Thu M. Tran

Document Type

Honors Thesis


The Gymnophtalminae family comprises over 250 lizard species. Many of these microteiids present with reduced limbs that contribute to their snake-like appearance. Several predictions regarding limb reduction arise from genetic and environmental influence; however, there is limited literature supporting the impact of limb reduction on the pectoral girdle. Five Gymnophtalminae species were selected, and Dristhi software was used to perform CT segmentation to view their pectoral bones. Echinosaura horrida presents with the most developed pectoral structure, as this is a fully developed quadruped species. Whilst Calyptommatus leiolepis presents with the most reduction with a thinner structure and diverges from a traditional girdle. These findings support the hypothesis of reduced limbs reducing pectoral structure as C. leiolepis have absent forearms. Likewise, the well-developed lizards present with a well-developed pectoral girdle. Further research should be conducted to compare pectoral reduction amongst other families to help support this hypothesis.

Publication Date




Faculty Mentor of Honors Project

Walter Schargel



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