Exine ultrastructure in pollen grains of Classopollis Pflug from the Cretaceous of Lebanon

Pollen grains of Classopollis Pflug from the Cretaceous deposits of Lebanon were studied by means of light and electron microscopy. Ultrastructurally, they are similar to pollen grains, extracted from Classostrobus comptonensis Alvin, Spicer et Watson from the Barremian of England. The differences concern the shape and size of spinules, ultrastructure of apertural regions, and preservation of the endexine. An analysis of our data and published results revealed three types of infratectum existed in members of Circumpolles: (1) with branchy elements, (2) with columella-like non-branching elements, and (3) with large granules arranged in one row. The palynological assemblage is described in detail; problems of dating are discussed.