chudleighensis Russian Trilobite
Size (25.4 mm = 1
inch): 60 mm long by 38 mm wide on a 73 by 54 mm matrix
Location: Asery Horizon
deposits of the Wolchow River region near Saint Petersburg, Russia
This is an example of the unusual trilobite Illaenus chudleighensis.
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 ploughing through the substrate in search of a meal.
It is also one of the less common of the genus, with this one in
a relatively prone position; most Illaenus are seen in an enrolled
position, presumably a result of post mortem contraction of muscles
in the massive cephalon.
click to enlarge