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The highest species richness and ecological diversity of extant squamates are in the tropics. Both their taxic richness and functional traits are predictably correlated to environmental factors, and the utility of these measures in the squamate fossil record is an emergent tool for paleoenvironmental reconstruction. Ongoing field research in the early Miocene (approx. 20–19 Mya) Tinderet sequence of western Kenya has produced a diverse record of squamates which provides environmental data for hominoid-bearing localities. The record consists of chamaeleonid, agamid, varanid, and amphisbaenid lizards as well as snake lineages including pythonids, colubroids, elapoids, and a newly discovered taxon sharing unique vertebral apomorphies with extant tropical South American Anilius scytale. Combined with additional fossils from the Eocene of North Africa, the new Tinderet taxon demonstrates an unambiguous past record of an extant neotropical snake lineage in Africa and falsifies previous vicariance hypotheses to explain the biogeographic histories of basal divisions within snakes. Recent stable isotopic and phytolith studies of Early to Middle Miocene eastern African fossil localities have indicated heterogenous environments, including C4 grasses and wood- to scrubland, associated with vertebrate faunas. The composition of squamate faunas is generally consistent with these reconstructions, with the new taxon providing precise evidence for precipitation. Comparing climate parameters of habitats for Anilius and other extant ecological analogues equivalent to those reconstructed for the eastern African Early Miocene indicates annual precipitation between 1500–2500 mm/year, consistent with wet tropical seasonal forests and rain forests.