Mammillaria?

[gillinger]

It looks like a Mammillaria, with spines on the end of the tubercles, but I can't pin it down at all. Any suggestions greatly appreciated.
Thanks

[anttisepp]

Coryphantha radians, aff, IMHO

[gillinger]

Thanks, anttisepp, I'm not even in the ballpark, am I? Just can't seem to get a handle on this identification lark, so hats off to you for this.

[metsolt]

Thanks, anttisepp, I'm not even in the ballpark, am I? Just can't seem to get a handle on this identification lark, so hats off to you for this.

You're not really too far with this one. Tubercles do mean Mammillaria, but related genera can be recognized by the groves on their tubercles. Those are Coryphantha and Escobaria. I believe in the past they were referred to as Mammillaria as well.
Once you get to notice those characteristic things like groves in this case, you're gonna be sure it's one of the two genera and not a Mamm.
It's just gonna take some time for it to come naturally.

[Glorioustache]

How do you guys distinguish C. cornifera from C. compacta when juvenile?

[gillinger]

Thanks, anttisepp, I'm not even in the ballpark, am I? Just can't seem to get a handle on this identification lark, so hats off to you for this.

You're not really too far with this one. Tubercles do mean Mammillaria, but related genera can be recognized by the groves on their tubercles. Those are Coryphantha and Escobaria. I believe in the past they were referred to as Mammillaria as well.
Once you get to notice those characteristic things like groves in this case, you're gonna be sure it's one of the two genera and not a Mamm.
It's just gonna take some time for it to come naturally.

The main problem with identification of any plant, for me, is that there are so many variations within a specific genera and photographs can show only full grown plants when I'm looking for matching what is practically a baby. F. glaucescens springs to mind. I check the photos on this site as well as Liffle but even when I'm sure of what I've got they sometimes still don't look the same! As I said earlier, hats off to anyone who can identify the photos posted on here. You all do a splendid job

[DaveW]

Not only are there variations within a genus, the same applies to species. In habitat you get variation within a population where two plants growing side by side can look significantly different, just like two humans even though related. Also plants growing in different populations even though the same species can vary population to population.

What constitutes a species then can simply be a matter of where you draw the line and consider a variation is distinct enough to warrant another name even at subspecific level. Add to that many species in cultivation are really selected clones picked because they looked the best rather than being representative of the variation found in the wild. Therefore when new material is imported from habitat many will not believe it is the same species simply because they have got used to the "cultivated standard form" for that species.

Nature does not have to fit in man's convenient little boxes regarding speciation or classification, plus its also constantly ev0lving.

[metsolt]

Not only are there variations within a genus, the same applies to species. In habitat you get variation within a population where two plants growing side by side can look significantly different, just like two humans even though related. Also plants growing in different populations even though the same species can vary population to population.

What constitutes a species then can simply be a matter of where you draw the line and consider a variation is distinct enough to warrant another name even at subspecific level. Add to that many species in cultivation are really selected clones picked because they looked the best rather than being representative of the variation found in the wild. Therefore when new material is imported from habitat many will not believe it is the same species simply because they have got used to the "cultivated standard form" for that species.

Nature does not have to fit in man's convenient little boxes regarding speciation or classification, plus its also constantly ev0lving.

I agree.
There are great variations within official species. I recently tried to ID a cutting I got. Apparently, it's from an Echinocereus scheeri, but when started researching it, I got so confused... So many flower colors, so many spine shapes, lengths, I'd never see all those quite different plants as members of the same species, but it officially is.

Thanks, anttisepp, I'm not even in the ballpark, am I? Just can't seem to get a handle on this identification lark, so hats off to you for this.

You're not really too far with this one. Tubercles do mean Mammillaria, but related genera can be recognized by the groves on their tubercles. Those are Coryphantha and Escobaria. I believe in the past they were referred to as Mammillaria as well.
Once you get to notice those characteristic things like groves in this case, you're gonna be sure it's one of the two genera and not a Mamm.
It's just gonna take some time for it to come naturally.

The main problem with identification of any plant, for me, is that there are so many variations within a specific genera and photographs can show only full grown plants when I'm looking for matching what is practically a baby. F. glaucescens springs to mind. I check the photos on this site as well as Liffle but even when I'm sure of what I've got they sometimes still don't look the same! As I said earlier, hats off to anyone who can identify the photos posted on here. You all do a splendid job

I also understand your frustration with young plant ID. Often it's hard to even hard to have a precise ID on grown plants without flowers, and jouvenile plants are a whole another story. Most often they're of some common species so it's relatively easy, but with not-that-common species it gets tricky.

[DaveW]

In some species plants form clines where the features at one end of the line gradually clanged along the length of their distribution. Some regard these as a single species and others may split them up into more than one, but it is difficult as the transition is gradual. The problem in the past is various plant collectors may have stumbled across this cline at various places in the past and not knowing of the gradual transition named them different species. Only when the full extent of the cline was known could a sensible decision as to species be made and unwanted names reduced to synonymy. The problem of course being that the first named plant from that cline would take priority and that form may not be typical of the species as a whole just being an outlier

"cline
a character gradient over a geographical area where one or several morphological features gradually change over a part or over the whole distribution area."