Honors Theses

Date of Award

Spring 5-9-2020

Document Type

Undergraduate Thesis


Geology and Geological Engineering

First Advisor

Louis Zachos

Second Advisor

Jennifer Gifford

Third Advisor

Gregory Easson

Relational Format



Neozanthopsis Americana is a crab from the middle Eocene Claiborne Group that lived along the Gulf of Mexico, and has been documented in Texas and Louisiana. This species was discovered by Rathburn (1928) and was later amended and added to by Schweitzer (2014). The specimens in this paper are found near Natchitoches, Louisiana, and along with their accompanying fossils are used to describe the depositional environment of the locality. Sediments were taken from the site and analyzed under a standard microscope for microfossils, which were collected and further analyzed under scanning electron microscope. In addition to the microfossils, the cuticles from six crab specimens were also examined under the scanning electron microscope. Many foraminifera were collected, and along with morphological features of the crab and associated macrofauna, a depositional environment was described. The site was probably on the edge of the inner shelf in a biostrome environment. This location would have been mechanically active and connected to the ocean, and likely was a molting/breeding ground for the crabs.

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