Pentanogmius evolutus
    Late Cretaceous
    Smoky Hill Chalk, Niobrara Formation, Logan Co., Western Kansas, USA

    A wide variety of fish were to be found in the warm shallow waters of the Western Interior Seaway that covered much of today's North America towards the end of the Cretaceous period, 85 million years ago. The Pentanogmius was one of the most distinctive of these fish, a plethodid Tselfatiiform with a large, pronounced bony "sail" on its back. Not a great deal is known of the species, however, for even amongst the abundant and well-preserved fossils of the Niobrara Chalk, their remains are extremely scarce. It is supposed that they preyed primarily on oysters and clams, partly on the basis of heavy jaws, which would have made short work of crushing the shells. The mouth boasts distinctive palatine bones, perfectly visible in the present fossil; covered in tiny pits, in life each pit would have held a tiny tooth to create a bristling carpet of death for any unsuspecting prey that strayed too near the fish's gaping maw. The rest of this superb specimen exhibits similar fine quality, with excellent three-dimensionality and detail throughout, from the bony head, via robust vertebrae and pectoral fin, to the mass of hefty tail bones. There are even numerous isolated scales preserved amidst the ribs, and the long, trailing bones of the spiny dorsal fin are wonderfully evocative of the creature's original shape. Finely preserved and with a warm, dark brown patina, it is presented in a harmoniously creamy colored, sand-textured pho-matrix, framed in stained wood, 17½ x 36½ inches overall.

    Estimate: $4,500 - $5,500.

    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. 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. All lots are sold "AS IS" under the Terms & Conditions of Auction.

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    Auction Info

    Auction Dates
    May, 2012
    20th Sunday
    Bids + Registered Phone Bidders: 0
    Lot Tracking Activity: N/A
    Page Views: 823

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