Trichocereus peruvianus var. knuthianus

[M S Smith]

This should spark some interest...I was digging through some things and came across the label that came from NMCR with my Trichocereus peruvianus var. knuthianus, and what do you know, it say..."SD from Australia." I'm going to assume the "SD" means seed. For the longest time I thought my plant was a T. chiloensis, but I think the ID as knuthianus is probably right. It is quite a slow grower that's for sure, but then again, I've had it incredibly root bound for years.

For comparison this second shot is of Sacred Succulents T. knuthianus...

~Michael~

[Evil Genius]

Hi Michael, well thats really a tricky one and if i wouldnt know better from what you just wrote, i´d say its a Chiloensis too. It looks totally unlike the plant i grow as Trichocereus Knuthianus. I assume you didnt have any pups yet, right? bye EG

[Bretloth]

Here's the Knuthianus we have down under, pretty sure it's from Ritter seed, will have to double check. Doesn't look like what you have there Michael, the second pic maybe a hybrid? The SS03 you guys have over there looks to be Knuthianus.

Edited December 9, 2011 by Bretloth

[bit]

The local nursery has this as Chiloensis... what do the rest of you guys think? Note the curved spines...

Edited December 9, 2011 by bit

[Evil Genius]

HI Bit, very nice pics. Thanks for sharing. Do you have a closeup of the spinebases? My first guess would indeed be Trichocereus Chilensis but i´d do the same with the plant in Michaels Pic so i´d really love to see a few more pics if available. Also it would be great to see the base of the plant. Knuthianus developes a rounded stem, almost like a tree with age. bye Eg

[solomon]

^^^^ I looove CC's T. chiolensis

here is some more pics of the plant Bit posted above on their website

[Bretloth]

I know Horst Kuenzler at NMCR got alot of stuff from Fields down here, traded alot together. Here's some pics of the Chiloensis out there, looks alot like the 1st pic. Especially the spination. Awesome cactus

[Ambient]

Here's the Knuthianus we have down under, pretty sure it's from Ritter seed, will have to double check. Doesn't look like what you have there Michael, the second pic maybe a hybrid? The SS03 you guys have over there looks to be Knuthianus.

 

I've some cuttings just like those, they were sold as Peruvianus, but I suspect otherwise. I'll post pics when the sun is up.

Edit: Pics

I'll be intrigued to see which is the real Knuthianus, or weather they are just a different variety of the same.

Edited December 10, 2011 by Ambient Forest

[cactuscarl]

The chiloensis is a hard one to ID i have two forms that look totally different. You can tell they are both chiloensis but they are totally different thickness and even shape one has big curved branches and is rather tree like the other is thin shorter spines and climbs

[ballzac]

knuthianus IDs have always confused/fascinated me. The type of knuthianus in the OP has spination very similar to a cuzcoensis. In fact the SS one looks like a typical cuzcoensis to me. Then there are the ones like that posted by bretloth. The spination is much more like a long-spined pachanoi or short spined peruvianus.

So, lets say they're both descended from (or a subspecies of) peruvianus. The question is, are they descended from the form with similar spination, respectively, and then have evolved convergently to have the knobbly rib structure? Or are they both descended from an ancestor with knobbly rib structure and each has evolved convergently towards the forms with similar spination. For some reason the former seems more likely to me, and if this is the case, then they could be quite different genetically, even different species.

I have trouble with IDing knuthianus since there seem to be intermediate forms that display the knobbliness to varying degrees, and there seems to be a fair amount of confusion amongst the ethnobotany community at large, so I like to keep an eye on threads like this.