Looks like Hechtia argentea. See photo at http://fcbs.org/pictures.htm

here is a link from Kew Gardens
http://www.cambridge2000.com/gallery/images/PA309696e.jpg

If it was actually collected in Argentina, that probably rules out Hechtia. The natural distribution of the genus Hechtia is limited to Central America, Mexico, and the Big Bend area of Texas. It's far more likely that it is a Dyckia, although it may be tough to get a positive ID without the inflorescence/ flowers.
Chanin is your best hope of getting an ID based on the leaves alone!
Paul

Hi Spiney friends and yes Paul, I'm quite familiar with this type of leaves form,
this should be a species in genus Deuterocohnia, may be Deut. longipetala
or Deut. meziana which have been offered in EU for decades.
Among xeric broms, the blooming from the plant's apical is Deuterocohnia's characteristic
which rarely occur in Dyckia.

Markeee,
I believe Stephania has the ID correct. But with FCBS lacking a full plant photo of Deut.longipetala,I will post a pic of mine to help with the ID between meziana and longipetala,and you can decide which one best matches your plant.There's a good photo of Deut. meziana on the fcbs.
Bob

Deut.longipetala:
{{gwi:505711}}

Thanks very much for all the help. I can take a photograph of the infloresence if that will help further nail it down. However, it has finished flowering.
This plant was an absolute bargain at £6.50 (about $12us).

Regards,

Mark

Hi Mark, just noticed that you had mentioned the plant came from Argentina

I came across with this text in the 'Bromeliads' by Victoria Padilla :

"... In northwestern Agentina, in the province of Salta, two species,
D.haumanii and D.longipetala, can be seen covering the mountains
on either side of the highway for miles, constituting almost the entire vegetation.

When seen without its inflorescence, a member of this genus might easily
be mistaken for Puya, because ot its rosette of stiff, heavily pined leaves.

When in flower, however the distingtion is immediately obvious.
Whereas the spike of the genus Puya consists of a dense head of flowers,
the inflorescence of the genus Deuterocohnia is loosely branched and is lateral..

The flowers, too, are small and usually inconspicuous..."

In your case, the flowers should be yellow-green with long tubular looking.

Mark,
If you could post a photo of the inflorescence,I think it would be helpful to nail down an ID.
That center bloom spike in your photo,as does the plant's leaves, looks a lot like the photo on fcbs,of Deut..meziana. And if the plant is meziana,the bloom stalk will continue to re-flower over the next 6-8 years.A unique characteristic of Deut.meziana.
Do you recall the color of the flowers when it was in full bloom,and were they small or elongated?
Bob

Thanks, Stephania/Bob. Unfortunately, I didn't get to see the flowers as I only bought this plant on Tuesday and it had finished flowering. I will post a photo tomorrow morning.

I agree that it does look like Deut meziana.

It was definitely collected in Argentina by a well respected UK nurseryman, Bob Brown of Cotswold Garden Flowers.

Mark

Mark,
According to V.Padilla's book,Deut.meziana is native to
the Matto Grosso of Brazil,where it grows on sunbaked rocks.
Checking a map,the Matto Grosso is about 300 kilometers away from northern Argentina,(seperated by Paraguay.),so maybe its a possibility that it made the trip into Argentina. ?
Looking forward to seeing what the inflorescence shape is like.
Bob

Due to its locality, I think this should be Deut. longipetala, this species has many forms.
And if it might be D. meziana you will find its unique characteristic,
in that the inflorescence continue to bloom from the same scape for many years!
So don't cut that flower stem,(^_^)

Here's the finished infloresence...

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Form the pictures, I'm quite sure that yours is Deuterocohnia longipetala
Please take a look at Charlie's Web.

Here is a link that might be useful: Deuterocohnia longipetala