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| Boipeba tayasuensis Fachini, Onary, Palci, Lee, Bronzati & Hsiou, 2020 Reconstruction by Jorge Blanco. |
Highlights:
• Boipeba tayasuensis is the oldest fossil blind snake from the Late Cretaceous of Brazil
• A new phylogenetic analysis places the taxon within living typhlopoids
• Boipeba is estimated to be ∼1 m in length, larger than any living blind snake
• The small body size of extant blind snakes is due to subsequent miniaturization
Summary
Blind snakes (Scolecophidia) are minute cryptic snakes that diverged at the base of the evolutionary radiation of modern snakes. They have a scant fossil record, which dates back to the Upper Paleocene-Lower Eocene (∼56 Ma); this late appearance conflicts with molecular evidence, which suggests a much older origin for the group (during the Mesozoic: 160–125 Ma). Here we report a typhlopoid blind snake from the Late Cretaceous of Brazil, Boipeba tayasuensis gen. et sp. nov., which extends the scolecophidian fossil record into the Mesozoic and reduces the fossil gap predicted by molecular data. The new species is estimated to have been over 1 m long, much larger than typical modern scolecophidians (<30 cm). This finding sheds light on the early evolution of blind snakes, supports the hypothesis of a Gondwanan origin for the Typhlopoidea, and indicates that early scolecophidians had large body size, and only later underwent miniaturization.
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| Holotype of Boipeba tayasuensis (A) MPMA 16-0008-08, isolated precloacal vertebra in (upper row) anterior, posterior, and lateral views, respectively, and (lower row) dorsal, and ventral views, respectively. (B) Geographical and geological map showing the type locality where the fossil material was recovered. Abbreviations: cn., condyle; ct., cotyle; ns., neural spine; ptz., postzygapophysis; ppz., prezygapophyseal accessory processes; pz., prezygapophysis.; sf., subcentral foramina; sy., synapophysis; zs., zygosphene. |
Systematic Palaeontology
Squamata Oppel, 1811
Ophidia Brongniart, 1800
Scolecophidia Duméril and Bibron, 1844
Boipeba tayasuensis gen. et sp. nov.
Etymology: Generic epithet comes from the combination of the Brazilian native language Tupi-Guarani, “boi” meaning snake, and “peba” meaning flattened, in reference to the shape of the vertebrae. The species epithet “tayasuensis” derives from the type locality where the fossil was found, Taiaçu municipality, São Paulo, Brazil.
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| Life Reconstruction of Boipeba tayasuensis This large Cretaceous blind snake inhabited the arid palaeoenviroment of the Bauru Basin, Brazil, alongside titanosaur sauropods, theropods, and terrestrial crocodiles such as Montealtosuchus (Mesoeucrocodylia, Peirosauridae). The latter was found in the same outcrop as Boipeba. Reconstruction by Jorge Blanco. |
Thiago Schineider Fachini, Silvio Onary, Alessandro Palci, Michael S.Y. Lee, Mario Bronzati and Annie Schmaltz Hsiou. 2020. Cretaceous Blind Snake from Brazil Fills Major Gap in Snake Evolution. iScience. 23(12): 101834. DOI: 10.1016/j.isci.2020.101834
