Echinoagave, Paleoagave, Paraagave, oh my

As Bob Dylan once said, “There is nothing so stable as change.” That’s true for a lot of things, but especially for taxonomy. Many people hate it when the botanical names they’ve painstakingly learned become something else. Others embrace it as a corollary of progress. Me, I’m OK with it as long as there’s a good reason.

A big brouhaha ensued when in 2014 five new genera were split off the genus Aloe: Aloiampelos, Aloidendron, Aristaloe, Gonialoe, and Kumara. This wasn’t some random flight of fancy, but the result of molecular studies that shed new light on the evolutionary origin of what we call aloes.

Now something similar is happening to agaves, although on a smaller scale. A couple of months ago (January 2024), a team of Mexican botanists published an article titled “New Genera and New Combinations in Agavaceae” in which they propose three new genera based on genetics, morphology, and the estimated time they diverged from the common ancestor of all agaves.

I know, this is stuff that makes your eyes glaze over, but it helps us better understand how agaves evolved and how closely related they are to each other. Humans want to bring order to the chaos of nature, and this is another small step in that direction. I won’t go into greater technical detail here, but if you’re interested, you can download the article from here. Unlike many other scientific articles, this one is free, i.e. not behind a paywall.

The vast majority of agaves will still be in the genus Agave – at least for now. Below are the three new genera and the species they contain:


“Echino-” comes from the Greek word echînos (hedgehog) and means “spiny.” This new genus diverged from the genus Agave approximately 4.15 million years ago. It includes compact hedgehog-like species that are polycarpic, i.e. don’t die after flowering.

As proposed by the authors, the genus Echinoagave consists of these species:

  1. Echinoagave albopilosa
  2. Echinoagave cryptica
  3. Echinoagave cremnophila
  4. Echinoagave dasylirioides
  5. Echinoagave gracielae
  6. Echinoagave kavandivi
  7. Echinoagave lexii
  8. Echinoagave petrophila
  9. Echinoagave rzedowskiana
  10. Echinoagave striata
  11. Echinoagave stricta
  12. Echinoagave tenuifolia

Of these 12 species, only three are reasonably common in cultivation: Echinoagave albopilosa and the two closely related Echinoagave striata and Echinoagave stricta.

Echinoagave albopilosa

Echinoagave striata

Echinoagave stricta


“Paleo-” comes from the Greek word palaios (ancient) and means, well, “ancient.” This new genus is the earliest to diverge from the genus Agave, approximately 6.18 million years ago. It includes species with unarmed, soft, curling leaves.

As proposed by the authors, Paleoagave has only one species:

  1. Paleoagave bracteosa

Commonly known as the squid agave, Paleoagave bracteosa is a popular landscaping plant because (a) it’s almost completely unarmed and (b) it’s cold-hardy to 10°F. According to Loree ‘danger garden’ Bohl, it made it through Portland’s record-breaking winter unscathed.

Paleoagave bracteosa

Paleoagave bracteosa flowers


“Para-” comes from the Greek word pará (akin to) and means “closely related.” This new genus diverged from the genus Agave approximately 4.25 million years ago. The species in this genus have larger rosettes with a small number of large non-curling leaves whose margins are either toothless or sport only a few sparse teeth.

As proposed by the authors, Paraagave has only one species:

  1. Paraagave ellemeetiana

Paraagave ellemeetiana resembles Agave attenuata, but has fewer leaves. Both species are tender, which is why they’re not typically used as landscape plants in Northern California where I live. On the other hand, in Southern California, Agave attenuata is the most popular agave for landscaping, and Paraagave ellemeetiana is occasionally seen as well.

Paraagave ellemeetiana

There you have it, a few new names to learn, especially if you want to impress (or annoy) fellow plant nerds. In horticulture, nothing will change in the short term. In fact, I’m sure that even in five years, nurseries will still use the old names.

😉 In a recent blog post, Tony Avent, the founder of Plant Delights Nursery, wondered out loud what to call hybrids involving these newly named agaves (like Paleoagave bracteosa × Agave lophantha) and made several tongue-in-cheek suggestions like ×Closetoagave, ×Sortofanagave, and ×Notquiteanagave.

© Gerhard Bock, 2024. All rights reserved. To receive all new posts by email, please subscribe here.


  1. Your post is a great introduction to what I'm guessing may become a widely accepted split once other botanists dig into the work presented in the January 2024 article. I wonder how the xMangaves will be treated when all the dialogue on the Agave genus shakes out?

    Thanks for sharing the photo of the squid agave flowers - that's the first time I've seen them.

    1. Bracteosa flowers are something else! I've had one in the backyard for 10+ years, almost full shade. No sign of flowering, but I look forward to the day.

  2. It suppose it makes sense to group the agaves that don't die after flowering on their own (on a side note I wish I could keep Echinoagave stricta and striata straight. I think one of them is hardier than the other). Now to try to remember to say (and type) Paleoagave bracteosa...

    1. Stricta vs. striata, I can't tell them apart either. I think stricta forms tighter hedgehog shapes. San Marcos says 20-25°F for stricta vs. 0-10°F for striata.

  3. One rare or maybe unique instance when I can (sort of) agree with Tony Avent. DNA research is changing a whole lot of things now, and more every day.

    1. As DNA analysis becomes more affordable for research institutions, I expect to see more taxonomic changes across the entire plant worlds.

  4. This stuff makes my eyes light up, not glaze over. I love learning how things are related to each other. The biggest surprise was seeing that Polianthes in the mix, and then seeing that Polianthes and Manfreda are more closely related to Agaves than to the Echinoagaves. Really cool stuff. I never, ever would have thought Polianthes was a close relative to Agave. At least this set of changes makes sense to me and is easy to adopt. Easier than some of the Berberis/Mahonia and Hebe/Veronica research, anyway. My mind is more resistant to some changes than others.

    1. Hans Hansen of Walters Garden created a trigeneric cross between a Polianthes, a Manfreda, and an Agave. It's sold under the name xHansara 'Jumping Jack'. Unfortunately, it didn't inherit the wonderful tuberose fragrance.

      Berberis/Mahonia, that one isn't 100% resolved, is it?

    2. I don't think so. But the paper I just read by Hsieh et al. 2022 (Mahonia vs. Berberis Unloaded: at did show that Mahonia and Berberis are genetically distinct and presented very good arguments for why they should be maintained separately. It all lies with some very arbitrary decisions on where to draw the line and people's conclusions can change, depending upon which data people are using. Apparently some of the earlier papers that tried to lump Mahonia into Berberis were working with a limited number of species, and it also depends on which part of the genome the taxonomists are looking at. Cool stuff, IMO.

  5. Yikes! just when I am starting to learn the name so of and recognize different agaves they go and change the rules again. Drives me crazy especially as all the new names tend to be harder to pronounce.

    1. LOL, new names keep us on our toes. But some names are simply impossible. The Mexican flame vine used to be Senecio confusus. Easy to remember, right? Then they moved it to a new genus, and now it's called Pseudogynoxys chenopodioides. Try to memorize that!


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