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Chinlestegophis is a diminutive Late Triassic Stereospondyli that has been interpreted as a putative stem caecilian, a living group of legless burrowing amphibians. If Chinlestegophis is indeed both an advanced stereospondyl and a relative of caecilians, this means that stereospondyls (in the form of caecilians) survived to the present day; historically the group was thought to have gone extinct by the early Cretaceous. Chinlestegophis jenkinsi, the type and only species, is known from two partial skulls discovered in the Chinle Formation in Colorado.
Other workers have disputed the interpretation of Chinlestegophis as a stem caecilian on various grounds. For example, Marjanović & Laurin (2019) note that the original study reported only a Bayesian consensus and a majority-rule consensus tree of the main data matrix, and while both support the claimed caecilian affinities of Chinlestegophis jenkinsi, the strict parsimony consensus tree does not, given that it is compatible with lissamphibian monophyly (indeed, this topology is found in some of the most parsimonious trees); those workers generally favor and recover support for a monophyletic origin of lissamphibians from Lepospondyli. Criticism of the use of the majority-rule consensus has also been published by Serra Silva & Wilkinson (2021). The use of a modified version of the Pardo et al. matrix by Daza et al. (2020) and Schoch et al. (2020) recovered a single origin of all lissamphibians from dissorophoids, consistent with the historic "temnospondyl hypothesis"; further analysis in the description of the unequivocal Late Triassic gymnophionomorph Funcusvermis gilmorei also recovered the traditional "temnospondyl hypothesis." The characters that have been used to support affinities of Chinlestegophis have also been criticized. No other studies to date have independently supported the hypothesis of relationships proposed by Pardo et al.
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