domingo, 30 de março de 2008

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Ultra rare only known specimen giant pterodactyl skull with associated mandible and vertebra form possible undescribe species. Santana Formation. Ceara, Brazil. Lower Cretaceous Period: 110 million years ago

Of all the richest fossil-bearing deposits ever known, Brazil's Santana Formation is ranked among the world's greatest. Santana fossils are known for not only their extreme diversity but more importantly, for the nature of their breath-taking preservation - considered by scientists to include the finest examples of fossils in existence. The formation provides an amazing window into the paleobiota of a prehistoric world from the Lower Cretaceous, 110 million years ago. The Santana fossils of Brazil were first recorded in the year 1828 by two natural historians, Dr. J. B. von Spix and Dr. C. F. P. von Martius, commissioned by the king of Bavaria.

To this day, they are still being studied with many new discoveries coming to light. Our recent purchase of a 70+ year old private European collection of vertebrate Santana fossils has provided us with numerous spectacular quality specimens that go well beyond the quality and completeness of anything we have seen in either private hands or in museum collections. While these specimens were originally collected in the 1930's before the ban enacted in 1942, they had remained in their raw state "as collected" up until only recently, whereby they were prepared utilizing the most modern laboratory techniques and equipment hence their remarkable state of display.

In comparison, the definitive illustrated work on these fossils, written by curator John G. Maisey titled "Santana Fossils", is illustrated with numerous prized specimens owned by the American Museum of Natural History (AMNH) in New York. The specimens we acquired exceed or match the quality of the finest specimens shown from the American Museum in this publication. In this collection were several extremely rare and scientifically important pterosaur fossils.
Pterosaur remains from the Santana Formation are amongst the rarest of all fossils found there. The first Santana pterosaur fossils were only published as recently as 1971. Maisey writes about the pterosaur fossils from Santana, "With regard to the excellent quality of fossil preservation and to the increasing number of pterosaur fossils being collected, the Santana Formation of the Chapada do Araripe has become one of the most important pterosaur localities in the world."

Later in the same chapter he writes, "It is worthwhile to point out that for the morphological study of pterosaurs, the sediments of the Santana Formation are surely one of the most important in the world because the preservation of the material is the best ever reported." The wealth of recent discoveries from this area has brought forth a host of new and very diverse pterosaur fauna.

The scientific value of the Santana pterosaur fossils is immeasurable with extraordinary new discoveries coming to light at the present moment. Remains of many new species have and continue to be found in these deposits but these specimens are reserved for scientific study and export by an authorized institution only. No fossil have been allowed to be legally exported for the private market for several decades. The only hopes for a private collector to legally own any of the rare pterosaur remains from the Santana Formation is to acquire a specimen from an old private collection but these too, are extremely rare in numbers, rarer than recent finds.

Mere words cannot fully emphasize the extreme rarity, priceless value and scientific importance of this specimen. The majority of pterodactyl remains from this formation are of the Anhanguerid family of pterosaurs. Recent discoveries have revealed a new second family of pterosaurs from this formation that include bizarre assemblage of pterosaurs of which this specimen likely belongs.

These are characterized by an enormous crest, a very large nasopreorbital fenestra and the lack of teeth. In general, pterosaur fossilized bones are extremely rare. When alive, the bones were thin and partially filled with air making them extremely delicate by design. Because of this, very seldom do the bones survive as fossils. Isolated remains are found on rare occasion but associated and especially articulated discoveries such as this fossil, are an extreme scarcity and important scientifically. Finding a discovery such as this is a "once-in-several-lifetimes" chance!
This is a COMPLETE skull with ultra rare anatomy intact AND a still articulated original mandible and cervical vertebra.

In John Maisey's book titled "Santana Fossils", he cites the prevalence of fake, composite and enhanced fossils from this formation that are on the market. The local artisans at the sites produce a wide variety of artificially created fossils - some horribly obvious yet some, extremely convincing out of carefully matched composite pieces.

These composite examples are very convincing because they are made up of all real pieces but not necessarily of the same species! Often, missing parts are carved or sculpted from a mixture of plaster, rock dust and epoxy and then painted to disguise the work. A number of these handcrafted "fossils" have in the past, and continue to, make it into the mainstream fossil market.

Describing a variety of techniques and types of fakes, Maisey even shows photographs of some fakes for reference to illustrate the breadth, creativity and skill of some of these workers. He also addresses the prevalence of fake insect and other rare fossils within the text. With all Brazilian fossils, collectors should approach prospective purchases with caution for not only the legality of the specimen but also, for accurate disclosure by a qualified and experienced preparator of any artificial enhancement to the specimen.

PALEO DIRECT guarantees every Santana Formation specimen we offer to be AUTHENTIC and "as described" with a written unlimited lifetime guarantee / certificate of its authenticity and data sheet. Rarely do fossils possess the preservation of those found in Brazil's Santana Formation located on the Araripe Plateau.

The magnificent fossils include a vast selection of fish, insects and plants along with rare occurrences of the remains of pterosaurs, dinosaurs, frogs, turtles, crocodiles and miscellaneous marine invertebrates. Santana fossils are predominantly made up of two kinds of fossils which are classified as two different strata - the earlier Crato members which are found in shales and thin limestone layers and the later Romualdo members which are found in round limestone concretions.

The lower or older Crato member strata occur as fossils in laminated limestones that were deposited on an undisturbed lakebed. These types include small fishes and a diverse fauna of insects and other animals suggesting a dry open terrestrial environment. A frog has been found in the Crato deposits along with the impression of a feather and pterosaur remains. Romualdo member fossils include a wide variety of fish, plants and rare occurrences of reptiles such as crocodiles, turtles, dinosaurs and pterosaurs.

Most impressive are the fact that these concretionary fossils are preserved in a full three dimensional perspective and when prepared with the utmost care and skill, reveal features and anatomy that are akin to the animal being alive. The exact dating of these two members remains enigmatic although the Crato members are known to pre-date the Romualdo members. It is possible that both are within the same time zone of the Lower Cretaceous. Despite the long period of time these fossils have been known, much work remains in the study and determination of dating and the full breadth of the flora and fauna from the Santana Formation of Brazil.

The Pterosaur was a flying reptile (commonly referred to as Pterodactyl "wing finger") of the order Pterosauria. They existed from the late Triassic to the Cretaceous Periods (228 - 65 million years ago) with the earlier Triassic species having long, fully toothed jaws and long tails. The later forms had a stump for a tail, no teeth and a jaw more like a beak than the elongated jaw of the earlier species. At least 60 genera of pterosaurs have been found with sizes ranging from a sparrow to monsters with wingspans in excess of 40 feet! The wings were thin membranes of skin, similar to the wings of bats, and extended along the sides of the body.

They were attached to the extraordinarily long fourth finger of each arm. The bones were hollow and had openings at each end. Unlike typical reptiles, pterosaurs had a breastbone that was developed for the attachment of flight muscles and a brain that was more developed than comparable dinosaurs of similar sizes. There is no fossil evidence of feathers. Most researchers now believe that pterosaurs were adapted for active flight, not just gliding as was earlier believed.

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