Paradoxides Trilobite and Rare Forfexicaris Arthropod Association

Description: Presented is an unusual association plate from the Barrandian of the Czech Republic. The Paradoxides is mid-sized and in good condition, though missing its free cheeks. The more intriguing specimen is the Forfexicaris sp. It’s an unusual and odd arthropod. I have never encountered one before, and obviously, never one from all of the hundreds of Czech trilobites that have passed over my desk.

Forfexicaris valida was an egg-shaped nektonic predatory arthropod also known from the Lower Cambrian Maotianshan shale Lagerstätte about 1.5 centimetres long. This creature bears a superficial resemblance to ostracod crustaceans, though, F. valida is not considered to be an ostracod, nor even a crustacean due to its leg morphology. Like its relative, Occacaris oviformis, F. valida also had a pair of "great appendages," though, it did not have paired spines. Unlike O. oviformis, F. valida's trunk did not extend beyond its carapace.

There are more that 1300 described species of Barrandian trilobites. An amazing statistic when you consider the area collected is only a few hundred square miles. Bohemia is the historical name given to the area of central Czech Republic where these species are found. Barrandian trilobites refer to the trilobite fauna found here. The term comes from the seminal work done by the J. Barrnade (1799-1883) who spent over half his life describing these trilobites and helping establish the science of paleontology. He himself described over 300 species. Bohemian trilobites are found in the Middle, and Upper Cambrian, Ordovician, Silurian and Devonian Periods. They have been studied and collected since the mid 1700's. Their quality of preservation, variety and scientific importance has made them most collectable ever since.