Viola labradorica 'purpurea' = V. riviniana? (what's the story)
Just following up on a comment someone made in a previous thread. To provide context for my question, I've been doing research on low-growing, eastern U.S. native wildflowers suitable for a low "front border" to a native perennial garden (with medium to tall plants). Of course, violets are generally low-growing, and there are many North American species. In looking through the catalogs of native plant nurseries near my area, I've seen several reference to Viola labradorica, or V. labradorica purpurea. This puzzled me a bit because reference books say that V. labradorica is native to Labrador, Greenland, and Nova Scotia. Most plants from that far "up north" wouldn't be happy in our hot summers, and wouldn't be carried by local nurseries. The comment in the other thread suggests the answer to this mystery: the purported V. labradorica is really V. riviniana, a more adaptable European not North American species. Is this now generally accepted (at least by knowledgeable botanists)? If so, why does the apparent mis-identification persist, in other words why don't the nurseries start referring to the plant as V. riviniana purpurea?