Ulmus laevis
Ulmus laevis" var. "celtidea is a putative variety of European White Elm first described by Rogowicz, who found the tree in 1856 along the river Dnjepr near Chernihiv in what is now northern Ukraine. The type specimen is held at the National Herbarium of Ukraine. The variety was first named as "Ulmus pedunculata" var. "celtidea". Litvinov (1908) considered it a species, calling it "Ulmus celtidea" , a view not upheld by other authorities.