Fig. 2: Structure of soft tissues of Temnodontosaurus specimen SSN8DOR11.
From: Adaptations for stealth in the wing-like flippers of a large ichthyosaur
a, Distal tip. Note chordwise-parallel skin ornamentations. Arrowheads indicate bifurcating lines. b, Mid-distal portion of the trailing edge. Originally, each serration was strengthened by a chondroderm (arrows); however, some elements have been taphonomically displaced relative to the soft-tissue margin (arrowheads). c, Internal view of soft tissues. Topographically, the preserved matter includes (from exterior to interior): (1) phosphatized epidermis with melanophores; (2) densely packed melanosomes (arrowhead); (3) structural fibre bundles; and (4) a phosphatic crust. Arrows denote main fibre bundle directions. d, Pigment cells (arrowheads) embedded in phosphatized epidermis. Inset, melanophores with dendritic processes after demineralization (n = 3 samples). e, Transmission electron microscopy (TEM) micrograph of a melanophore containing melanosomes (n = 2 samples). f, Aggregated melanosomes (black layer) representing the taphonomically condensed epidermal–dermal interface and superficial dermis (EDISD). The phosphatic crust marks the bottom of the preserved sequence. g, FEG-SEM micrograph depicting EDISD melanosomes enveloping a chondroderm (c) (n = 5 specimens). h, Structural fibre bundle architecture. i, Leading edge (le) of SSN8DOR11. Arrows indicate principal fibre bundle directions. p (II), phalanx of digit II. Scale bars, 5 cm (a), 2 cm (b), 3 mm (i), 1 mm (c), 500 µm (h), 200 µm (d,f), 20 µm (d, inset), 10 µm (g), 2 µm (e).
