Name: Kuehneotherium praecursoris
Age: Upper Triassic - 210 Million Years Old
Formation: Upper Triassic in-fillings of Carboniferous limestone fissures
Location: Pant Quarry, Nr. Bridgend, South Glamorgan, Wales, Great Britain

Kuehneotherium is a mammaliaform genus of symmetrodont that lived during the late Triassic period and is characterized by a reversed-triangle pattern of molar cusps. It is thought to be an insectivore that could consume only soft-bodied insects such as moths. Their teeth were shaped for vertical shearing and could not crush harder prey. 

Kuehneotherium lived alongside another early mammal, Morganucodon, which had teeth that could crush harder insects such as beetles. This distinction in diet shows that early mammals adapted to have a separate feeding niche so they would not compete for food.

Kuehneotherium has tribosphenic teeth. A primitive mammalian tooth pattern that features three main cusps in the upper jaw and three main cusps in the lower jaw, along with a basin on the lower jaw

The following teeth are those presented in the Riker box. Each tooth is less than 1.0 mm in size.

Upper jaw

The three main cusps are the protocone, paracone, and metacone. The protocone is on the lingual side of the tooth, while the paracone and metacone are on the buccal side. The triangular area that includes these three cusps is called the trigon.

Lower jaw

The three main cusps are the paraconid, protoconid, and metaconid. These cusps form a trigonid, and behind the trigonid is a basin called the talonid basin. The talonid basin has three cusps: the hypoconid, hypoconulid, and entoconid. 

Tribosphenic teeth are capable of both grinding and shearing and are thought to be a key to the early success of mammals. The pattern is still present in some mammals today, such as opossums. 

Key to tooth figure:
1.Reptile
2.Cynodont
3. Eucynodont
4. Symmetrodont
5. Mammal

The synapsids were the dominant land animals in the late Paleozoic and early Mesozoic, but the only group that survived into the Cenozoic are mammals. 
Unlike other amniotes, synapsids have a single temporal fenestra, an opening low in the skull roof behind each eye orbit, leaving a bony arch beneath each. The distinctive temporal fenestra developed about 318 million years ago during the Late Carboniferous period, when synapsids and sauropsids diverged.

Mammaliform teeth, mandibles and bones have been found in a number of Carboniferous limestone quarries where fissures have been in-filled with late Triassic sands. The following images indicate the location of the quarries and an example of how the in-filled fissures appear from within the one of the quarries.

A series of volcanic eruptions buried the Cerro Cuadrado forest approximately 160 million years ago at a time when the Araucaria mirabilis conifer’s cones were reaching maturity.

Araucaria mirabilis is an extinct species of conifer from the Middle Jurassic, Cerro Cuadrado Petrified Forest, Patagonia, Argentina

Specimens are often cut and polished to reveal the true beauty of the internal structure of the cone in minute detail.

These cones were acquired at the Tucson, Mineral, Gem and Fossil show in the 1990’s from Ulrich Dernbach. After 2003 the Argentine government prevented any further export of the cones. As a result, these cones are now very sought after and will only become more rare.

These beautiful cones have become silicified by the process of mineralization. The water that percolated through the volcanic ash was absorbed into the cones who take on the color associated with the minerals that were prevalent in the ash.

Discovered in 1892 by William S. Valiant and made famous by the work of Charles Emerson Beecher, the BTB (Beecher's Trilobite Bed) is located in a small quarry outside of Rome, New York. The layer in which the stunning pyritized trilobites are found is known as the OTB (Original Trilobite Bed), and is represented by a 4cm thick layer of shale that has yielded some of the most spectacular fossils ever found. The most prominent fossil from the OTB is Triarthrus eatoni, an Upper Ordovician trilobite from the Frankfort Shale of the Lorraine Group.

The OTB is a Konservat-Lagerstätte with exceptional soft tissue preservation of antennae, appendages and occasionally egg broods preserved near the underside of the cephalon. There exist only a few sites around the world that preserve this level of detail.

The details of the quarry location were lost when Charles E. Beecher died unexpectedly in 1904. It would take another 80 years for the site to be re-discovered by 2 amateur collectors, Thomas E. Whitely and Dan Cooper. The Yale Peabody Museum became involved with the site and administered it for research projects over the next 20 years.

For the last 15+ years the quarry has been managed by Markus Martin, founder of Gold Bugs. Not only is Markus the owner of Gold Bugs, he is the recognized expert on the preparation of fossils from this site.

To understand how easy it was for the quarry to become lost from record I’ve taken a photo of part of the quarry and of a block from the OTB.

At the top of the blog figure 1. shows an excavated section of the quarry taken down to the OTB. It should be noted that a section like this takes a good weekend of backbreaking work to excavate! Figures 3. and 4. represent a block of the OTB I took from this actual section. This is a characteristic piece of the bed that is weathered and provides little indication that it is contains the 4cm layer of shale that is the OTB.

Figures 5. and 6. show the opposite side of the block displayed in figure 3. This side has been polished to reveal the now very characteristic dark line that is the base of the OTB and the coarsely undulating upper limit 4 cm above. A stark contrast to the photos in figures 3. and 4. Is it any wonder that this famous layer of shale was lost for so long!

If we take a look at figure 7. we can see the OTB in a little more detail. The thickness of the OTB is represented by the vertical line indicating a total thickness of 4 cm. What’s interesting about this polished section is that the first centimeter up from the base is slightly lighter than the rest of the OTB (You may have to look a little closer to see it). This is the most productive part of the bed, though the remaining 3 cm of shale also preserve pyritized trilobites.

We are fortunate enough to have a variety of fine examples of soft-tissue trilobites from Beecher’s on Fossil Soup thanks to it’s current caretaker - Markus Martin.

References:

Some of the material in this blog post was sourced from Wikipedia. Click this link for the Wikipedia page: Beecher’s Trilobite Bed

We’re kicking off today’s blog post by looking at an exceptional example of E. crassituberculata from the famous La Farge quarry in Paulding, Ohio. These trilobites are from the Middle Devonian, Silica Shale Formation.

The Paulding quarry was once a mecca for all fossil clubs in the Mid-West eager to collect the beautifully enrolled and sometimes prone trilobites from the blast piles.  

Unfortunately, it is no longer possible to collect from the quarry and these fossils are now only available from old collections or from a lucky find at the “Paulding County Community Fossil Garden”, where La Farge continue to support the collectors thirst for these classic Ohio trilobites.

Eldredgeops is a recently introduced genus (1990), replacing Phacops as the name for the common North American Devonian Phacopid trilobite. The change was necessary to distinguish between morphological differences observed in Phacopid trilobites on the African and European edge of the Rheic Ocean and those on the N. American edge.

Calymmene latifrons, the first Phacopid trilobite to be described, was found in Gerolstein, Germany. Unfortunately the holotype was lost and topotype material was used until a neotype specimen was designated in 2006. The neotype was designated Phacops latifrons and is now the definitive specimen for the description of Phacops. When a change in name was suggested, it was the N. American trilobite that received the new genus name as the European trilobite had been described first.

For a really good understanding of the differences between the 2 genera, follow this link: Phacops Vs Eldredgeops

The post is on The Fossil Forum and is by Gerry Kloc, dated June 8, 2014.