Ushia - a new genus from Kamyshin Paleocene flora

Abstract

Ushia kamyschinensis (Goeppert) n. gen. and n. comb. is established as a monotypic genus for leaves peculiar to the Paleocene of the U. S. S. R. The specimen designated as the holotype is that described by Goeppert in 1845 as Phyllites kamyschinensis from the Paleocene (Saratov Stage) found at Mt. Ushi near Kamyshin. The leaf, although very polymorphous, is ovate-oval to ovateprolate in outline with a broadly rounded to rounded cuneate base, generally somewhat asymmetrical. The leaf margin is entire below the basal secondary veins, crenate to crenulate above. The veins are coarse and prominent. Secondary veins alternate, 8-12 (14) in number, straight or slightly arcuate. Tertiary veins are almost perpendicular to secondary veins, mostly unbranched. Lowest pair of secondary veins branch unilaterally outward, the branchlets forming loops along the base of the leaf. This latter character differentiates the leaf from other members of the Fagaceae, the family to which Ushia most probably should be assigned. --...