Eocryphops
sp
Trilobites
Order Phacopida, Family Phacopidae
Geological
Time: Middle Devonian
Size (25.4
mm = 1 inch): Trilobite is 22 mm long by 11 mm wide on a 43 mm by
65 mm matrix
Fossil Site:
Jorf, Morocco
Fossil Code:
12099
Price: Sold
Description:
This unusual trilobite comes from a new location known as Jorf
in Morocco, close to the site from which the polished goniatie
ammonites originate. The preservation of the exoskeleton is reminiscent
of them in terms of texture, unlike many trilobites from Morocco.
The first example I have seen was a month or so ago. Note the
mere handful of facets present in each eye. This one is a member
of the genus Eocryphops. Those cited in the literature typically
have some 2-3 times as many facets as seen here. Either this
one is an aberration or a species new to science. A reduction
in eyes was a common occurrence in phacopids, particularly in
the Devonian, with another genus being Plagiolaria. Another trilobite
from the region is a blind Gerastos (see my other
Trilobite offerings).
What is it about the environment at Jorf that allowed some trilobites
to reduce the eye facets or eliminate them altogether? While
they are thought to lived in a deep-water environment, it was
still one in the photic zone, and they are found in association
with other trilobites with more conventional eye formats. With
a surge in interest in specimens from Jorf we can only hope to
see even more unusual material coming to light.
Reference: Paleontolgische Zetschrift 2005 Vol. 79/2, pp.227-239. |
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