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    Trilobite Fossil
    Isotelus brachycephalus
    Upper Ordovician
    Dillsboro Formation
    Oldenburg, Indiana, USA

    Trilobites are an extinct variety of ancient marine arthropods which flourished during the Paleozoic Era before dying out in the mass extinction at the end of the Permian some 250 million years ago. While all gone at that point, Trilobites thrived in the oceans of the prehistoric world for an incredible 270 million years. These odd-looking and popular creatures had the first complex vision center of any organism. An evolutionary trait of Trilobites was gigantism which impacted the Asaphidia to which Isotelus belonged.

    The term "museum quality" is much too often overused, but this truly spectacular Trilobite specimen is no doubt fitting of that moniker. The very large Isotelus exhibits virtually no visible restoration and is an amazing example of the much sought after variety. The specimen features a lovely dark caramel-colored carapace which contrasts nicely with the blue-gray matrix in which it rests. Specimens of this quality are not typically seen in private collections, and any others of this grade would likely be found in a museum.

    This massive top notch specimen is nicely inflated and shows relatively minimal cracking of the fossilized shell, at least compared with many other similar fossils, which often exhibit a large amount of fracturing. There is some debate as to the proper species to assign to this variety as it obviously presents much like an Isotelus maximus. The bottom line is that Isotelus brachycephalus may in actuality just be a variant of the maximus which, of course, is a very well-known and accepted variety. The Isotelus genus happens to be the state fossil of Ohio which is known for producing some of the best specimens ever found. The fossil itself measures approximately 9 inches (22.9 cm) long and 6.25 inches (15.9 cm) wide, with the width from tip to tip of the genal spines about 7 inches (17.8 cm).
    Overall Measurements: 12.40 x 11.02 x 2.95 inches (31.50 x 28.00 x 7.50 cm)

    [Scale: 1 inch, with mark at 1 cm]

    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
    March, 2021
    19th Friday
    Bids + Registered Phone Bidders: 1
    Lot Tracking Activity: N/A
    Page Views: 1,478

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    25% on the first $300,000 (minimum $49), plus 20% of any amount between $300,000 and $3,000,000, plus 12.5% of any amount over $3,000,000 per lot.

    Sold on Mar 19, 2021 for: Sign-in or Join (free & quick)
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