Figure 10. Strict consensus tree of 32 most parsimonious trees (length=630 steps) from our unconstrained analysis without the “vertebrae-only” fossil taxa. Extinct taxa are in bold.
unconstrained morphological analyses fail to show a consensus North American clade as the result of a lack of characters for the post-cranial skeleton of Notophthalmus, combined with a deep
split of the Taricha and Notophthalmus lineages, resulting in significant autapomorphy evolution that likely began in either the late Oligocene or early Miocene.