pollen specimen magnified

Spinozonocolpites echinatus, UF 18200-34219. Plate 1, figure 5 in David M. Jarzen and David L. Dilcher. 2006. Middle Eocene Terrestrial Palynomorphs from the Dolime Minerals and Gulf Hammock Quarries, Florida, U.S.A. Palynology, 30: 89-110.