identification please

[wimmie]

Hello Palmtalkers; what do you all think: is this a Cycas rumphi or is it circinalis? The leaflets are quite wide/luxurious.

Thanks!

[happypalms]

What a lovely cycad iam going with ciricinailis.

[wimmie]

Why?

[Merlyn]

@wimmie here is my diagnostic key for telling these similar-looking Cycas apart:

• Circinalis 80-90 degree insertion angle on rachis w/long tapering tip, raised rib above, visible but flat midrib below.
• Thouarsii 45-60 degrees with a more rounded tip, shiny big grooved/recessed midrib on top, pale w/a raised rib underside, bluish haze on new flush.
• Rumphii 90 deg leaves glossy green w/flat midrib above, and very pale w/raised midrib below.
• Seemannii deep green 45-70 degrees midrib flat above and raised below.

Based on this it probably isn't Rumphii, as the leaves tend to sweep forward, i.e. 70ish degree insertion angle.  If it doesn't fit the above descriptions it could also be something like Edentata/Litoralis or Pectinata.  The ripples on the leaves are distinctive too, though I can't quite place it.

[happypalms]

On 11/27/2024 at 9:00 AM, wimmie said:

Why?

It looks like one I have in my garden.

[Merlyn]

@wimmie I'm guessing Seemannii on this one:

From the species description I don't think it can be Circinalis.  Granted, I am zooming in on photos that get a little pixelated, but it looks like it has a raised pale midrib on the bottom of the leaf and a recessed pale midrib on the top of the leaf.  That rules out Circinalis and leaves Thouarsii and Seemannii.  The ends of the leaves are tapered and pointy, which rules out Thouarsii.

I'm still not convinced it isn't something entirely different, like Diannanensis.  The ripply leaves might just be from growing indoors and being stretched out.  But (going from possibly faulty memory here) I am not sure that any of the four options I mentioned have ripply leaves. 

[wimmie]

55 minutes ago, Merlyn said:

@wimmie I'm guessing Seemannii on this one:

From the species description I don't think it can be Circinalis.  Granted, I am zooming in on photos that get a little pixelated, but it looks like it has a raised pale midrib on the bottom of the leaf and a recessed pale midrib on the top of the leaf.  That rules out Circinalis and leaves Thouarsii and Seemannii.  The ends of the leaves are tapered and pointy, which rules out Thouarsii.

I'm still not convinced it isn't something entirely different, like Diannanensis.  The ripply leaves might just be from growing indoors and being stretched out.  But (going from possibly faulty memory here) I am not sure that any of the four options I mentioned have ripply leaves. 

Thanks; I'm going to chew over the reaction for a while!

[wimmie]

Still chewing, but I also have four new photo's. The first two are from a similar plant (about the same age) that I bought as a thouarsii, the latter two are from the rumphi/circinalis. From your reactions I have to doubt whether the first plant is a thouarsii because of the pointed leaflets and the other one? I still don't know!

[Merlyn]

@wimmie I think I misinterpreted the earlier pictures.  Below I'm guessing:

• The leaves are swept forward around 45 degrees, maybe a little bit less.  That rules out Circinalis and Rumphii, which have an insertion angle very close to perpendicular to the rachis.  Thouarsii and Rumphii are possibles, with 45-60 or 45-70 degree angles.
• The top rib is raised above the leaf surface, which makes this plant likely to be Thouarsii.  Seemannii is more recessed on the top side.
• The leaflets are a bit wider and more "blunt" or "rounded" near the tip.  That's also consistent with Thouarsii.

I was at Leu Gardens yesterday and took the picture of their ~1m trunk Seemannii.  This is in a lot of shade, so it's stretched out a bit:

Here is the top side of the leaflets, looks very much like your first two pictures.  The leaf profile looks sort of like my sketch.  The leaf is slightly curved downwards at the edges, and the rib is just a little bit recessed but mostly flat on top.  On the bottom it's raised and pale:

And the bottom side is also deep green with a raised pale midrib:

[Merlyn]

And for reference, here's a cluster of three smallish Thouarsii in my front yard.  I bought these offsets from a lady with a literal "tree" with about 10 feet of trunk on it.  I've ID'd them as Thouarsii...but as with all my other IDs I may well be wrong!!!

Here's the top side of the leaf.  The insertion angle is somewhere around 50-60 degrees, with a big slightly raised rib on top.  The leaves are somewhat tapered, and somewhat pointy:

And the bottom side is pale green with a large raised rib.  These also flush very pale blue:

[Merlyn]

And to throw some additional confusion in here, this is a Cycas Edentata/Litoralis that I bought from a local cycad expert:

[wimmie]

Total confusion overhere, guys, but I think I am going to honor the initial names I got for these Cycads, the first came as a thouarsii, the second as rumphi. Thanks all for your help!

[Merlyn]

@wimmie to clarify my ID guesses, I think this one is Seemannii:

and I think this one is Thouarsii:

When they get large enough to cone it should be easy to make a positive ID.

[wimmie]

Merlyn, I am 74 years old, so I don't think that is going to happen because I have to grow them in a container.