Journal of the Arkansas Academy of Science

Volume 26 Article 6

1972 Taxonomic Note on in Northeastern Arkansas Eugene B. Whittlake Arkansas State University

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Recommended Citation Whittlake, Eugene B. (1972) "Taxonomic Note on Fossil Glyptostrobus in Northeastern Arkansas," Journal of the Arkansas Academy of Science: Vol. 26 , Article 6. Available at: http://scholarworks.uark.edu/jaas/vol26/iss1/6

This article is available for use under the Creative Commons license: Attribution-NoDerivatives 4.0 International (CC BY-ND 4.0). Users are able to read, download, copy, print, distribute, search, link to the full texts of these articles, or use them for any other lawful purpose, without asking prior permission from the publisher or the author. This Article is brought to you for free and open access by ScholarWorks@UARK. It has been accepted for inclusion in Journal of the Arkansas Academy of Science by an authorized editor of ScholarWorks@UARK. For more information, please contact [email protected], [email protected]. Journal of the Arkansas Academy of Science, Vol. 26 [1972], Art. 6 Taxonomic Note on Fossil Glyptostrobus in Northeastern Arkansas EUGENE B.WITTLAKE Arkansas State University, State University, Arkansas 72467

ABSTRACT Twopapers by Brown (1936, 1962) are reviewed and discussed in relation to the validity of specific names applied to the fossil Glyptostrobus as found in North American deposits. Evidence ispresented supporting the contention that G. nordenskioldi Brown n. comb, is the valid name for Glyptostrobus specimens from the Hooker site of northeastern Arkansas.

Numerous specimens of a fossil Glyptostrobus have been The Hooker deposit specimens ofcone-scales are shorter and described from the Hooker site and designated as G. europaeus broader than those of other species. The cone-scales and (Brongn.) Heer (Wittlake, 1970). As the study of these microsporophylls are numerous and scattered through the specimens proceeds, more and more characteristics are found clay-shale of this site, indicating a rapid and general ofandrostrobili, gynostrobili, cone-scales, and seeds which vary disintegration ofboth male and female cones. The deposit itself considerably from those ofG. pensilis Koch, the livingspecies, is of Early Eocene age. Therefore, the Glyptostrobus from and G. europaeus. G. europaeus is the species assigned by Hooker agrees with all characteristics for G. dakotensis several authors to remains found inEocene formations ofNorth outlined by Brown (1936). He suggested that G. oregonensis America. Brown should be applied to Glyptostrobus remains in the American Miocene. Two papers by Brown (1936, 1962) regarding the validity of specific names applied to the genus Glyptostrobus in North In conclusion, the positive identification of Glyptostrobus America have come to the attention ofthe author. Inhis earlier twigs from any fossil site not associated with seeds or work, Brown (1936) assigned the name G. dakotensis to gynostrobili is a very tenuous exercise. Because numerous androstrobili and foliage of Eocene specimens found near seeds, gynostrobili, and androstrobili are associated with Elbowoods, North Dakota, and suggested that all American cupressoid, cryptomeriod, and taxodioid foliage at the Hooker Eocene species of this genus should be included in this taxon. locality, there is no problem as to the generic identity of these • Hebased this recommendation on the followingcharacteristics: specimens. Further, with the variations noted, there is no "1. the cone-scales are, on the average shorter and broader, 2. problem for their proper specific disposition. Henceforth, G. The cone-scales occur scattered and detached, a characteristic europaeus as reported by Wittlake (1970) from the Upper apparently not shown by G. europaeus or the present day G. Wilcox Formation, Lower Eocene of northeastern Arkansas, pensilis. whose cones remain intact and do not disintegrate willbe designated as G. nordenskioldi (Heer) Brown. readily after ripening, 3. The species occur in the lower part of the American Eocene, a considerable time interval from the LITERATURE CITED typical G. europaeus ofthe European Miocene." BROWN, R. W. 1936. The genus Glyptostrobus in America. Washington Acad. Sci. J. 26:353-357 Inhis 1962 work, Brown stated that Heer (1871) assigned seeds and perhaps some cone-scales possessing the BROWN, R. W. 1962. floraofthe Rocky Mountains characteristics cited in his 1936 work under G. dakotensis and and Great Plains. U.S. Geol. Sur. Prof. Paper 375, p. 49, associated with Glyptostrobus foliage (called at the time pi. 11. nordenskioldi) to a species from Spetzenbergen. Heplaced in synonomy G. dakotensis under G. HEER, OSWALD. 1871. Flora Artica. V.2, p. 32, 26. nordenskioldi (Heer) Brown. This taxon includes then Glyptostrobus remains found in Paleocene and Eocene WITTLAKE, E. B. 1970. Glyptostrobus europaeus (Brong.) localities ofNorth America. Heer in Arkansas. Arkansas Acad. Sci. Proc. 24:44-46.

Published by Arkansas Academy ofArkansas Science, 1972Academy of Science Proceedings, Vol. XXVI,1972 13 I Journal of the Arkansas Academy of Science, Vol. 26 [1972], Art. 6

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