Permineralized Cardiocarpalean Ovules in Wetland Vegetation from Early Permian Volcaniclastic Sediments of China

Abstract

ABSTRACT. In this paper we report the ®rst occurrence of permineralized plant fossils in volcaniclastic lithologies from China and in doing so describe a new species of cardiocarpalean ovule permineralized within tuffaceous sediments from a recently discovered locality near Pingquan, Hebei Province, North China. 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 ®licalean ferns, all of which were typical of Permian¯oras of northern China at this time. Specimens 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 ovule 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 megaspore membrane contains well-developed tissue of the megagametophyte. The ovules have prominent external integumentary protuberances which suggest that well-developed systems of plant/animal interactions were operative in Early Permian wetland biotas of the Cathaysian realm.

Cordaitalean Seed Plants from the Early Permian of North China. III. Reconstruction of the Shanxioxylon taiyuanense Plant

“…For example, most disarticulated fossil assemblages that are rich in seed plant remains contain a surplus of ''orphaned'' ovule species, because of their relative ease of transport (Bateman 1991;Hilton et al 2001aHilton et al , 2003. However, the Taiyuan cordaitaleans appear to be a remarkable exception to this statistical pessimism.…”

“…Here, we reconstruct the third of three whole-plant cordaitaleans present in these deposits, Shanxioxylon taiyuanense. Materials described, initially in Chinese, include stems (Tian and Wang 1988;Wang 1997Wang , 1998, ovulate shoot systems (Wang and Tian 1993a), ovules (Wang and Tian 1991b;Hilton et al 2001aHilton et al , 2003Wang et al 2003a), male shoot systems (Wang and Tian 1991a), leaves , and roots (Wang and Tian 1993b). The contrasting levels of evidence supporting each of the three whole-plant reconstructions are then reviewed, before consideration of the taphonomy and paleoecology of the S. taiyuanense plant and the other contemporaneous Chinese cordaitalean whole plants, S. sinense and C. tianii.…”

Anatomically Preserved Pteridosperm Stems and Rachises from Permian Floras of China

“…Early work on permineralized seed plants by Wang and Tian (Wang 1998;Wang et al 2003b;Hilton et al 2008) concentrated on cordaitean coniferophytes from the Early Permian Taiyuan Formation from which three whole plant species have now been reconstructed. Other accounts have focused on isolated ovules (Hilton et al 2001a(Hilton et al , 2002Wang et al 2006; L. J. Seyfullah, J. Hilton, M. D. Sutton, and S.-J.…”

“…Hilton, M. D. Sutton, and S.-J. Wang, unpublished manuscript) from which a diversity of cardiocarpalean ovules are now known ) as well as a smaller number of hydrasperman-and medullosan-type ovules (see Hilton et al 2001aHilton et al , 2001b. In comparison, research on pteridosperm vegetative organs from the permineralized record is limited and lacks detailed descriptive treatments of individual taxa.…”

Cordaitalean Seed Plants from the Early Permian of North China. II. Reconstruction of Cordaixylon tianii

“…These investigations have resulted in a series of articles detailing individual cordaitalean organs from the Early Permian Taiyuan Formation of northern China. Plants described include stems (Wang 1997(Wang , 1998, ovulate shoot systems (Wang and Tian 1993a), ovules (Wang and Tian 1991b;Hilton et al 2001a; Wang et al 2003a), male shoot systems (Wang and Tian 1991a), leaves , and roots (Wang and Tian 1993b). Most of these cordaitalean organs represent new species belonging to genera that were previously recognized from the Pennsylvanian and earliest Permian floras of Euramerica (Phillips 1980;Phillips et al 1985;Doubinger et al 1996).…”