We know there is difficulty in identifying the many forms of Aechmea nudicaulis but it solves nothing if names are given to different forms and nothing is written about them.
In 1998 I wrote to Harry Luther about the key in Smith & Downs not really working because I found so many that did not agree with the descriptions. Here is Harry's reply
Marie Selby Bot Gardens 23 Oct. 1998
Dear Derek;
I hope that you haven't spent too much time trying to sort out the various names in a key applied to A. nudicaulis. It is not worth the effort; in Brasil, especially from around Rio and south it is a variable taxon. Most of these names go with populations except for variegated clones, but are probably not biologically significant. I've seen living material of all except var. simulans (I've seen type material at HB). This has a typical cuspidata inflorescence but with rather narrow, pointed, spiny leaf blades. I should note that almost all of the material I've seen from Brazil has floral bracts conspicuous enough to be called var. cuspidata; only West Indian and Mexican & Central American (including some Venezuelan & Guyana plants) collections have very reduced or lacking floral bracts. I've not made an extensive study but the floral bract size doesn't seem to correlate with any other features (leaf number, flower color, conformation). Flower color is especially worthless as plants of var. capitata can have aureo-rosea color. In fact the only variation worth noting, in my opinion, is var. capitata with its congested head of erect flowers with a sulcate ovary ( = Aechmea sulcata Lindman ???)
Var. plurifolia isn't that different as plants fitting into that variety may have fewer leaves that are not at all distichous and are spirally arranged; the inflorescence is typical var. cuspidata.
I have about 20 collections of this species from Mexico to Ecuador and Parana/Sao Paulo border area of Brazil. A form from Dominican Republic is odd, somehat resembles simulans.
Yours truly,
Harry
Despite Harry's comments I concocted a key to try to help me understand what I was looking for and it is given here in case some of you want to try it.
Key to Aechmea nudicaulis by Butcher compiled from descriptions but does not link exactly to plant material in collections. This is confirmed by Harry Luther's comments - and Tanya Wendt's comments in the Bot Journ of the Linnaean Soc 125: 245-271. 1997.
| 1. | Plant | - more than 20 spreading ligulate leaves with red tip | var. plurifolia |
| 1a. | - about 20 erect leaves without red tip | 2 | |
| 2. | LEAVES | - linear triangular narrowing to a pungent tip Plant similar to A. purpureo-rosea |
var. simulans |
| 2a. | - ligulate forming a loose cylinder | 3 | |
| 3. | INFLORESCENCE | - dense, leaves banded,floral bracts minute, tips acuminate. Sepals yellow with pink tip, petals yellow |
var. capitata |
| 3a. | - lax | 4 | |
| 4. | LEAVES | - variegated | 5 |
| 4a. | - concolorous | 6 | |
| 5. | LEAVES | - variegated (form of cuspidata) | forma tabuleirensis |
| 5a. | - yellow marginated | var. flavomarginata | |
| 6. | FLORAL BRACTS | - kidney shaped and minute petals yellow | var. nudicaulis |
| 6a. | - triangular or elliptic, relatively conspicuous | 7 | |
| 7. | PETALS | - wholly yellow | 8 |
| 7a. | - red with yellow tip, sepals and ovary red | var. aureorosea | |
| 8. | SCAPE BRACTS | - smallish, evenly spread on scape | var. aequalis |
| 8a. | - clustered beneath inflorescence petals and sepals yellow | var. cuspidata |
When you have been through this and your plant does not fit the bill then refer to the Online Cultivar register. You should get at least 15 replies to give you even more checks to make. BUT please do not give your plant a cultivar name without giving detail to the Cultivar Registrar.
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