Investigations of angiosperms from the eocene of North America: A new Juglandaceous catkin

Abstract

A new type of catkin allied with the Alfaroa—Oreomunnea—Engelhardia complex of the Juglandaceae has been recovered from the sediments of the middle Eocene Claiborne Formation in the southeastern United States. This catkin is distinct from Eokachyra (another staminate catkin from the Claiborne Formation allied with the same complex of extant genera as the new fossils) in having smaller florets, different bract morphology, possibly more floral envelope parts, and pollen decidedly different in size and morphology. This fossil inflorescence seems to be most closely allied with an extant species that is presently indigenous to southeast Asia. Variation in pollen morphology and its ramifications are considered in the new type of catkin and in Eokachyra.