Russian Trilobite Illaenus sarsi in Rare Prone Position

Description: This is an example of the unusual trilobite Illaenus sarsi. This Illaenus 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 ploughing through the substrate in search of a meal. Typically, the large cephalon is pulled under, probably as a result of the contraction of muscles as the trilobite died. This one, however, is quite prone, making for a dramatic and uncommon presentation of this unusual taxon. Notice the distinctive terrace lines of the cephalon. The trilobite has been prepared at the edge of the matrix in such a way that the terraced cephalic doublure is visible from below. The matrix has a flattened edge for easy upright display.