I have noticed this like formation on one of my Yellow Xenox, which is doing well otherwise (bought from a local dealer).
That is the only stalk I have seen it yet, almost appears to be in 2 places on that stalk, but mainly in 1 area.

I was thinking it is a disease by looking at a video with Dick Wright "Dick Wright on Echeverias 3: How to Grow" on Youtube, they mentioned mycoplasma.
Sure looks like what they show in a second picture at min 6:31
I cannot post links, othwerwise I would have posted the link with the video at that exact minute.

What do you think? Maybe some people have more experience with diseases on succulents.
At least so far I am convinced it is what they show in that video.

Hi Paleo, great photos.
Maybe @JungleShadows can help.

They talk about horses in that video I mentioned when the mycoplasma is, coincidence is that at this nursery they also have horses around there. Not sure if that matters, just mentioning.

If you use an "@" on the forum, it's like on instagram where the user talked about gets a notification?

Yes it notifies the person.
Let me try @GregC and @zuzu

I'm wondering if that is not some kind of damage from handling, and it has healed over?

Does not look like insect damage.

You called, Lynn? I don't have a clue as to what it could be.

I was also thinking it was mechanical damage and not a problem, but I sure could be wrong.

Thank you for coming Zuzu. I couldn't think of who might be the go to person of diseases in plants? I thought you might know?

That is what it looks like to me also Karen. I have never had disease or pest problems with my sedum so have no experience in that direction.

This is the photo from that video, I thought it looks so much like this diseased echeveria, which is attacked by a bacteria, mycoplasma, at least that is what they mention.

Oh my. Watch your sedum to see if this progresses. And keep them away from all of your other plants.

Yes, that is scary looking. I hope it's not what you have on your plant. I've never come across this before.

I am very concerned about this matter, checking that clump i see the same thing on another 2 stems, maybe it was already there but I did not notice before. Plant is "isolated" now, I will monitor it for a month, which I am not sure how good of an idea is, maybe it is better to burn it already.

Please keep us updated on how it progresses.

I took the liberty of sending the photo to our state plant pathologist for ideas. I'll reply when I hear back from her. The great thing about working for the Dept. of Agriculture are the resources available.

Wow!!! Greg that is awesome.
I look forward to hearing what she has to say about Paleo's plants.

From the Plant Pathologist: From my research I'm struggling to find any mycoplasma-like organisms that affect sedum showing those symptoms. There are a couple that describe proliferation of the plant, reddening/yellowing of the plant (unnamed phytoplama), stunting, twisted flowers (Spiroplasma citri). Did they have any more specifics than just that? I reached out to a listserve of plant diagnosticians and am coming up empty so far.

That's great GregC, that you could reach some knowledgeable people, I appreciate that.
I was basing my wording, I mean "mycoplasma", based on what I was hearing in that dick wright video with that echeveria photo, which is from that video. Maybe they are using wrong terms to describe the issue of that cracked surface.
So far that plant has no redding/yellowing, stunting as for flowers there are no flowers yet at all, it seems all good except I've that cracking of the surface on certain spots on 3 stems.

What could that be on the plant, it is non-pathogenic maybe?

If it is from just mechanical damage it could be like a callous formed to cover the damaged area.

Does anyone know what could these be on my Hylotelephium spectabile?