Data from: Sauropod teeth from the Middle Jurassic of Madagascar, and the oldest record of Titanosauriformes

Here we describe 31 fossil teeth, deposited in the paleontological
collections of the Museo di Storia Naturale di Milano (MSNM), that come
from the inland portion of the Mahajanga Basin, NW Madagascar, namely from
the Sakahara Formation (classically known as Isalo IIIb subunit), which is
dated back to the Middle Jurassic Bathonian stage. Based on detailed
morphological characters, the eight morphotypes recognised herein are
tentatively referred to four sauropod taxa: Archaeodontosaurus descouensi,
‘Bothriospondylus madagascariensis’, Lapparentosaurus madagascariensis,
and an indeterminate specialised eusauropod, which may represent a new
species, and the first evidence of a Bathonian diplodocoid in Madagascar.
The identification of the teeth is corroborated by comparative examination
of morphometric data. In this paper we provide evidence that
Titanosauriformes were present in the Bathonian, on the basis of seven
specimens referable to this clade. We also discuss in detail some dental
characters that support the existence of a clear niche partitioning
between the above mentioned taxa, that co–existed in the Malagasy Middle
Jurassic terrestrial ecosystem. We finally hypothesise, for the first
time, a direct correlation between the pattern drawn on the tooth crown by
the enamel wrinkles and the feeding ecology of sauropod dinosaurs. The
enamel wrinkles likely played a structural function: coarse wrinkles were
associated to a diet composed mainly by hard foodstuff, whereas fainter
wrinkles, which appeared in more derived morphologies, were associated to
a diet composed by softer foodstuff.