FIGURE 1. Three topological hypotheses for the evolution of the pectoral girdle elements from the basal neodiapsid condition to basal eosauropterygian condition are depicted in two-dimensions. Large black dot - glenoid; Small black dot - coracoid foramen; A- anterior margin of the coracoid; M-medial margin of the coracoid; CL - clavicle; INCL - interclavicle; SC - scapula; ST - sternum.
FIGURE 2. Topological homologies underlying the proposed muscle reconstructions, using as a model the nothosaur Ceresiosaurus calcagnii PIMUZ T3983 (left) and the basal plesiosaur Meyerasaurus victor cast of SMNS12478 (right).
FIGURE 3. Muscle reconstruction of the pectoral girdle musculature of the Eosauropterygia using data from the extant phylogenetic bracket, the fossil record and developmental patterns.
FIGURE 4. Humeral insertions in a basal neodiapsid, Nothosaurus and Cryptoclidus .
FIGURE 5. M. subcoracoscapularis. Reconstruction for Neusticosaurus 1 in anterior view, 2 in ventral view, 3 in lateral view, 4 in fleshed-out muscle reconstruction and 5 complete skeletal reconstruction in lateral view. Reconstruction for Ceresiosaurus 6 in anterior view, 7 in ventral view, 8 in lateral view, 9 fleshed-out muscle reconstruction and 10 complete skeletal reconstruction in lateral view. Reconstruction for Rhomaleosaurus 11 in anterior view, 12 in ventral view, 13 in lateral view, 14 fleshed-out muscle reconstruction and 15 complete skeletal reconstruction in lateral view.
FIGURE 6. M. scapulodeltoideus (= m. deltoideus scapularis, = m. dorsalis scapulae, = m. teres major. Reconstruction for Neusticosaurus 1 in anterior view, 2 in ventral view, 3 in lateral view, 4 fleshed-out muscle reconstruction and 5 complete skeletal reconstruction in lateral view. Reconstruction for Ceresiosaurus 6 in anterior view, 7 in ventral view, 8 in lateral view, 9 fleshed-out muscle reconstruction 10 complete skeletal reconstruction in lateral view. Reconstruction for Rhomaleosaurus and 11 in anterior view, 12 in ventral view, 13 in lateral view, 14 fleshed-out muscle reconstruction and 15 complete skeletal reconstruction in lateral view.
FIGURE 7. M. clavodeltoideus (= m. deltoideus clavicularis, = m. deltoideus). Reconstruction for Neusticosaurus 1 in anterior view, 2 in ventral view, 3 in lateral view, 4 fleshed-out muscle reconstruction and 5 complete skeletal reconstruction in lateral view. Reconstruction for Ceresiosaurus 6 in anterior view, 7 in ventral view, 8 in lateral view, 9 fleshed-out muscle reconstruction and 10 complete skeletal reconstruction in lateral view. Reconstruction for Rhomaleosaurus 11 in anterior view, 12 in ventral view, 13 in lateral view, 14 fleshed-out muscle reconstruction and 15 complete skeletal reconstruction in lateral view.
FIGURE 8. M. scapulohumeralis (= m. scapulohumeralis caudalis, = m. scapulohumeralis posterior). Reconstruction for Neusticosaurus 1 in anterior view, 2 in ventral view, 3 in lateral view, 4 fleshed-out muscle reconstruction and 5 complete skeletal reconstruction in lateral view. Reconstruction for Ceresiosaurus 6 in anterior view, 7 in ventral view, 8 in lateral view, 9 fleshed-out muscle reconstruction and 10 complete skeletal reconstruction in lateral view. Reconstruction for Rhomaleosaurus 11 in anterior view, 12 in ventral view, 13 in lateral view, 14 fleshed-out muscle reconstruction and 15 complete skeletal reconstruction in lateral view.
FIGURE 9. M. supracoracoideus (= m. coracobrachialis superior, = m. coracobrachialis brevis dorsalis). Reconstruction for Neusticosaurus 1 in anterior view, 2 in ventral view, 3 in lateral view, 4 fleshed-out muscle reconstruction and 5 complete skeletal reconstruction in lateral view. Reconstruction for Ceresiosaurus 6 in anterior view, 7 in ventral view, 8 in lateral view, 9 fleshed-out muscle reconstruction and 10 complete skeletal reconstruction in lateral view. Reconstruction for Rhomaleosaurus 11 in anterior view, 12 in ventral view, 13 in lateral view, 14 fleshed-out muscle reconstruction and 15 complete skeletal reconstruction in lateral view.
FIGURE 10. M. coracobrachialis longus and brevis. Reconstruction for Neusticosaurus 1 in anterior view, 2 in ventral view, 3 in lateral view, 4 fleshed-out muscle reconstruction and 5 complete skeletal reconstruction in lateral view. Reconstruction for Ceresiosaurus 6 in anterior view, 7 in ventral view, 8 in lateral view, 9 fleshed-out muscle reconstruction and 10 complete skeletal reconstruction in lateral view. Reconstruction for Rhomaleosaurus 11 in anterior view, 12 in ventral view, 13 in lateral view, 14 fleshed-out muscle reconstruction and 15 complete skeletal reconstruction in lateral view.
FIGURE 11. M. latissimus dorsi. Reconstruction for Neusticosaurus 1 in anterior view, 2 in ventral view, 3 in lateral view, 4 fleshed-out muscle reconstruction and 5 complete skeletal reconstruction in lateral view. Reconstruction for Ceresiosaurus 6 in anterior view, 7 in ventral view, 8 in lateral view, 9 fleshed-out muscle reconstruction and 10 complete skeletal reconstruction in lateral view. Reconstruction for Rhomaleosaurus 11 in anterior view, 12 in ventral view, 13 in lateral view, 14 fleshed-out muscle reconstruction and 15 complete skeletal reconstruction in lateral view.
FIGURE 12. M. triceps brachii. Reconstruction for Neusticosaurus 1 in ventral view, 2 in lateral view, 3 fleshed-out muscle reconstruction and 4 complete skeletal reconstruction in lateral view. Reconstruction for Ceresiosaurus 5 in ventral view, 6 in lateral view, 7 fleshed-out muscle reconstruction and 8 complete skeletal reconstruction in lateral view. Reconstruction for Rhomaleosaurus 9 in ventral view, 10 in lateral view, 11 fleshed-out muscle reconstruction and 12 complete skeletal reconstruction in lateral view.
FIGURE 13. M. trapezius . Reconstruction for Neusticosaurus 1 in anterior view, 2 in ventral view, 3 in lateral view, 4 fleshed-out muscle reconstruction and 5 complete skeletal reconstruction in lateral view. Reconstruction for Ceresiosaurus 6 in anterior view, 7 in ventral view, 8 in lateral view, 9 fleshed-out muscle reconstruction 10 complete skeletal reconstruction in lateral view. Reconstruction for Rhomaleosaurus 11 in anterior view, 12 in ventral view, 13 in lateral view, 14 fleshed-out muscle reconstruction and 15 complete skeletal reconstruction in lateral view.
FIGURE 14. M. serratus. Reconstruction for Neusticosaurus 1 in anterior view, 2 in ventral view, 3 in lateral view (orange for Level II inference), 4 fleshed-out muscle reconstruction and 5 complete skeletal reconstruction in lateral view. Reconstruction for Ceresiosaurus 6 in anterior view, 7 in ventral view, 8 in lateral view, 9 fleshed-out muscle reconstruction and 10 complete skeletal reconstruction in lateral view. Reconstruction for Rhomaleosaurus 11 in anterior view, 12 in ventral view, 13 in lateral view, 14 fleshed-out muscle reconstruction and 15 complete skeletal reconstruction in lateral view.
FIGURE 15. M. levator scapulae. Reconstruction for Neusticosaurus 1 in anterior view, 2 in ventral view, 3 in lateral view, 4 fleshed-out muscle reconstruction and 5 complete skeletal reconstruction in lateral view. Reconstruction for Ceresiosaurus 6 in anterior view, 7 in ventral view, 8 in lateral view, 9 fleshed-out muscle reconstruction and 10 complete skeletal reconstruction in lateral view. Reconstruction for Rhomaleosaurus 11 in anterior view, 12 in ventral view, 13 in lateral view, 14 fleshed-out muscle reconstruction and 15 complete skeletal reconstruction in lateral view.
FIGURE 16. M. costocoracoideus. Reconstruction for Neusticosaurus 1 in anterior view, 2 in ventral view, 3 in lateral view, 4 fleshed-out muscle reconstruction and 5 complete skeletal reconstruction in lateral view. Reconstruction for Ceresiosaurus 6 in anterior view, 7 in ventral view, 8 in lateral view, 9 fleshed-out muscle reconstruction and 10 complete skeletal reconstruction in lateral view. Reconstruction for Rhomaleosaurus 11 in anterior view, 12 in ventral view, 13 in lateral view, 14 fleshed-out muscle reconstruction and 15 complete skeletal reconstruction in lateral view.
FIGURE 17. Comparison of pectoral girdle musculature reconstruction between this study and previously published reconstructions.
