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Vendor: Fossil Soup
SKU Number: SQ5182164
Coosella rieri from the Middle Cambrian, Weeks Formation, House Range, Millard County, Utah.
Like many of the trilobites from the Weeks Formation, this is a rarely seen trilobite. This example is quite large at over 2 cm. Coosella trilobites are characterized by opisthoparian facial sutures, which is the most common suture type in trilobites. The suture runs from the front of the cephalon to the posterior margin.
Fossil size:
Length: 2.4 cm
Width: 1.5 cm
Height: 0.1 cm
Matrix size:
Length: 24.0 cm
Width: 15.0 cm
Height: 1.0 cm
Full dimensions are listed below.
Vendor: Fossil Soup
SKU Number: SQ5182164
Coosella rieri from the Middle Cambrian, Weeks Formation, House Range, Millard County, Utah.
Like many of the trilobites from the Weeks Formation, this is a rarely seen trilobite. This example is quite large at over 2 cm. Coosella trilobites are characterized by opisthoparian facial sutures, which is the most common suture type in trilobites. The suture runs from the front of the cephalon to the posterior margin.
Fossil size:
Length: 2.4 cm
Width: 1.5 cm
Height: 0.1 cm
Matrix size:
Length: 24.0 cm
Width: 15.0 cm
Height: 1.0 cm
Full dimensions are listed below.
Additional Information
This ancient arthropod was a bottom-dweller, likely a deposit feeder that moved slowly across the seafloor, sifting through the mud and sediment to find organic particles to eat. The specimen in the post capture the stunning contrast of its dark, finely textured exoskeleton against the light, reddish-brown limestone matrix. This beautiful trilobite offers a rare glimpse into a moment in time over half a billion years ago. Found in Utah's Fossil-Rich Weeks Formation This location is a Konservat-Lagerstätte, a rare fossil site preserving both hard-shelled and delicate, soft-bodied organisms. The trilobites were likely buried rapidly by a storm or high-salinity event in a shallow sub-tidal environment, perfectly preserving them for us to find today.
The Weeks Formation is located in the central House Range of western Utah. Its stratigraphic position is:
- It conformably overlies the Marjum Formation
- It is conformably overlain by the Orr Formation
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