A preliminary conspectus of the Allon flora from the Late Cretaceous (LateSantonian) of central Georgia, USA

A preliminary conspectus of the fossil flora from the Allon locality, in Cr awford County central Georgia, documents the presence of at least 63 distin ct plant organs, based on macrofossils and mesofossils, but excluding dispe rsed pollen and spores. The fossils are preserved in a clay lens within the Buffalo Creek Member of the Gaillard Formation, and are of late Santonian (Late Cretaceous) age. In general, macrofossils are sparse at this site, bu t abundant mesofossils have been isolated from bulk samples by sieving. The flora includes sporophytes and gametophytes of fossil mosses (e.g., Eopoly trichum antiquum, Campylopodium allonense), ferns (e.g., cf. Boodlepteris), and conifers, but is dominated by the diverse and abundant remains of angi osperms. Angiosperms in the flora include cf. Detrusandra (Magnoliales), Ma uldinia sp. (Lauraceae), Allonia decandra (Hamamelidaceae), and Parasauraui a allonensis (Actinidiaceae). Especially abundant are flowers and cupules o f two species of Fagaceae sensu late (Protofagacea allonensis, Antiquacupul a sulcata). The flora also includes fossil flowers of Caryanthus sp. (Jugla ndales/Myricales) and Bedellia pusilla (cf. Betulaceae), which comprise the first record of Normapolles-producing flowers from North America. The stru ctural and systematic diversity of angiosperms in the Allon flora is compar able: to that at other Turonian-Campanian sites in eastern North America an d Europe. Together, these fossil floras indicate that angiosperms, and espe cially eudicots, were already diverse at this relatively early stage in ang iosperm evolution. The source vegetation represented by the Allon fossil as semblage was dominated by angiosperms, probably with taxodiaceous conifers also common. preservation of most of the mesofossils as charcoal indicates that fire may have been an important factor contributing to frequent distur bance of the source plant community.