SOFT-TISSUE PRESERVATION IN A 95 MILLION YEAR OLD MARINE LIZARD: FORM, FUNCTION, AND AQUATIC ADAPTATION

A new, and almost perfectly preserved skeleton of a Cretaceous (Cenomanian) marine lizard, tentatively referred to cf. Pontosaurus sp. (Kornhuber, 1873; Kramberger, 1892; Pierce and Caldwell, 2004), found in a quarry near Nammoura, Lebanon (Dal Sasso and Pinna, 1997; Dal Sasso and Renesto, 1999), and now housed in the Museo Civico di Storia Naturale di Milano, preserves exquisite details of the squamation as well as the tracheal system. These rare soft tissue features, in association with the skeleton and unique tail, provide important insights into a topic frequently ignored in discussions of squamate evolution (Estes et al., 1988; Norell and Gao, 1997; Pianka and Vitt, 2003), i.e., the rapid radiation and diversification of squamates (e.g., snakes, pontosaurs, dolichosaurs, aigialosaurs, and mosasaurs) into aquatic environments in the Late Mesozoic. Institutional Abbreviations—GBA, Austrian Geological Survey, Wien, Austria; MCSNT, Museo Civico di Storia Naturale, Trieste, Italy; MSNM, Museo Civico di Storia Naturale di Milano, Milano, Italy; UAMZ, University of Alberta, Museum of Zoology, Edmonton, Alberta, Canada.