Tail furcations in lizards: a revised summary and the second report of tail duplication in the Western Fence Lizard, Sceloporus occidentalis Baird & Girard, 1852

We report a second instance of tail duplication in Sceloporus occidentalis and provide an updated list of all available data on tail furcations in lizards. The two previous comprehensive lists by Barr et al. (2020) and Henle and Grimm-Seyfahrt (2020) appeared in the same year and, despite considerable overlap, some discrepancies exist and are addressed herein. We also found a sizeable number of furcation reports published since 2020 (and a few from earlier years omitted from previous lists). We now list furcations in 250 lizard species from 25 families, with a significant majority (91%) being bifid tails. In 13% of species higher tail numbers may occur in addition to bifid tails, and in 9% of species only multiple tails have been observed. Based on the accelerated reporting in the two most recent decades, we surmise that furcations are not particularly rare or unusual, and that the activity of citizen scientists may contribute to a better understanding of this phenomenon.