According to GRIN taxonomy, Vigna catjang (Burm. f.) Walp. and Vigna cylindrica (L.) Skeels are both synonymous with Vigna unguiculata (L.) Walp. subsp. unguiculata Biflora Group. They list several accessions, with photos of flower & seed. They are the same species as cowpeas & yardlongs, but a different group.

I tried to link my GRIN search results for the subspecies, but it wouldn't work. Here is one of their accessions, you can click on the thumbnail photos on the bottom of the page: GRIN accession for catjang From this record, you can also click on the species (at the top of the page), then on the resulting page, click the "include images" box, and hit "list"... which will duplicate my search results.

I wonder if the seller has adzuki in colors other than red...

The picture they used, more than anything, was what interested me in this seed. Hopefully reality matches eBay image, and that it tastes worthwhile.

The seed they pictured on their ad was NOT the seed in the package. The packaging was what I received though. This appears to be Lablab bean. Attractive, but a bit harder to cook. If I could read Chinese the packaging might have told me this. :/

Sorry to hear about the mixup; I was looking forward to hearing more about that bean, and how that sub-species differs from its cousins.