Transformations in the osteoderm patterns of advanced neosuchians, shown in cross-sections of the trunks of Bernissartia fagesii, Susisuchus anatoceps, Isisfordia duncani, and Crocodylus porosus. Bernissartia fagesii, an advanced neosuchian, has a biserial paravertebral shield, in which there are two rows of paravertebral osteoderms over the back. Susisuchus anatoceps, another advanced neosuchian, has a tetraserial paravertebral shield in which two rows of paravertebral osteoderms have segmented into four. Isisfordia duncani, a basal eusuchian, also has a tetraserial paravertebral shield. Crocodylus porosus, the modern saltwater crocodile, has numerous smaller osteoderms over its back. The segmentation of the paravertebral shield over time allowed for greater trunk flexibility in eusuchians. 
Based on figure 5 of "The origin of modern crocodyliforms: new evidence from the Cretaceous of Australia" by Steven W. Salisbury, Ralph E. Molnar, Eberhard Frey, and Paul M.A. Willis. Proceedings of the Royal Society B 7 (273): 2439-2448.