Abstract

Abstract Cheirolepidiaceous conifer pollen cones (Classostrobus arkansensis new species) from the Lower Cretaceous (Aptian/Albian) Holly Creek Formation of Arkansas, some still attached to Pseudofrenelopsis parceramosa Fontaine, shoots, bear helically arranged, semipeltate to dorsiventral microsporophylls with abaxially situated pollen masses. The in situ Classopollis Pflug, 1953 pollen and orbicule outer sculpturing consists of short spinules. The abaxial epidermis of the microsporophyll head consists of a stomatiferous central region of isodiametric cells bearing hollow papillae with rounded apices and a nonstomatiferous marginal area of elongate, nonpapillate cells. The head abaxial cuticles are thin relative to those of the shoot internodes. A cutinized hypodermis is lacking. Previously described pollen cones of Classostrobus comptonensis (Alvin et al., 1994) from the English Wealden (Barremian) are also associated with P. parceramosa shoots; however, they differ substantially from the Arkansas cones ...

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.