Bivariate plots of the most complete Adaffa Formation theropod tooth (SGS 0090) using CBL, CBW, and CH.

<p>Both A, CBL/CH; and B, CBW/CH tooth parameters indicate placement of SGS 0090 (green x) exclusively within the minimal scatter area (green polygon) of the sampled abelisaurid taxa, <i>Majungasaurus</i> and “<i>Indosuchus</i>”. Symbol equivalencies shown in Fig. 3.</p

Dinosaur remains from the Adaffa Formation of Saudi Arabia.

<p>Titanosaurian distal caudal vertebra (SGS 0366) in: A, anterior; B, lateral; and C posterior views. Abelisaurid teeth including: D, crown fragment (SGS 0061) with enlargement of the distal denticles; and maxillary-dentary tooth (SGS 0090) shown in distal (E) and lateral (F) views with enlargements of the distal carina and baso-apical enamel ridges.</p

Measurements of SGS 0061 and SGS 0090 used in the morphometric analyses (CBL, CBW, CH, AL are in mm).

<p>Parameters follow Smith et al. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0084041#pone.0084041-Smith3" target="_blank">[32]</a>. Abbreviations: CBL, crown base mesial-distal length; CBW, crown base labio-lingual width; CH, crown height from apex to distal enamel base; AL, apical length from medial enamel base; CBR, crown base ratio CBW/CBL; CHR, crown height ratio CH/CBL; CA, crown angle from mesial base to crown; DA, number of denticles/5 mm ( =  density) at the apical section of the distal carina; DC, distal denticle density at the mid-crown; DB, distal denticle density at the crown base; DAVG, average distal denticle density/5 mm.</p

Canonical variate analysis plot of the Adaffa Formation theropod teeth (SGS 0061, SGS 0090) using all metric parameters.

<p>SGS 0061 + SGS 0090 represented by (green x); other symbol equivalencies shown in Fig. 3. Axes 1 and 2 depict maximum discrimination in the data set.</p

Principal components analysis plot of the most complete Adaffa Formation theropod tooth (SGS 0090) using CBL, CBW, CH, and AL.

<p>SGS 0090 (green x) is placed exclusively within the minimal scatter area (green polygon) of the sampled abelisaurid taxa, <i>Majungasaurus</i> and “<i>Indosuchus</i>”. Axis/symbol equivalencies shown in Fig. 3.</p

Principal components analysis plot of the most complete Adaffa Formation theropod tooth (SGS 0090) using all metric parameters.

<p>Result derived by adding SGS 0090 (green x) to the dental morphometric matrix of Smith et al. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0084041#pone.0084041-Smith3" target="_blank">[32]</a>. Samples were organized into 10 categories representing theropod family-level clades (see legend). Component axes 1 and 2 depict maximum discrimination in the data set; minimum scatter areas for each group indicated by polygons coded by taxon/sample colour.</p