Fig. 4 in Growth dynamics and body size evolution of South American long-necked chelid turtles: A bone histology approach

Fig. 4. Stylopodial bone histology of chelid turtle Hydromedusa tectifera Cope, 1869; Recent, La Plata, Buenos Aires province, Argentina. A. MLPR-6474, humerus: dorsolateral (A1) and ventral (A2) areas. B. MLPR-6474, femur: ventral (B1) and dorsal (B2) areas. C. MLPR-6291, humerus: dorsal (C1) and ventral (C2) areas. D. MLPR-6291, femur: lateral (D1) and ventrolateral (D2) areas; annuli, yellow A; zones, green Z. E. MLPR-6411, humerus: dorsal (E1) and ventral (E2) areas. F. MLPR-6411, femur: lateral areas (F1, F2). Arrowheads in E2 and F2 indicate lines of arrested growth. Photographs under normal light (B1, B2, D1, E1, F2), under polarized light (E2), under polarized light with lambda compensator (A1, A2, C1, C2, D2, F1). Abbreviations: LVC, simple longitudinal vascular canals; PFB, parallel-fibered bone; RS, resorption cavities; SF, Sharpey's fibers.