RODRIGUEZ-ROMERO, Felipe de Jesús; GALINDO-GIL, Sandra    MORENO-BARAJAS, Ruth. Morphological variation of the cephalic scales in Sceloporus aeneus and Sceloporus bicanthalis: species separation by geometric morphometry. Rev. Mex. Biodiv. []. 2023, 94, e943995.   26--2024. ISSN 2007-8706.  https://doi.org/10.22201/ib.20078706e.2023.94.3995.

Sceloporus aeneus and Sceloporus bicanthalis have recently been split into different species, they are similar in morphology and life history but differ in reproductive mode and number of canthal scales. However, this last character is highly variable, but it is the only morphological character that is currently used to differentiate them. In the present work, the degree of morphological variation of the cephalic scales was analyzed, using geometric morphometry and multivariate statistics to determine if the use of these methods allows differentiating both species. Digital photographs of S. aeneus and S. bicanthalis were used and scale marks were placed on the dorsal, ventral and lateral region of the head. The results show significant differences in the shape of the scales between the 2 species. Therefore, each species presents a defined morphotype in terms of skull scutellation. The analysis suggests that both species can be more reliably identified by variations in the shape of the parietal and interparietal scales than by the number of canthal scales.

: Cranial scutellation; Squamata; Canthal scales; Sister species; High mountains.