Systematics, Climate, and Ecology of Fossil and Extant Nyssa (Nyssaceae, Cornales) and Implications of Nyssa grayensis sp. nov. from the Gray Fossil Site, Northeast Tennessee

<p>The Late Hemphillian (latest Miocene or earliest Pliocene, 7-4.5 Ma) Gray Fossil Site in northeastern Tennessee is interpreted to represent a lacustrine paleokarst fed by a river or stream. This research focuses on the morphological and systematic relations of Nyssa endocarps (fruit pits) from the fossil site to extinct and extant Nyssa species. A combination of metric and nonmetric traits allows recognition of a new species: <em>Nyssa grayensis</em> sp. nov. This fossil species shares the most similarities with the extant <em>Nyssa ogeche</em> Bartram ex Marshall from southeast North America and the Eocene fossil <em>Nyssa eolignitica</em> Berry from western Tennessee. Affinities with <em>Nyssa ogeche</em> Bartram ex Marshall suggest a warmer winter climate than the present and periodically fluctuating water levels. Fossil vertebrates (<em>Alligator, Heloderma, Hesperotestudo</em>) and plants (Fossil relatives of <em>Ilex vomitoria, Quercus virginiana, Taxodium, Acer leucoderme</em>) with modern counterparts distributed in areas with mild winters support this interpretation.</p>

Name thesis:degree_name

MS (Master of Science)

Level thesis:degree_level

Thesis - unrestricted

Discipline thesis:degree_discipline

Biology

Year dc:date.issued

2013

Author dc:creator

• Noll, Nathan R

• Nyssa
• Endocarp
• Gray Fossil Site
• Miocene
• Pliocene
• Karst
• Biodiversity
• Climate
• Paleontology
• Plant Biology

Statement dc:rights

• Copyright by the authors.

Repository record dc:identifier

https://dc.etsu.edu/etd/1204

OAI identifier oai:identifier

oai:dc.etsu.edu:etd-2366