I checked for the name Doryopteris cordata but it doesn't seem to exist, the closest being D. cordifolia. This is a page of illustrations, you might be able to pick up on something there:
http://plantillustrations.org/taxa.php?id_taxon=%2019882

tropicbreezent,

That's exactly the problem I was running into--it doesn't seem to exist in most databases. However, here's one that does seem to have it:

http://zipcodezoo.com/Key/Plantae/Doryopteris_Genus.asp

If one does a search--Google or Google images, there are plants being sold under the name "Doryopteris cordata" that appear very similar or identical to the one I bought.

Based on what I can find it's not clear whether it's a valid name or one that is just being used to sell the plant.

Here is a link that might be useful: Doryopteris species (link repeated from above)

I give a link to the Google image search below

Here is a link that might be useful: Google image search for

I did a search on the Kew Gardens site, they're generally regarded as the final word on plant species. Also The Plantlist site which is a collaboration between Kew, Missouri Botanic Gardens, and a few others. That came up with zero for that name. Also did a search on the ePIC site and got the following result:

The following matches were found for "Doryopteris cordata":

(Your search term was understood as: Genus = Doryopteris and species = cordata)

*
Plant names
o No matching entries found in IPNI
o No matching entries found in WCSP
*
Bibliographies
o No matching references found in Kew Record
o No matching references found in Economic botany bibliography
o No matching references found in Library Catalogue
o No matching references found in Micromorphology bibliography
*
Collections
o No matching specimens found in Herbarium Catalogue
o No matching specimens found in Economic Botany collection
o No matching specimens found in Living collection
*
Species-level information
o No matching records found in Seed Information
o No matching species found in SEPASAL
*
Floras
o No matching entries found in Flora Zambesiaca

It's not unusual for incorrect names to be used commercially. Came up before about Alocasia Hilo Beauty which was being sold under that name before it was actually formally described. Turned out it was a Caladium, but continues to be sold as Alocasia Hilo Beauty.

I found an interesting discussion about what may be the same plant, from 2004. It is suggsted to be Doryopteris pilosa var. gemmifera. I'm not finding a good photo, but it does seem to closely resemble the herbarium specimen (link to photo below).

http://www.hort.net/lists/ferns/dec04/msg00009.html

Doryopteris pilosa var. gemmifera was published recently (1990). I can't access that publication, but I did track down the email of the corresponding author. No doubt he will be able to ID the plant, so I'll send him an email.

Here is a link that might be useful: Herberium specimen of Doryopteris pilosa var. gemmifera

It definitely looks like a good match.

I heard back from the guy who discovered Doryopteris pilosa var. gemmifera. He thought the photos of my plant looked very similar, but he concluded that it is more likely to be Doryopteris pilosa var. pilosa. I gather he didn't think the South African species would be available in the horticultural trade.

I guess without having the plant in your hands it would be difficult to be certain. That's probably why he opted for logic.