Fossil for Sale!
Dinosaur, Pterosaur fossils
for sale in auction.

For bid is an ichnofossil specimen containing a reptile trackway on Coconino Sandstone from the Colorado Plateau region of Northern Arizona. This specimen dates from the Early Permian period of the Upper Paleozoic Era, and is approximately 280 million years old. Coconino Sandstone is the fossilized remnants of massive eolian dune deposits that once covered much the Colorado Plateau and Grand Canyon regions of present day northern Arizona. During the Permian these regions probably looked similar to a Sahara-like desert environment covered with massive sand seas and mountainous dunes of shifting sand. Depending on how much iron oxide it is stained with, Coconino Sandstone ranges in color from dark red to a less common white.

Inhabiting this dry environment were several species of mammal-like and lizard-like reptiles, along with a number of different arthropods; mostly represented by spider and scorpion-like insects. It is amazing that in this type of environment these creatures have left such nicely preserved fossil tracks. It is believed the reason they are so well preserved is that the tracks were left when the top layer of sand was damp from moisture, perhaps after a morning dew or light rain. The tracks were then quickly covered by a fine layer of sand preserving them. It has been my personal observation and purely speculative, that perhaps the tracks were preserved best at certain times of the year;  maybe during some of the cooler months. I have noticed that tracks are often encountered on fossil bearing slabs surrounded above and below with thick layers of non-fossil bearing rock. I have seen this pattern repeated over and over representing layers as much as 30 feet thick. Maybe these "barren" layers were deposited during hotter and drier months of the year when the conditions were not as favorable for ichnofossil preservation. The mammal-like reptile tracks found on these deposits have been given the name of Cheilichnus (Laoporus is synonymus) and is comprised of three different names based on the size of the tracks. No fossilized remains have been found of these creatures, therefore it is unknown exactly what they looked like. Based on the tracks Cheilichnus may have appeared as a reptile walking around like a small modern day mammal. Try and picture a rodent or small dog walking around with the body of a lizard! Unlike modern reptiles that walk with their legs splayed out far from their bodies; Cheilichnus's body was located high above the ground with its legs located directly below its body. For this reason along with a possible stubby tail, is why a tail drag is seldom seen along with the fossil tracks. It is interesting to note that Cheilichnus tracks of the Coconino coincide with similar tracks found in the Lyons Formation of Colorado. Both formations are of the same approximate age and appear to have been formed under the same conditions. These ichnospecies apparently have also been identified in the Cornberger Sandstein of Germany and the Corncockle and Locharbriggs Sandstone Formations of Scottland. Tracks from a lizard-like reptile called Dolichopodichnus, are also occasionally encountered in the Coconino. Its tracks appear as long slender claw marks left in the sand and seem similar to the tracks of modern lizards. It appears that Dolichopodichnus was capable of bi-pedal motion and its tracks are most often seen running.

At its widest points this piece measures approximately 17-1/2 inches long by 9-1/2 inches wide and nearly 1/2 of an inch thick. It is the upper or natural cast half of the fossil tracks. The slab contains two reptile trackways and one from an unknown type of arthropod. Bounding along the left side of the slab are a small set of Dolichopodichnus tracks. They are about 1/2 of an inch wide and because of the speed at which it was traveling not much detail was left. In the same area is a nice one inch wide insect trackway that crosses the entire length of the slab. I am not sure what type of insect made these tracks, perhaps some type of beetle. The trackway shows more detail in person than in the pictures. The other reptile trackway appear to be from Cheilichnus bucklandi, the smallest of the Cheilichnus sp. in the Coconino. They measure about 1/2 an inch wide and show great detail for their tiny size. This is a chance to get a nice piece detailing different types of reptile and insect tracks.

Please click on the below links with articles on Coconino ichno's that have some descriptive content about these types of Permian tracks:

 http://www2.nature.nps.gov/geology/paleontology/pub/fossil_conference_6/hunt.htm

 http://www.janrasmussen.com/Coconino.htm

This is a real trace fossil and not a man made cast or reproduction. 

Please e-mail me with any questions or for additional pictures.

Thanks and good luck!