Coleocephalocereus???

[scubagirl]

Hi all,
Just wondering what kind of cactus this is. I've had it for around 20 years and got it in southeast Idaho. It's never flowered. Based on the pictures on the website, it looks like it might be some sort of Coleocephalocereus - I'd love to know for sure!

2014-10-02 19.49.52.jpg (17.04 KiB) Viewed 466 times

2014-09-28 16.20.24.jpg (31.1 KiB) Viewed 466 times

[Astro]

Possibly Marginatocereus (the 'spiny form' (juvenile?)). Doesn't look like a Coleo to me (the spines are not right); it's a genus you're less likely to come across by accident.

[scubagirl]

Are you referring to this one? Yes, that could be it, too. All the pictures of those have fewer ribs than mine, though.