US DOLLAR
EURO
AUSTRALIAN DOLLAR
CANADIAN DOLLAR
POUND STERLING
Product Description
ID
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Chirotherium sp.
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FOUND
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Bernburg, Germany
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AGE
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MIDDLE TRIASSIC (PELSONIAN):
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SIZE
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17.25" x 14"" overall, footprint is 7" long,
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CONDITION
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TYPICAL REPAIR TO CRACKS FROM
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NOTE
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THE RAREST FOSSIL TRACKWAY
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INCLUDES STAND - Actual Item - One Only
Comes with a certificate of |
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Displaying prominent large impressions of a walking Chirotherium, this is an EXTREMELY RARE fossilized trackway of both, hand and foot impressions made by the same reptile. The specimen is the actual tracks that had become preserved in stone, not the outwardly negative impressions of such. This plate comes from the original collector and is a spectacular remnant of the gait of these large Triassic reptiles once walking in search of food. The site from which this trackway comes from has been scientifically studied and published revealing it was once the edge of the low tide zone of an inner ancient sea. Parts of the stone at this site show tracks from breeding horseshoe crabs that were sought out as tasty meals by these Chirotherium beasts picking them off at the waters edge. This fossil not only shows exquisitely preserved hand and foot prints, it also offers evidence of the feeding behavior of Chirotherium as well as the nature of what environment the trackway fossils originated from. A TRUE MUSEUM-CLASS SPECIMEN WORTHY OF THE MOST IMPRESSIVE COLLECTIONS OF RARE FOSSIL TRACKWAYS AND FOSSILS SHOWING PREHISTORIC PREDATOR BEHAVIOR. EXTREMELY SCARCE with EXPECTED REPAIR BUT NO FABRICATION. Prints have been only highlighted with reversible sealer. Back of rock plate reinforced for stability when displayed.
Chirotherium, also known as Cheirotherium (‘hand-beast’), is the name of a Triassic trace fossil consisting of five-fingered (pentadactyle) footprints and whole tracks. These look, by coincidence, remarkably like the hands of apes, humans, and bears, with the outermost toe having evolved to extend out to the side like a thumb, although probably only functioning to provide a firmer grip in mud.
The creatures who made the footprints and tracks were probably pseudosuchian archosaurs related to the ancestors of the crocodiles. They likely belonged to either prestosuchidae or rauisuchidae groups, which were both large carnivores with semi-erect gaits.
Chirotherium tracks were first found in 1834 in Lower Triassic sandstone (Buntsandstein) in Thuringia, Germany, dating from about 243 million years ago (mya). Similar discoveries were made in England in 1838. They were found before dinosaurs were known and were initially believed to have been made by a bear or ape, which walked with its feet crossed. This proposal was necessary to explain the toe on the outside. The tracks were also proposed to be from a marsupial. These fossil tracks have now been found on North America, Argentina, North Africa, Europe, and China.
British paleontologist Richard Owen suggested in 1842, that the tracks were made by a labyrinthodont amphibian. Over the following years, new discoveries of archosaurian reptiles indicated that Chirotherium tracks were made by a pseudosuchian. The print’s resemblance to mammals was only superficial; in reality, an external (lateral) ‘thumb’ was commonplace among Triassic archosaurs.
In 1965, the skeleton of an animal probably closely related to the trackmaker of Chirotherium was found, called Ticinosuchus. It had the external toe on its hind feet but not on its front feet and was possibly a more derived descendant, whose gait did not require a stabilizing front toe. Footprints of different size and proportions occurring together on one and the same bedding plane probably reflect a gender difference (sexual dimorphism) within the trackmaker species.
Chirotherium trackways have been found in German sandstones that were likely deposited on flood plains. During the Middle Triassic, much of Central Europe was covered by a shallow epicontinental sea (the so-called Muschelkalk Sea). In one location, Chirotherium trackways were found alongside those of early horseshoe crabs. The horseshoe crabs were likely breeding along the intertidal zone while the Chirotherium trackmaker preyed on them during low tide.
This specimen comes from published fossil trackway mega-site that revealed these were made by Chirotheriums walking to along a coastal low tide zone edge in search of an abundance of breeding horseshoe crabs to feed on. The abstract of the paper discussing the nature and origin of this specimen is as follows:
Newly excavated Middle Triassic reptile Chirotherium, Rhynchosauroides and horseshoe crab Kouphichnium imprints from the uppermost Pelsonian megatracksite Bernburg, Germany (Central Europe) represent different behavioural trackways. The Chirotherium/Rhynchosauroides/Kouphichnium track assemblage of the lower intertidal carbonate flats is dominated by well-known horseshoe crab tracks of various subaquatic benthic movements which were all left on mud-cracked biolaminites in reproduction coastal zones. Most abundant reptile Rhynchosauroides trackways (50 % of reptile tracks) are oriented more beach-parallel (to Rhenish Massif Island) as a result of food searching along the intertidal seismic-influenced coast (16 slickensided biolaminate layers within 2 m biolaminates due to Alpine fold belt and Germanic intracratonic Basin tectonics), most probably for feeding on high abundant horseshoe crab eggs resulting from mating events in the lower intertidal. Large basal archosaur predators (?Ticinosuchus) produced large Chirotherium trackways (25 % of reptile tracks) which are represented in the new material with exceptional unusual trackways (slipping and side steps), but in directions to and from the beach to the Rhenish Massif main land, indicating predation on small reptiles. Finally, medium-sized Chirotherium trackways of subadult animals are present (25 % of reptile tracks). One trackway has a unique “feeding place” area, indicating the unexpected either predation, playing or feeding of a basal archosaur on a horseshoe crab. The horseshoe crab migrations from the North Tethys onto the extended mating intertidal mud flat beaches of the Germanic Basin, and recently known even into Chinese lagoons migrating limulid populations of different horseshoe crab species must have caused a global and seasonal food chain reaction, whereas Macrocnemus reptiles (Rhynchosauroides trackmaker) might have fed only on Millions of their eggs.
By Bernd Hutschenreuther
