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    Tylosaurus kansasensis
    Late Cretaceous
    Smoky Hill Chalk, Niobrara Formation, Logan
    Co., Western Kansas, USA
    Undisputed Emperors of the high Cretaceous seas, the Mosasauridae were a family of serpentine marine reptiles, apex predators, and scourge of the many and varied ocean-dwelling creatures with which they shared the ancient waters. With a heavy, barrel-shaped body and long propulsive tail, it outlasted all rivals. The family was named for the river Meuse, near Maastricht in the Netherlands, where remains of this astonishing creature were first discovered in the late eighteenth century. Over seventy different species have been discovered around the world, however, in Antarctica, Australasia, Europe, Africa, and the Americas from north to south, ranging from 7 feet in length, to the monstrous 55-foot long Mosasaurus hoffmanni of the late Cretaceous Niobrara chalk in Kansas. This is an outstanding example of a Tylosaurus skull, perfectly preserved with superlative, fine-grained bone texture and a wonderful woody patination. It boasts a near-complete set of the robust and extremely effective-looking, recurvate teeth, with a lovely dark brown enamel. These are backed up by the curious secondary array of pterygoid (flanged) teeth on the palate. The Mosasaur had a soft skull and a jaw that could unhinge, and probably swallowed its prey whole. The still-living food would have been greatly hindered from escaping from the deadly creature's mouth by this nasty surprise waiting inside. Such jaws and dentition are a distinctive feature of Snakes, suggesting to Edward Drinker Cope that Snakes and Mosasaurs may have shared a common ancestor (in fact, they are most similar to the modern Monitor lizards). A museum-standard and highly evocative specimen, the skull measures 47 inches long, presented on an ebonized metal display stand, 23½ inches high.

    Condition Report*: Condition report available upon request.
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    Auction Info

    Auction Dates
    May, 2012
    20th Sunday
    Bids + Registered Phone Bidders: 3
    Lot Tracking Activity: N/A
    Page Views: 9,845

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