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Figure 5


Figure 5. Vertebrates from the Tytherington fissures. All vertebrate material was prepared in 10 % acetic acid following the method of Rixon (1976). (a) Severnichthys. BRSUG specimen 23730. Blackened cusp of tooth from palynomorph-bearing rock; fissure 1, x15, scale bar 500 µm. (b) Fossil charcoal. BRSUG specimen 23880. Fissure 1, x20, scale bar 250 µm. (c, d) Clevosaurus. BRSUG specimen 23731. A worn tooth, (c) occlusal and (d) view of tooth base. Found in the same palynomorph-bearing rock specimen as BRSUG specimen 23730. Fissure 1, x20, scale bar 250 µm. (e) Gyrolepis. BRSUG specimen 23735. Tooth, fissure 2, x15, scale bar 500 µm. (f, g) Unknown chondrichthyan. BRSUG specimen 23729. Unidentified fossil, possibly a shark (hybodont?) denticle, fissure 2, x15, scale bar 500 µm. (h) ‘Palaeosaurus.’ BRSUG specimen 23601. Tooth type, fissure 2, x5, scale bar 1 mm. (i) Thecodontosaurus. BRSUG specimen 23600. Tooth, fissure 2, x5, scale bar 1 mm. (j) Diphydontosaurus. BRSUG specimen 23725. Worn bone, showing corrosion, fissure 2, x10, scale bar 500 µm. (k) Glauconitic clay-mineral BRSUG 23726. Fissure 2, x20, scale bar 250 µm. (l) Ooids in aggregated cluster, BRSUG 23727. Fissure 2, x10, scale bar 500 µm. (m) Section through aggregated ooid showing concentric calcite rings (arrowed) around a haematitic core, BRSUG 23736. Fissure 2, x15, scale bar 500 µm. (n) Diphydontosaurus avonis. BRSUG specimen 23987. Part of left dentary, medial view, showing pleurodont teeth, fissure 2, x10, scale bar 500 µm. (o) Diphydontosaurus avonis. BRSUG specimen 23988, Part of left dentary in lateral view, showing flaking of outer bone (arrowed) caused by sub-aerial exposure, fissure 2, x10, scale bar 500 µm. (p) Diphydontosaurus avonis, BRSUG specimen 23989. Anterior part of right dentary in medial view, showing wear due to post mortem transport, fissure 2, x10, scale bar 500 µm. (q) Planocephalosaurus robinsonae. BRSUG 23755. Part of right maxilla, lateral view, from palynomorph-bearing deposit, fissure 2, x5, scale bar 1 mm. (r) Steinkern of ‘Rhaetic’ gastropod. BRSUG 23728. Fissure 2, x20, scale bar 250 µm. (s) Diphydontosaurus avonis. BRSUG specimen 23990. Part of left maxilla, lateral view showing wear due to post-mortem transport, fissure 2, x15, scale bar 500 µm. (t, u) Clevosaurus. BRSUG specimen 23700. Left dentary, (t) lateral and (u) medial view, fissure 2, x2.5, scale bar 2 mm. (v) Unidentified Lepidosaur. BRSUG specimen 23737. Limb bone with metallic sulphide coating (arrowed), fissure 2, x15, scale bar 500 µm. (w, x) Pholidophorus. BRSUG specimen 23738. White-coloured scale found in the rock that produced the holotype of Diphydontosaurus avonis, (w) internal and (x) external view, fissure 2, x15, scale bar 500 µm. (y) Euestheria minuta. BRSUG specimen 23640. Fissure 4, x5, scale bar 1 mm. (z) Collection of bones in a typical assemblage of white, yellow and brown bones (and bone fragments) from the rock that produced the type specimens of D. avonis, WB, white bones and YB, yellow bones of Diphydontosaurus. BRSUG specimen 23739. Fissure 2, x5, scale bar 1 mm. (aa, bb) Lepidosaur ‘B’ of Whiteside (D. I. Whiteside, unpub. Ph.D. thesis, Univ. Bristol, 1984). BRSUG specimen 23670. Anterior of blackened left maxilla of sphenodontian related to Diphydontosaurus and Gephyrosaurus in (aa) lateral and (bb) medial view, fissure 12, x10, scale bar 500 µm. (cc) Euestheria minuta var. brodeiana. BRSUG specimen 23641. Two individuals, fissure 12, x5, scale bar 1 mm. (dd) Pelecymala sp. BRSUG specimen 23897. Part of left dentary in lateral view. The tooth-wear facets are caused by orthal shear rather than propalinal movement found in the similar Clevosaurus latidens Fraser, 1993, fissure 14, x3.5, scale bar 1 mm. (ee) Clevosaurus. BRSUG specimen 23890. Part of left dentary of a juvenile in lateral view, fissure 14, x10, scale bar 500 µm. (ff) Planocephalosaurus. BRSUG specimen 23891. Scanning electron micrograph; the posterior view of the right premaxilla of a juvenile showing (?replacement) pits at the base of the teeth, fissure 14, x25, scale bar 200 µm. (gg) Clevosaurus. BRSUG specimen 23691. Lateral view of toothed part of blackened right dentary, fissure 13, x10, scale bar 500 µm. (hh) Pholidophorus. BRSUG specimen 23692. External view of brown coloured scale showing growth rings (arrowed), fissure 13, x10, scale bar 500 µm. (ii, jj) Pholidophorus. BRSUG specimen 23690. (ii) External and (jj) internal view of brown coloured scale, fissure 13, x15, scale bar 500 µm. (kk) Conodont. BRSUG 23732. Scanning electron micrograph of reworked Carboniferous conodont, probably Bisphathodus, fissure 14, x25, scale bar 200 µm. (ll) Gyrolepis. BRSUG 23733. Scanning electron micrograph of white tooth found in the same rock with Planocephalosaurus, Tricuspisaurus and Pelecymala preserved in the same manner, fissure 14, x25, scale bar 200 µm. (mm, nn) Diphydontosaurus. BRSUG specimen 23892. Part of blackened right dentary showing alternating sized-teeth, (mm) medial and (nn) lateral view, fissure 16, x15, scale bar 500 µm. (oo, pp) Tricuspisaurus. BRSUG specimen 23893. Teeth, coloured grey, in (oo) lateral and (pp) occlusal view, fissure 14, x10, scale bar 500 µm. (qq) Planocephalosaurus. BRSUG specimen 23894. Part of right maxilla brown coloured in lateral view, fissure 14, x10, scale bar 500 µm. (rr) Planocephalosaurus. BRSUG specimen 23895. Left grey coloured dentary in lateral view, fissure 14, x5, scale bar 1 mm. (ss) Part of rock hand specimen BRSUG 23896 showing possible associated whitish/grey-coloured Clevosaurus bones including a maxilla ‘M’ and a dentary ‘D’, fissure 16, x4, scale bar 2 mm.