 Here
is one of the more sought after trilobites of the Order Lichida,
Family
Odontopleuridae known as Dicranurus monstrosus. This particular
example is quite large at 55 mm in length from the dramatic
cephalon to the
wonderful pleural spines, and has a "wingspan" of 2.6
inches at the genal spines. Notice that the librigenae are tightly
attached,
a sign of a well-articulated specimen. It is found in the Lower
Devonian Laatchana Formation deposits near Alnif, Morocco. It is
quite prone,
and dominates its 2.7 inch by 2.9 inch bed of matrix. To me, the
most impressive features are the dramatically retorted occipital
spines,
looking like ram's horns. In all, there are EIGHTEEN freestanding
spines present, making for an impressive display piece. To what
purpose
could this spiny exoskeleton have been evolved? The answer is simple
-- DEFENSE!! Fish had recently evolved jaws, and in the never ending
arms race between predator and prey, Dicranurus' amswer was a spectacular
defensive array of spines. A substantial amount of prep time goes
into a dramatic specimen such as this.
Also
see: Moroccan Trilobites |
