Permineralized cardiocarpalean ovules in wetland vegetation from Early Permian volcaniclastic sediments of China

In this paper we report the first occurrence of permineralized plant fossil s in volcaniclastic lithologies from China and in doing so describe a new s pecies of cardiocarpalean ovule permineralized within tuffaceous sediments from a recently discovered locality near Pingqaan, Hebei Province, North Ch ina. The tuff is part of the Early Permian Taiyuan Formation which contains a diverse fossil plant assemblage that includes cordaitean spermatophytes, lepidodendralean lycophytes, equisetophytes, and filicalean ferns, all of which were typical of Permian floras of northern China at this time. Specim ens of Cardiocarpus dabiziae sp. nov. have the characteristic platyspermic shape and vascularization of cardiocarpalean ovules, and display prominent protuberances on the exterior of the integument. The integument of the ovul e is composed of three layers; a thick sarcotesta, a thin and comparatively dense sclerotesta, and a single layer of large endotesta cells. The pollen chamber produces a slender nucellar beak. In several specimens the megaspo re membrane contains well-developed tissue of the megagametophyte. The ovul es have prominent external integumentary protuberances which;suggest that w ell-developed systems of plant/animal interactions were operative in Early Permian wetland biotas of the Cathaysian realm.