Abstract Detail

Paleobotany

Allen, Sarah [1], Meyer, Herbert [1], Thornton, Carolyn [2], Manchester, Steven [3].

Incertae sedis: Unidentified late Eocene plants in the collection of Florissant Fossil Beds National Monument.

Florissant Fossil Beds National Monument preserves one of the richest paleontological sites in the world with about 1800 described plant and animal species, of which approximately 125 are plant macrofossils from the shales of the late Eocene Florissant Formation. The plant fossils from Florissant were first described by paleobotanist Leo Lesquereux in the 1870s and 1880s. Other early contributions include work by T.D.A. Cockerell. These early identifications were revised in an extensive monograph by H.D. MacGinitie in 1953, who also included new material from his excavations. Some of MacGinitie's species have been updated and several new species have been described in the ensuing decades, yet new excavations continue to expand known diversity. The National Park Service collections at Florissant Fossil Beds National Monument in central Colorado includes >4,500 plant specimens. Of these, over 1,000 specimens are not identified to the species level. The park's collection serves as a previously unidentified sample with material from excavation sites in all units of the Florissant Formation. Many specimens are too poorly preserved to be identified, others have been recognized at the family level, and still others are well-preserved and/or distinctive, but cannot be matched to anything already in the published literature. This last category, including flowers, fruits/seeds, and leaves, is the focus here. There are approximately 19 unidentified flower morphotypes. The flowers are preserved both laterally and transversely, therefore it is possible that some of the flowers are the same species in different orientations. The gynoecium and/or androecium is present on some specimens. The unidentified fruits and seeds are also diverse with approximately 35 different morphotypes. Hypotheses about the taxonomic affinities of these unknown reproductive morphotypes remain elusive, but initial analyses suggest affinities to the Sapindales, Rosaceae, Fabaceae, Myrtaceae, Rhamnaceae, Vitaceae, and Salicaceae. In addition, there are roughly 60 leaf morphotypes (many represented by single specimens) in the Florissant collection that have defining characteristics, but that cannot be assigned to a taxon already described in the literature. The unidentified leaves include 16 morphotypes that were collected in an unbiased field collection in 2009 and 2010 within the monument's boundaries. This sub-collection serves as a new random sample that could be used for future diversity analyses such as rarefaction.

1 - Florissant Fossil Beds National Monument, PO Box 185, Florissant, CO, 80816, USA
2 - Harvard University Herbaria, 22 Divinity Avenue, Cambridge, MA , 02138, USA
3 - Florida Museum Of Natural History, Po Box 117800, Gainesville, FL, 32611, United States

Keywords:
paleobotany
Eocene
Florissant
National Park Service
Leaves
flowers
fruits.

Presentation Type: Poster
Session: P, Paleobotany posters
Location: Grand Ballroom - Exhibit Hall/Mayo Civic Center
Date: Monday, July 23rd, 2018
Time: 5:30 PM This poster will be presented at 6:15 pm. The Poster Session runs from 5:30 pm to 7:00 pm. Posters with odd poster numbers are presented at 5:30 pm, and posters with even poster numbers are presented at 6:15 pm.
Number: PPB002
Abstract ID:629
Candidate for Awards:None