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Additional Information
Elrathia kingii is one of the most common trilobites of the Middle Cambrian, wheeler Shale formation in Utah. Its more familiar form is a compressed dark gray mineralized carapace on a mid to dark gray shale. However, the Wheeler Shale has many facies including calcareous shale, shaley limestone, mudstone and thin, flaggy limestone that create amazingly colorful contrasts of reds, yellows, browns and greens.
The rock color combinations are caused by a variety of minerals, including iron and organic carbon. The color of sedimentary rocks reflect the depositional environments, including oxygen levels, organic matter, sedimentation rate, etc. Color is also influenced by transition metals such as iron, magnesium, copper, zinc, titanium and many others. E. kingii is a medium-sized trilobite with a smooth sub-ovate carapace that is tapered towards the rear. Thorax is usually 13 segments. Pygidium has four axial rings and a long terminal piece. Posterior margin of the pygidium has a long broad medial notch.
Vendor: fossil soup - ZZ
SKU Number: SQ5388284
Rhombampyx yii trilobite from the Middle Ordovician, Meitan Formation, Zunyi, Guizhou, China.
The distinct oval/rhomboid dome where the anterior needle spine meets the head is the highly inflated glabella. It is slightly compressed but shows the distinctive bulbous shape unique to raphiophorids.
You can clearly see a thin, straight line pointing straight up from the top of the glabella. This is the base of the median snout spine.
The two elongated cheek spines can be seen on either side of the body. In life, these spines flared outward to stabilize the animal or deter predators, but post-mortem movement or burial compaction has curved it around the cephalon.
Full dimensions are listed below.