Dicranurus monstrosus Moroccan Trilobite

Dicranurus monstrosus

Trilobites Order Lichida, Family Odontopleuridae

Geological Time: Lower Devonian

Size: 55 mm

Fossil Site: Laatchana Formation deposits near Alnif, Morocco


Dicranurus monstrosusHere 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

 

 

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