developed the same trait, then I'd think it would have been a response to environmental pressure. To me, it would indicate a long period of time, though it might be limited geographically. Cataclysmic events don't give life forms much of a chance to adapt.

Outside the Mammillarias, I only know of one cactus, which was apparently named for this feature.

Yavi Cactus (Yavia cryptocarpa)

Guess y'all might be getting tired of seeing photos of my Mammillaria Karwinskiana subsp nejapensis, but I was able to get the best photo I've managed of the buds and blooms, so here's yet another photo. Lucky it's sort of naturally photogenic, I think

No flowers on my M. spinosissima 'Un Pico', but it has grown big enough to warrant its own large hanging basket. The head in front is not 'Un Pico' but two of the smaller heads in the back still are...

so got this little plant earlier in the year


due to space pressure i needed to move the plant to a filtered window . It has grow but i think the plant is stretching out? also the spines have lost colour.


Do you all this this is a lack of light? Anyone hazard a guess at an ID
Steve

Yes, it is definitely starting to show a low light habit. It is not showing full on light starvation but definitely you can see that the body is stretching and the spines are starting to 'weaken', especially the central spines are less prominent.

More light, if possible, but unless the plant goes in full on stretch mode it could be OK for a while longer in these conditions... but if it goes super stretchy it is going to be irreversible so do not wait too long to give it better light.

@ mcvansoest
thanks for the comfirmation. Sometimes we need telling what we already can see!

Steve

My 'Ginsa Maru' has a bud on it. A rather odd time of the year for me, but I'll take it.

It opened today:

One of my favorites: Mammillaria bocasana multilanata with fall flowers


An impulse buy from the local supermarket today. Its labeled Mammillaria elongata montrose. I'm torn about whether that ID is accurate or not. It seems to me it should be a little more golden.

What does the "multilanata" mean?

Lanata in Latin means woolly. Lots of woolliness? Its a cultivator of M. bocasana so maybe its the furry off-spring?

DaisyI said:An impulse buy from the local supermarket today. Its labeled Mammillaria elongata montrose. I'm torn about whether that ID is accurate or not. It seems to me it should be a little more golden.

When we were in north-central Mexico (which is where M. elongata is from) we saw a bunch of different versions in botanical gardens... mostly straw colored spines.



There are variations in cultivation which stray pretty far from that. Pilbeam says "in cultivation the variation in spine color of both subspecies is legion". "Copper King" is golden brown. I have a red-spined (and red-flowered) version which may have some hybrid blood.



I do like the white-spined version, monstrose or not.

Thanks Baja. Nice photos too. That red flowered elongata is very nice.

A photo here with decent resolution showing buds, spines, bristles, wool, and fuzz (and their respective origins in the axils or on the tips of the tubercles).



And another perspective showing successive years of growth on the stem, evidenced by alternating wooly and non-wooly periods.