Alison Ngo

Document Type

Honors Thesis


Echinosaura is a semi-aquatic group of lizards of the Gymnophthalmidae family, which inhabits the streams of the tropical forests of Costa Rica down to Ecuador along the Andes mountains. Echinosaura is composed of seven species: E. brachycephala, E. centralis, E. horrida, E. keyi, E. orcesi, E. palmeri, E. panamensis. Recent studies have proposed a well-resolved phylogenetic hypothesis for this genus, based on molecular data. However, there is a lack of knowledge on morphological aspects, such as their osteology. Here, we perform a bone-by-bone description and illustration of the skull of E. horrida using CT-scan data. We found variation in characters that allow differentiating this genus from other gymnophthalmids with available osteological descriptions. Some of these character states are the general skull shape, dorsal sculpturing on the roof bones, teeth count, and posterior process of the jugal. The data generated here is important to bring light to the morphological evolution of Gymnophthalmidae.

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