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Fig. 7 in Xenoxylon synecology and palaeoclimatic implications for the Mesozoic of Eurasia

Fig. 7. Diversity index (DI = GD/N, where GD is the number of genera associated with Xenoxylon, and N the number of occurrences) for each time period. Abbreviations: LT, Late Triassic; EMJ, Early to Middle Jurassic; LJEK, Late Jurassic to Early Cretaceous; LK, Late Cretaceous.

Fig. 1 in First Mesozoic record of the stingray Myliobatis wurnoensis from Mali and a phylogenetic analysis of Myliobatidae incorporating dental characters

Fig. 1. Map of Mali indicating three localities discovered in the 1999 CNRST−SUNY expedition. Boundary between the Illummeden and Tauodeni basins in northern Mali is outlined in light gray. Mali−8 marks localities yielding fossils of Myliobatidae. Dark Gray marks exposed basement rocks in the Adrar des Iforas Mountains; white marks Proterozoic structure that connected the two light gray basin periodically during the Cretaceous– Paleogene.

Fig. 6 in First Mesozoic record of the stingray Myliobatis wurnoensis from Mali and a phylogenetic analysis of Myliobatidae incorporating dental characters

Fig. 6. Phylogenetic relationships and stratigraphic distribution of Myliobatidae. Epochs are not drawn to scale.

Fig. 3. The fossil stingray Myliobatis wurnoensis White, 1934 in First Mesozoic record of the stingray Myliobatis wurnoensis from Mali and a phylogenetic analysis of Myliobatidae incorporating dental characters

Fig. 3. The fossil stingray Myliobatis wurnoensis White, 1934 from Maastrichtian of Mali. A, B. Partial upper dental plates. A. CNRST−SUNY−5 in posterior (A1), occlusal (A2), and basal (A3) views. B. CNRST−SUNY−37 in posterior (B1), occlusal (B2), and basal (B3) views. C. Partial lower dental plate, CNRST− SUNY−3 in occlusal (C1) and basal (C2) views. Anterior is to top of page for all images except A1 and B1, which are in posterior view. Scale bars 10 mm.

Fig. 2 in First Mesozoic record of the stingray Myliobatis wurnoensis from Mali and a phylogenetic analysis of Myliobatidae incorporating dental characters

Fig. 2. Composite stratigraphic sections of localities Mali−7, −8, and −10. Relative stratigraphic positions of index fossils and inferred depositional settings supporting age of Myliobatis wurnoensis (Mali−8). Index fossils from Mali−7, −8, and −10. Lower gray line is the inferred KT boundary in this section and the upper gray line is the inferred position of the Paleocene–Eocene boundary in this section. Abbreviations: CG, conglomerate; LS, limestone; MS, shale; SS, sandstone.

Fig. 5 in First Mesozoic record of the stingray Myliobatis wurnoensis from Mali and a phylogenetic analysis of Myliobatidae incorporating dental characters

Fig. 5. Summary of unambiguous character transformations across Myliobatidae (node−B) that were optimized on all most parsimonious trees. Black boxes have a CI = 1.0 and white boxes have a lower CI value. Bold face denotes extinct taxa.

Fig. 8 in First Mesozoic record of the stingray Myliobatis wurnoensis from Mali and a phylogenetic analysis of Myliobatidae incorporating dental characters

Fig. 8. Comparative extinct taxa of Myliobatiformes; known ages mapped onto Fig. 6. A. Hypolophites myliobatoides Stromer, 1910, NHM P18781; A1, occlusal view, anterior to top; A2, lateral view, anterior to left; A3, root view, anterior to top. B. Brachyrhizodus wichitaensis Romer, 1942, NHM P89095; B1, occlusal view; anterior undetermined; B2, root view; anterior undetermined. C. Apocopodon sericius, NHM P24670, C1, occlusal view, anterior to top; C2, lateral view, anterior to left; C3, root view, anterior to top. D. Igdabatis sigmodon, TMM 45892−1; D1, occlusal view, anterior to top; D2, posterior view; D3, root view, anterior to bottom; D4, lateral view, anterior to left. E. Myliobatis striatus, NHM P.66859; E1, occlusal view, anterior to top; E2, root view, anterior to top; E3, posterior view; E4, lateral view, anterior to left. F. Aetobatus arcuatus, SMNH 12656−3; F1, occlusal view, anterior to top; F2, root view, anterior to top; F3, anterior view; F4, lateral view, anterior to left. Scale bars 10 mm.

Fig. 4 in First Mesozoic record of the stingray Myliobatis wurnoensis from Mali and a phylogenetic analysis of Myliobatidae incorporating dental characters

Fig. 4. Strict consensus of eight most parsimonious trees (MPT). A. Tree from full analysis with Myliobatidae condensed as single terminal taxon in gray box labeled "B". B. Expanded Myliobatidae portion of tree, which is identical on all eight MPTs. TL = 141, CI = 0.6312, HI = 0.3688, RI = 0.8844, RC = 0.5583. Bold face in B denotes extinct taxa.

Fig. 7 in First Mesozoic record of the stingray Myliobatis wurnoensis from Mali and a phylogenetic analysis of Myliobatidae incorporating dental characters

Fig. 7. Comparative extant taxa of Myliobatidae. A, B, D. Articulated jaws and tooth rows. C. Disarticulated jaws and articulated tooth rows. E–G. Articulated tooth rows. A. Raja sp., AMNH 92321b, in labial view. B. Dasyatis sp., FMNH 15625, in labial view. C. Rhinoptera quadriloba (LeSueur, 1817), FMNH 82986, in occlusal view. D. Myliobatis californica Gill, 1865, MCZ 424, in lingual view. E. Mobula hypostoma (Bancroft, 1831), AMNH 44124, in occlusal view, photograph (E1), line drawing (E2); F. Mobula rochebruni (Vaillant, 1879), FMNH 38450, in occlusal view, photograph (F1), line drawing (F2). G. Manta hamiltoni (Walbaum, 1792), FMNH 41385, in occlusal view, photograph (G1), line drawing (G2). H. Aetobatus narinari (Euphrasen, 1790), FMNH 10985, in labial view.

Fig. 7 in Size-shape relationships in the Mesozoic planispiral ammonites

Fig. 7. Plot of W/D versus U/D for the whole large sample (gray points), n = 1222. Three samples are selected to show the almost invariable relative umbilical width along significant variation of relative width of whorl section. White squares: Poecilomorphus cycloides (Middle Jurassic) modified from Sturani (1971: pl. 8); black circles: Quenstedtoceras lamberti (Middle Jurassic) modified from Callomon (1985: fig. 5b); and white triangles: Dactylioceras clevelandicum (Early Jurassic) modified from Howarth (1973: pls. 3, 4).

Fig. 8 in Size-shape relationships in the Mesozoic planispiral ammonites

Fig. 8. ADA−model simulated ammonites (as explained in text) showing the distribution of morphotypes in the reduced morphologic space RM1. All ammonites are scaled to nearly equal size. Extreme morphotypes (out of the constrained morphospace CM1, see Fig. 5A) not known within the Mesozoic Ammonoidea are shown side−by−side with known morphotypes for comparison. Bold broken line is the main trend H2 = 0.3D.

Fig. 5. A in Size-shape relationships in the Mesozoic planispiral ammonites

Fig. 5. A. Reduced morphospace RM1. Plot of individual measurements (gray points, N = 1222) and mean values for the 201 species studied classified by morphotypes. The theoretical iso−U/D curves are explained in text. The gray trapezoid−like area is delimited by curves as explained in text. The bold broken curve shows the main trend H1/D = 0.3/(H2/H1). The two thinner curves [H1/D = 0.5/(H2/H1) and H1/D = 0.1/(H2/H1)] delimit the constrained empirical morphospace CM1, the portion of RM1 realised or occupied by Mesozoic ammonoids. B. Reduced morphospace RM2 with plots of individual measurements (N = 1222) in gray points, and mean values of each one of the 201 species studied. The general trend is represented by two straight lines as described in the text.

Fig. 6. A in Size-shape relationships in the Mesozoic planispiral ammonites

Fig. 6. A. Plot of all individual measurements (n = 1222) of H2/D versus D showing relatively low variation in the Mesozoic Ammonoidea. The main trend H2/D = 0.3 is almost equal to the average <h2> = 0.303. B. Comparison of estimations of D versus actual measurements through the ontogeny of selected specimens (see Appendix 1 for details of material).</h2>

Fig. 3. A in Size-shape relationships in the Mesozoic planispiral ammonites

Fig. 3. A. Representation of the log−spiral and the associated ellipse representing the whorl section. B. Geometric equivalences between variables of the log−spiral and classical variables defined in Fig. 2.

Fig. 4 in Size-shape relationships in the Mesozoic planispiral ammonites

Fig. 4. Correlation between actual and estimated (Equation 1) values of U/D for all the ammonites studied (N = 1222; gray points) and mean values for each species classified by morphotypes. The line corresponding to (U/D)obs = (U/D)pred is shown for comparison.

Fig. 2 in Size-shape relationships in the Mesozoic planispiral ammonites

Fig. 2. Dimensions measured in coiled and uncoiled ammonites. Note the transposition between H1 and H2 from coiled (A) to uncoiled (C) ammonites, passing through the identity between H1 and H2 in the singular case (B).

Fig. 1 in Size-shape relationships in the Mesozoic planispiral ammonites

Fig. 1. Representativity of the studied sample in time and shape diversity. A. Number of species considered for each subdivision of the Mesozoic. B. Number of species for each morphotype as defined in text. Some species include individuals belonging to different morphotypes of the adopted classification.

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Fig. 8. A in Docodonts from the British Mesozoic

Fig. 8. A.?Peraiocynodon inexpectatus, labial part of the upper right molar BMNH M 45240, in labial (A1) and lingual (A2) views. B. The same reconstructed upper right molar BMNH M 45240, in posterior (B1) and occlusal (B2) views. C. Lingualpart of the right upper molar of Docodon sp., DORCM GS 983, in occlusal view. D. Lingual part of the docodont indet., left upper molar DORCM GS 1084, in occlusal view. E. Upper left P3/ BMNH M 51814, docodont indet., in labial (E1) and lingual (E2) views.

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Fig. 9 in Docodonts from the British Mesozoic

Fig. 9. Suggested relationships of the docodont genera based on lower molars. 1. Transverse widening of molars; formation of transverse crests. 2. Development of an incipient pseudo−talonid (anterior). 3. Reduction of mesio−lingual cusp; development of the real talonid (posterior); folding enamel. 4. Straight anterior crest. 5. Development of mesio−lingual cusp, of pseudo−talonid. 6. Folding of the enamel. 7. Vertical furrows. 8. Enlargment of disto−labialcusp. 9. Tendency to fuse lingual cusps together and labial cusps together.