Pythons in the Eocene of Europe reveal a much older divergence of the group in sympatry with boas

Extant large constrictors, pythons and boas, have a wholly allopatric
distribution that has been interpreted largely in terms of vicariance in
Gondwana. Here we describe a stem pythonid based on complete skeletons
from the early-middle Eocene of Messel, Germany. The new species is close
in age to the divergence of Pythonidae from North American Loxocemus and
corroborates a Laurasian origin and dispersal of pythons. Remarkably, it
existed in sympatry with the stem boid Eoconstrictor. These occurrences
demonstrate that neither dispersal limitation nor strong competitive
interactions were decisive in structuring biogeographic patterns early in
the history of large, hyper-macrostomatan constrictors and exemplify the
synergy between phylogenomic and paleontological approaches in
reconstructing past distributions.