Research Training Program

Smithsonian Institution
National Museum of Natural History

PROJECT SUMMARY
1997

Brian Yang
University of Michigan
Ann Arbor, Michigan
Kevin de Queiroz, Ph.D.
Supervising Scientist
Department of Vertebrate Zoology
"The NMNH Research Training Program provided me with invaluable experience in collections based research."

Species limits in the earless lizard Holbrookia maculate (Squamata: Iguanidae)

ABSTRACT
The iguanid genus Holbrookia is distributed throughout the the Great Plains, and parts of the Sonoran, Mojave, and Chihuahuan Desert regions of the United States and Mexico. Many of the plains and plateaus upon which these lizards occur have become subdivided and thereby isolated by erosional processes. As a result of this habitat separation, a considerable amount of variation has been observed among isolated populations of these lizards. The variability within Holbrookia presents difficult and unresolved taxonomic problems. Previously collected molecular data indicates that certain subspecies of Holbrookia maculate from southeastern Arizona and southwestern New Mexico are in fact distinct species. As a result of these findings, supplemental morphological data was needed in order to help clarify the taxonomic problems within this complex of lizards. Morphological data was collected on populations of H. m. flavilenta, H. m. pulchra, and H. m. thermophila and subjected to Principle Components Analysis and Discriminant Functions Analysis. The preliminary results of these analyses were consistent with the results of the molecular data. Specific limits on morphological variation are established and geographic ranges of the different subspecies of Holbrookia maculate are discussed.

This research was supported by a grant from the National Science Foundation's Research Experience for Undergraduates Program-award number: BIR-951331.

Letter of Gratitude