Theses and Dissertations - UTB/UTPA

Date of Award


Document Type


Degree Name

Master of Science (MS)



First Advisor

Dr. Brad C. Henry Jr.

Second Advisor

Dr. Anxiu Kuang

Third Advisor

Dr. Kenneth Summy


External egg morphology of ten species of Lower Rio Grande Valley (LRGV) mayflies are compared using scanning electron microscopy (SEM) and a taxonomic key to the eggs is provided. The eggs of five species are described here for the first time. Preserved female adults or subadults were critical-point dried using liquid CO2 . The eggs were removed and placed on metal stubs for sputter coating with gold/palladium. The coated eggs were then observed and photographed by SEM. The morphological features described were the chorionic sculpturing, polar caps, accessory attachment structures, and micropyles. This is the first mayfly egg comparison and key to the genera of mayfly eggs from the LRGV.


Copyright 2003 Maria D. De Leon. All Rights Reserved.

Granting Institution

University of Texas-Pan American