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    Xiphactinus audax
    Upper Cretaceous, Santonian stage
    Upper Smoky Hill Chalk, Niobara Formation, Logan Co, Kansas
    The name Xiphactinus means "sword-ray" in Latin, referring to the long pectoral fins, but the common name of "bulldog fish" comes from the distinctive upturned jaw and sharp fang-like teeth. They were a large aggressive bony fish with a thick boned skull and a mouth full of sharp piercing teeth and reached lengths of up to eighteen feet. Their deadly nature has been communicated to us over those millions of years by numerous specimens found with whole fish in their stomachs: one famous example contains a six foot-long ichthyodectid in its gut, whose death throes on being swallowed whole most probably caused the larger creature's death

    Shaped like a modern tarpon (to which they were not related), the Xiphactinus was distinguished by the heavy bony head and long, thick body, characteristics perfectly represented in this superb specimen from the abundant chalk deposits of the Niobara Formation in Kansas. The detail of preservation, texture and three-dimensionality to the skull is simply remarkable, and the vicious black teeth protrude, some over 2 inches long, bristling with menace to complete the creature's fearsome look. The rest of the skeleton displays first-class preservation and preparation, all the more remarkable given the instability of the matrix in which these fossils are found; it is necessary to collect them using the painstaking plaster slab method, whereby the bones are cleaned in the field, a frame constructed around the fossil, and plaster poured over it. After the plaster has set, the slab is dug under and loosened, then carefully turned over. This exposes the underside of the fossil which is then painstakingly prepared in the laboratory for exhibit.

    The present specimen is composed of two separate creatures, carefully matched for size and scientific accuracy, and over 98% complete, with next to no reconstruction or repositioning. Displayed in a natural death pose, the jaws have been opened to showcase its fine teeth which are original. The fossil itself measures 14½ feet in length in the plaster slab, prepared to duplicate the original matrix in color and texture, in a dark-stained wooden frame 15 x 3½ feet. It is of a significant and robust size for this species, and makes for an extremely impressive, museum-quality display.

    Condition Report*: Condition report available upon request.
    *Heritage Auctions strives to provide as much information as possible but encourages in-person inspection by bidders. Statements regarding the condition of objects are only for general guidance and should not be relied upon as complete statements of fact, and do not constitute a representation, warranty or assumption of liability by Heritage. Some condition issues may not be noted in the condition report but are apparent in the provided photos which are considered part of the condition report. Please note that we do not de-frame lots estimated at $1,000 or less and may not be able to provide additional details for lots valued under $500. Heritage does not guarantee the condition of frames and shall not be liable for any damage/scratches to frames, glass/acrylic coverings, original boxes, display accessories, or art that has slipped in frames. All lots are sold "AS IS" under the Terms & Conditions of Auction.

    Auction Info

    Auction Dates
    June, 2011
    12th Sunday
    Bids + Registered Phone Bidders: 1
    Lot Tracking Activity: N/A
    Page Views: 3,997

    Buyer's Premium per Lot:
    19.5% of the successful bid (minimum $14) per lot.

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