Chelic nut
Chelichnus is a fossil footprint that was described from the Permian of Scotland in1831. This makes it the first fossil vertebrate footprint to be scientifically described. The English geologist and paleontologist William Buckland showed as early as the 1820s that turtle tracks could have been left byrunninglive turtles over a dough . The trace genus Chelichnus ("turtle trace") was established in 1850 by William Jardine . Today it is known that the producer of Chelichnus is not to be found among the turtles, but among the mammal-like reptiles (Synapsida); possibly it is the trace of a Caseiden .
Today numerous other traces from Europe and North America are ascribed to Chelichnus . The footprint always occurs within the deposits of sand dunes; the habitat of the trace producer was therefore deserts. The combination of chelichnus and dune deposits is also known as chelichnus ichnofacies. Very similar traces can be found in the much younger dune deposits of the Upper Triassic and Lower Jurassic in North and South America, which indicates that the special foot shape of the Chelichnus producer is an adaptation to locomotion on loose sand and has developed independently of one another in different groups .
Individual evidence
- ^ Richard McCrea, William AS Sarjeant, S. George Pemberton, Murray K. Gingras, James A. MacEachern: History of Ichnology: The Correspondence Between the Reverend Henry Duncan and the Reverend William Buckland and the Discovery of the First Vertebrate Footprints . In: Ichnos . 15, No. 1, 2007, ISSN 1042-0940 , pp. 5-18. doi : 10.1080 / 10420940600864670 .
- ^ A b Martin G. Lockley, Christian Meyer: Dinosaur tracks and other fossil footprints of Europe . Columbia University Press, 2000, ISBN 0-231-10710-2 , pp. 25-28, 35-38.
- ^ A b Adrian P. Hunt, Spencer G. Lucas: Permian tetrapod ichnofacies . In: Geological Society, London, Special Publications . 265, No. 1, 2006, p. 151.
