Pseudobasilicus
lawrowi
Class
Trilobita, Order Asaphida,
Family Asaphidae
Geological
Time: Ordovician
Size: 80
mm
Fossil
Site: Asery level, St. Petersburg region, Wolchow river, Russia
|  Coming
from the Middle Ordovician uppermost Asery Level deposits near Saint
Petersburg, Russia, this is an example of the rare Asaphid trilobite,
Pseudobasilicus. What use did the pancake-like profile serve? Here
are two possibilties: 1.
The broad profile would have allowed it to set atop a fine silty
bottom, much like snowshoes; 2.
The low profile would have allowed it to conceal itself from both
predators and prey, with only its upraised eyes showing, much like
today's flounders and stingrays.
Also see: Russian
Trilobites Gallery | |
