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Mid-Cretaceous megaspore floras from Maryland, USA

Published online by Cambridge University Press:  05 October 2015

Richard Lupia
Richard Lupia*
Affiliation:
Sam Noble Museum and ConocoPhillips School of Geology and Geophysics, University of Oklahoma, 2401 Chautauqua Avenue, Norman, OK 73072, USA, 〈rlupia@ou.edu〉
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Abstract

Bulk maceration of unconsolidated Potomac Group sediments collected from 12 samples of middle–late Albian and early Cenomanian age on the Elk Neck Peninsula, Maryland, yielded 14 genera and 18 species of megaspores. The identified megaspores have affinities to both heterosporous ferns, e.g., Arcellites and Molaspora, and to heterosporous lycopsids, e.g., Erlansonisporites, Minerisporites, and Paxillitriletes. Morphological variation within species is high, and most morphotypes differ from established taxa in one or more characters. Two new species—Dijkstraisporites praetextus and Verrutriletes diversus—are proposed. The composition of these middle–late Albian and early Cenomanian floras is a mixture of taxa previously recorded from Aptian and Santonian floras in North America. In addition, a fragmentary strobilus of selaginellalean affinity containing a megaspore and microspores is described.

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Journal of Paleontology , Volume 89 , Issue 3 , May 2015 , pp. 494 - 521
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Copyright © 2015, The Paleontological Society 

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