Unusual Illaenus schmidti Russian Trilobite

Name: Illaenus schmidti var cliens Russian trilobite

Age: Lower Ordovician

Size (25.4 mm = 1 inch): 90 mm long by 52 mm wide on a 75 by 48 mm matrix

Location: Asery Horizon deposits of the Wolchow River region near Saint Petersburg, Russia

Illaenus schmidti Russian TrilobiteThis is an example of the unusual trilobite Illaenus schmidti. Based upon the fact that the freestanding genal spines are neither as long, nor as widely extended, as some examples it is most likely an example of the variety cliens. The other variety, cardinalis has flaring, elongated genals. Some think these may have been an expression of sexual dimorphism. This is one of the 50-odd members of the genus, and known for the high profile of the cephalon which is thought to have aided the trilobite in plowing through the substrate in search of a meal. This one is presented wrapped around its matrix which has a flattened base for display from any aspect.

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