Trilobite - Cornuproetus cornutus
SKU:
ITEM # TRILO-Morocco-0023
$300.00
$300.00
Devonian - 375 mya
Alnif, Morocco
ITEM # TRILO-Morocco-0023
Excellently-prepared free-floating example of Cornuproetus cornutus, a proetid trilobite from the Devonian of Morocco. Cornuproetus had holochroal eyes that looked laterally over the seafloor, which may have been typical of benthic-dwelling trilobites.
Proetida is an order of trilobite that lived from the Ordovician to the Permian. It was the last order of trilobite to go extinct, finally dying out in the Permian extinction.
These typically small trilobites resemble those of the order Ptychopariida, from which the new order Proetida was only recently separated in 1975 by Fortey and Owens. Like the order Phacopida the proetids have exoskeletons that sometime have pits or small tubercles, especially on the glabella (middle portion of the head). Because of their resemblance to the Ptychopariida in some features, the proetids are included in the subclass Librostoma.
Unlike some trilobites of the order Phacopida, whose eyes are schizochroal, the proetids have the more common holochroal eyes. These eyes are characterized by close packing of biconvex lenses beneath a single corneal layer that covers all of the lenses. Each lens is generally hexagonal in outline and in direct contact with the others. They range in number from one to more than 15,000 per eye. Eyes are usually large, and because the individual lenses are hard to make out, they look smooth and sometimes bead-like.
The thorax of proetids was made up of anywhere between 8-22 segments, but most commonly 10. Many also have genial spines coming off either side of the head, though in some they are blunted. These two features can aid in distinguishing proetids from some trilobites in the order Phacopida, to which they can be very similar.
This trilobite is 3-dimensionally preserved and wonderfully articulated. It is nicely outstretched and exhibits superb detail. Both free cheeks are present and tightly attached. The close-set eyes are easily seen and the long, sweeping genal spines are beautifully displayed. The genal spines extend way past the pygidium of the trilobite! Even the small granules on the glabella are quite evident. The almost-black trilobite contrasts with the light-colored matrix in exceptional fashion. It is well positioned on the rounded plate of limestone. This is a very aesthetic specimen of Cornuproetus with gorgeous genal spines.
This specimen measures approximately 2 inches long on a matrix measuring 2 inches by 4 inches.
Alnif, Morocco
ITEM # TRILO-Morocco-0023
Excellently-prepared free-floating example of Cornuproetus cornutus, a proetid trilobite from the Devonian of Morocco. Cornuproetus had holochroal eyes that looked laterally over the seafloor, which may have been typical of benthic-dwelling trilobites.
Proetida is an order of trilobite that lived from the Ordovician to the Permian. It was the last order of trilobite to go extinct, finally dying out in the Permian extinction.
These typically small trilobites resemble those of the order Ptychopariida, from which the new order Proetida was only recently separated in 1975 by Fortey and Owens. Like the order Phacopida the proetids have exoskeletons that sometime have pits or small tubercles, especially on the glabella (middle portion of the head). Because of their resemblance to the Ptychopariida in some features, the proetids are included in the subclass Librostoma.
Unlike some trilobites of the order Phacopida, whose eyes are schizochroal, the proetids have the more common holochroal eyes. These eyes are characterized by close packing of biconvex lenses beneath a single corneal layer that covers all of the lenses. Each lens is generally hexagonal in outline and in direct contact with the others. They range in number from one to more than 15,000 per eye. Eyes are usually large, and because the individual lenses are hard to make out, they look smooth and sometimes bead-like.
The thorax of proetids was made up of anywhere between 8-22 segments, but most commonly 10. Many also have genial spines coming off either side of the head, though in some they are blunted. These two features can aid in distinguishing proetids from some trilobites in the order Phacopida, to which they can be very similar.
This trilobite is 3-dimensionally preserved and wonderfully articulated. It is nicely outstretched and exhibits superb detail. Both free cheeks are present and tightly attached. The close-set eyes are easily seen and the long, sweeping genal spines are beautifully displayed. The genal spines extend way past the pygidium of the trilobite! Even the small granules on the glabella are quite evident. The almost-black trilobite contrasts with the light-colored matrix in exceptional fashion. It is well positioned on the rounded plate of limestone. This is a very aesthetic specimen of Cornuproetus with gorgeous genal spines.
This specimen measures approximately 2 inches long on a matrix measuring 2 inches by 4 inches.
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