Clematis viorna

Clematis viorna L.
Engl.: leather flower, vasevine.
Bot. syn.: Clematis beadlei (Small) Erickson, Clematis gattingeri Small, Coriflora beadlei (Small) W. A. Weber, Coriflora gattingeri (Small) W. A. Weber, Coriflora viorna (L.) W. A. Weber, Viorna beadlei Small, Viorna flaccida (Small) Small, Viorna gattingeri (Small) Small, Viorna ridgwayi Standl., Viorna viorna (L.) Small.