Trilobite Order Lichida

The Lichida trilobites are thought to have evolved from either Order Corynexochida or Order Redlichiida. While spines are widespread among many trilobite orders and species, the Lichida trilobites win the prize for the most elaborate, ornate,

Trilobite Taxonomy	Trilobite Phylogeny
Phylum Arthropoda Subphylum Chelicerata or Subphylum Schizoramia * Superclass Arachnomorpha * Class Trilobita Order Agnostida Order Redlichiida Order Corynexochida Order Phacopida Order Lichida Order Proetida Order Harpetida Order Ptychopariida Order Asaphida Order Odontopleurida Order Nectaspida Trilobite Relatives	o Arthropoda `--o Trilobita |?-Agnostida |?-Eodiscina `--+--o Redlichiida | |--Olenellina | `--Redlichiina |--Corynexochida |--Phacopida |--Lichida |--Odontopleurida `--o Librostoma |--Proetida |--Harpetida |--Ptychopariida `--Asaphida
* Different taxonomies are found, most recently with trilobites contained in Superclass Arachnomorpha in Subphylum Schizoramia.

and possibly intimidating spines. The development of spines is commonly accepted as defense adaptation to ward off predators. An alternate hypotheses for the adaptive origin of trilobite spines is to use like snowshoes on a silty seafloor.

The 1997 Treatise defines Order Lichida as comprising Superfamilies Lichoidea, Odontopleuroidea, and Dameselloidea. While the science remains unsettled, another taxonomy is gaining favor that erects Order Odontopleurida from Superfamilies Odontopleuroidea and Dameselloidea.

 

 

 

 

 

 

		Superfamily Lichoidea
Phylum Arthropoda Subphylum Chelicerata Class Trilobita Order Lichida Superfamily Lichoidea Family Lichakephalidae Family Lichidae Superfamily Odontopleuroidea Family Odontopleuridae Superfamily Dameselloidea Family Damesellidae
		Arctinurus boltoni Family Lichidae Rochester Shale Formation, Middleport, New York	Hoplolichas furcifer Order Lichida Superfamily Lichoidea Family Lichidae Ordovician Wolchow River, Russia
Acanthopyge consanguinea Lichida Family Lichidae Lower Devonian Bois d' Arc Formation Coal County, Oklahoma	Hoplolichas plautini Lichida Family Lichidae Ordovician Wolchow River, Russia	Hoplolichas tricuspidatus Lichida Family Lichidae Ordovician Wolchow river, Russia	Metoplolichas verrucosus Family Lichidae Metoplolichas verrucosus Wolchow River, Russia
Acanthopyge consanguinea Bug X Lichida, Family Lichidae Lower Devonian Haragan Formation Coal County, Oklahoma
Family Odontopleuridae = Order Odontopleurida
Dicranurus monstrosus Family Odontopleuridae Lower Devonian Alnif, Morocco	Dicranurus hamatus elegantus Family Odontopleuridae Lower Devonian Haragan Formation Coal County, Oklahoma	Proceratocephala Family Odontopleuridae Lower Ordovician Lower Ktaoua Formation, Morocco	Laethoprusia sp Family Odontopleuridae Lower Devonian Haragan Formation Coal County, Oklahoma
Leonaspis roemeri Family Odontopleuridae Silurian Liten Formation, Czech Republic	Odontopleura ovata Family Odontopleuridae Silurian Liten Formation, Czech Republic	Selenopeltis buchii Family Odontopleuridae Ordovician Erfoud, Morocco	Acanthalomina minuta Family Odontopleuridae Silurian Kopaninske Formation, Czech Republic
Odontopleura markhami Family Odontopleuiridae Ordovician New South Wales, Australia	Kettneraspis williamsi Family Odontopleuridae Lower Devonian Haragan Formation Coal County, Oklahoma	Ceratonurus sp. Family Odontopleuridae Lower Devonian Haragan Formation Coal County, Oklahoma

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