Toes, tails, and heads: Morphological anomalies in different lizard species of Central Mexico

Morphological anomalies in reptiles can originate from genetic factors, trauma, infections, or environmental conditions and affect key aspects such as locomotion, behavior, and survival. Here, we document 24 cases of morphological anomalies in the toes, tails, and heads of eight lizard species of three families (Anguidae, Phrynosomatidae, and Scincidae) from Hidalgo, Mexico; which were recorded between January 2023 and August 2025 in different municipalities. Most anomalies occurred in the limbs, identifying cases of brachydactyly, ectrodactyly, and adactyly, alone or in combination. Additionally, three individuals with bifurcated tails and two with head anomalies were identified. The genetic background, environmental factors, or failed predatory events may explain the origin of these anomalies in the wild. This highlights the importance of recording these cases to understand their frequency, potential causes, and effects on the biology and ecology of reptiles.