DOI: 10.5061/dryad.j67f87m
title: Data from: Sauropod teeth from the Middle Jurassic of Madagascar, and the oldest record of Titanosauriformes

description: 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.
description: S1 - 3D model of MSNM
 V5801Specimen MSNM V5801
 comes from the Sakaraha Formation (Isalo IIIb subunit), which is Bathonian
 in age (Middle Jurassic). It has been collected in 2001, in association
 with MSNM V5802 and V5803, near the Tsinjorano village school (Majunga
 Province, NW Madagascar). It was lying near two theropod teeth and two
 fragmentary sauropod long bones, almost completely powdered by weathering
 (G. Pasini, pers. com. 2016). This specimen is attributed to morphotype J2
 and included in taxon A, which represents a taxon more derived than
 Mamenchisauridae but not belonging to Titanosauriformes and Diplodocoidea.
 This 3D model has been generated with photogrammetry processing and
 merging 34 photos together; an object with about 180000 faces has been
 obtained. Description in the main text.3D model of MSNM
 V5801.pdfS2 - 3D model of MSNM
 V6216Specimen MSNM V6216
 comes from the Sakaraha Formation (Isalo IIIb subunit), which is Bathonian
 in age (Middle Jurassic). It has been collected in 2003, isolated from
 other fossils. A peculiar character of this specimen is the twisting of
 the crown, where it approaches the crown tip. This character has been
 considered to be a synapomorphy of Brachiosauridae (D’Emic 2012). It is
 attributed to morphotype J3 and included in taxon B, which represents a
 basal Brachiosauridae or basal Titanosauriformes. This 3D model has been
 generated with photogrammetry processing and merging 71 photos together,
 divided in two groups, to obtain an object with about 795000 faces.
 Description in the main text.3D model of MSNM
 V6216.pdfS3 - 3D model of MSNM
 V6217Specimen MSNM V6217
 comes from the Sakaraha Formation (Isalo IIIb subunit), which is Bathonian
 in age (Middle Jurassic). It has been collected in 2003, isolated from
 other fossils. It is distinguished by a unique elongate, spindle–like
 shape, and by a transverse section that remains subcircular up to
 one-third of the crown height. This specimen is the only representative of
 morphotype J8, taxon D, which should belong to Diplodocoidea
 (Dicraeosauridae?) or Titanosauria. MSNM V6217 might represent a new
 taxon, maybe a basal member of Diplodocoidea, and the oldest fossil record
 of the clade in Africa. This 3D model has been generated with
 photogrammetry processing and merging 50 photos together, divided in two
 groups, to obtain an object with about 1000000 faces. Description in the
 main text.3D model of MSNM
 V6217.pdf