The Borioteiioidea (Polyglyphanodontia) is a group of lizards commonly found in Cretaceous
Laurasian deposits and is considered as the sister group of Teiidae. While the Asian
record comprises several well-preserved skulls and skeletons, other Laurasian occurrences
are generally known from disarticulated skull material and isolated teeth. Additionally,
the Gondwanan record is rare, with only one species described so far, Bicuspidon hogreli,
from the Ifezouane Formation, Kem Kem Beds of Morocco. Given their wide geographic
distribution, several biogeographic hypotheses were suggested to explain the temporal
and spatial distribution of borioteiioids. In this study, we report the first record
of a borioteiioid from the Lower Cretaceous of South America. The specimen was unearthed
from Aptian deposits of the Quirico Formation (Sanfranciscana Basin), Brazil, and
consists of both anterior portions of dentaries. Among other characteristics, the
material has transversally wide mid-posterior teeth with two distinct cusps (labial
and lingual), as typically seen in species of the genus Bicuspidon. It also exhibits
additional features, such first mental foramen facing anteriorly and the remaining
ones forming a line in the lateral portion of the dentary, anterior symphyseal process
extending from the anterior margin of the symphysis, and symphysis bearing an oval-shaped
and thick process. These characteristics allowed us to erect a new species of Borioteiioidea,
Cryptobicuspidon pachysymphysealis gen. et sp. nov. Cryptobicuspidon pachysymphysealis
is one of the oldest records of Borioteiioidea known so far and suggests that Polyglyphanodontini
borioteiioids originated in Gondwana with a posterior dispersal to North America and
Europe during the Late Cretaceous.(c) 2023 Elsevier Ltd. All rights reserved.
