Extinct ulmaceous fruits from the Tertiary of Europe and Western North America

Abstract

Fossil winged fruits formerly attributed to “ Embothrites borealis” Unger from the Upper Eocene to Upper Miocene of Europe and to “ Banksites” lineatus Lesquereux from the Middle Eocene to Lower Oligocene of western North America represent an extinct genus in the subfamily Ulmoideae of the Ulmaceae. This assignment is confirmed by a persistent stigmatic area at the distal tip of the fruit wing. Both of the generic names cited above, and the specific epithet borealis, have been applied to these extinct ulmaceous fruits for more than a century, but were originally applied to unrelated, non-ulmaceous material. The genus Cedrelospermum Saporta has priority and the correct species names are Cedrelospermum leptospermum (Ettingshausen) comb. nov. and C. lineatum (Lesq.) comb. nov. Leaves of Tremophyllum Rüffle, which occur in association with C. leptospermum and which have been found attached to branches bearing C. lineatum fruits, also show features characteristic of the Ulmoideae. The stratigraphic and geographic distribution of Cedrelospermum augments paleobotanical support for the concept of an Eocene North Atlantic land connection between North America and Europe.