| Schizochroal
eyes appear of trilobites in the lower
Ordovician along
with all trilobites of Order
Phacopida, but Schizochroal are unique to Suborder Phacopina.
Because they are "crystal eyes",
they are often well preserved in trilobite fossils, and
constitute both beauty
and a
marvel of evolution. Because the lenses are typically much
small in number (less than ~ 700) and larger than the holochroal
eyes from which they ostensibly descended, they are easily
visible
to the
human
eye without
magnification. Schizochroal eye lenses were separated,
each having its own cornea. |
Phacopina
Trilobite Fossils with Schizochroal Eyes |
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| Family
Acastidae Foum
Ziguid, Morocco
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Family
Dalmanitidae Haragan
Formation, Oklahoma
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Family
Phacopidae Hamilton
Group, New York
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Family
Phacopidae
Hamilton
Group, New York
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Devonian
Order Phacopida
Family Acastidae
Devonian
Alnif, Morocco
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| Below to be converted: |
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Family
Dalmanitidae
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Superfamily
Acastoidea |
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Alnif,
Morocco |
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Family
Phacopidae |
Family
Dalmanitidae
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Family
Asteropyginae
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Silica
Shale Formation, Ohio |
Calzada
de Calatrava, Spain
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Hamilton
Group, New York
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Family
Acastidae
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Family
Phacopidae
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Family
Acastidae
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Family
Acastoidea
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Ofaten,
Morocco
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Oued
Ghris, Alnif, Morocco
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Timrhanrhart
Formation, Morocco
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Subfamily
Asteropyginae |
Subfamily
Asteropyginae |
Family
Acastidae
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Family
Phacopidae
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Alnif,
Morocco |
Moscow
Formation, New York |
Ofaten,
Morocco
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Issimour,
Alnif, Morocco
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| done: |
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Family
Dalmanitidae
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Family
Acastidae
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Family
Phacopidae
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Haragan
Formation, Oklahoma
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Foum
Ziguid, Morocco
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Hamilton
Group, New York
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