Early Seventies – Art Nouveau & New Romantic SFF Book Covers

Does anyone else recall the era when book covers looked like this one by Fred Winowski:

Here are a couple more examples that I remember from my childhood.  I always loved this cover:

and it’s very different from the one by Leo and Diane Dillon.

The Dillons did, however, create this stunning cover for the Odyssey, and it feels very much in the style above:

This one has a similar feel to me.

as does its sequel, by David McCall Johnston:

And the classic Earthsea cover by Pauline Ellison also seems related:

Here’s a couple from Jack Vance’s Lyonesse series. I associate this cover style with a number of books I adored in the early eighties, and I think it evolved from the earlier work, above.

Swordspoint by Ellen Kushner has this amazing cover by Thomas Canty, which causes me to think he also did the Lyonesse covers above.

I’ve asked around among my colleagues who do cover art, and no one has a name for this style or genre.  I have deeply positive, nostalgic associations with these covers (and these books) – and I’d love to find more covers in the same style.

Does anyone have any relevant information?

In my recollection the style gradually transitioned into work like Yvonne Gilbert’s (which I also love):

UPDATE

My friend, the very talented Echo Chernik, identified these covers as “Art-Nouveau Influenced.” Wikipedia identifies Thomas Canty as the pioneer of the “New Romantic” style, which seems to be the best descriptor for the later style that I associate with Tor books from the eighties.