American Trilobites
Trilobites
 
American Trilobites

Also see:
The nine orders of Arthropod Class Trilobita
House Range
Trilobites of Canada

 

The American trilobites gallery is arranged first by geological time, oldest near the top:
Peachella brevasina
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.
Naraoia sp.
A so-called soft-bodied trilobite
Middle Cambrian
Marjum Formation, Millard County, Utah
Peachella brevasina (exceedingly rare)
Order Redlichiida Superfamily Olenelloidea
Late, Lower Cambrian
Cararra Formation, Nopah Range, Inyo County, California
Altiocculus
Altiocculus drumensis
Order Ptychopariida
Family Alokistocaridae
Middle Cambrian
Marjum Formation
Millard County, Utah
Coosella Type I
Order Ptychopariida
Family Crecicephalidae
Middle Cambrian
Weeks Formation
Millard County, Utah
Exceedingly Rare Gerospina schachti
Order Ptychopariida
Middle Cambrian
Weeks Formation
Millard County, Utah
Nevadia weeksi
Order Redlichiida
Family Nevadiidae
Lower Cambrian
Poleta Formation, Nevada
Tricrepicephalus coria
Glyphaspis capella
Superfamily Anomocaroidea Family Anomocarellidae
Middle Cambrian
Wolsey Formation, Montana
Kootenia species
(extremely rare)
Order Corynexochida
Family Dorypygidae
Middle Cambrian
Upper Wheeler Formation, Millard County, Utah
Olenoides nevadensis
(Rare)
Order Corynexochida
Family Dorypygidae
Late, Lower Cambrian
Marjam Formation
Milliard County, Utah
Tricrepicephalus coria
Order Ptychopariida
Family Tricrepicephalidae
Middle Cambrian
Weeks Formation
Millard County, Utah
Altiocculus harrisi
Olenellus chiefensis
Order Redlichiida
Family Olenellidae
Lower Cambrian
Pioche Shale, Lincoln County, Nevada
Utaspis marjumensis
Order Ptychopariida
Family Alokistocaridae
Middle Cambrian
Marjum Formation, Millard County, Utah
Menomonia sp.
Order Ptychopariida
Family Menomoniidae
Middle Cambrian
Weeks Shale, Millard County, Utah
Altiocculus harrisi,
(formerly: Alokistocare harrisi)
Order Ptychopariida
Family Alokistocaridae
Middle Cambrian
Wheeler Shale
Millard County, Utah
Dresbachia amata
Order Ptychopariida
Family Menomoniidae
Middle Cambrian
Weeks Formation
Millard County, Utah
Densonella semele
Order Ptychopariida
Family Menomoniidae
Middle Cambrian
Weeks Formation
Millard County, Utah
Bathyuriscus fimbriatus
Family Dolichometopidae
Middle Cambrian
Marjam Formation
Milliard County, Utah
Olenellus fowleri
Order Redlichiida
Family Olenellidae
Lower Cambrian
Pioche Shale, Lincoln County, Nevada
Ptychagnostus michaeli
Ptychagnostus michaeli
Order Agnostida
Family Ptychagnostidae

Middle Cambrian
Wheeler Shale
Millard County, Utah
Olenellus sp.
Order Redlichiida
Superfamily Olenelloidea
Lower Cambrian
Eager formation, B.C., Canada
Modocia weeksensis
Order Ptychopariida
Family: Marumiidae
Middle Cambrian
Marjum Formation, Millard County, Utah
Peronopsis segmenta
Order Agnostida
Family Peronopsidae

Middle Cambrian
Wheeler Shale
Millard County, Utah
Esmeraldina (Palmettaspis) sp.
Lower Cambrian
Esmeralda County, Nevada
Brachyaspidion sulcatum
Order Ptychopariida
Family Kingstoniidae
Middle Cambrian
Wheeler Shale
Millard County, Utah
Ptychagnostus richmondensis
Order Agnostida
Suborder Agnostina
Family Ptychagnostidae
Subfamily Ptychagnostinae
Middle Cambrian
Marjum Formation, Utah
Albertella cf longwelli
Order Corynexochida
Family Zacanthoididae
Middle Cambrian
Nye County, Nevada
Brachyaspidian sulcatum
Ptychagnostus atavus
Order Ptychopariida
Suborder Ptychopariina
Superfamily Ptychoparioidea
Family Kingstoniidae
Middle Cambrian
Wheeler Shale
Millard County, Utah
Elrathia marjumi
Order Ptychopariida
Suborder Ptychopariina
Superfamily Ptychoparioidea
Family: Marjumiidae
Middle Cambrian
Marjum Formation, Millard County, Utah
Ptychagnostus atavus
Order Agnostida
Family Ptychagnostidae
Subfamily Ptychagnostinae

Middle Cambrian
Wheeler Shale
Millard County, Utah
Modocia typicalis
Order Ptychopariida
Family: Ptychopariidae
Middle Cambrian
Marjum Formation, Millard County, Utah

Olenellus clarki
Order Redlichiida
Family Olenellidae
Subfamily Olenellinae
Lower Cambrian
Latham Shale, San Bernardino County, California

Cedaria minor
Order Ptychopariida
Family Cedariidae
Middle Cambrian
Weeler Shale, Millard County, Utah
Ptychagnostus akanthodes
Order Agnostida
Family Ptychagnostidae
Subfamily Ptychagnostinae
Middle Cambrian
Marjum Formation
Millard County, Utah
Olenellus gilberti
Order Redlichiida
Suborder Olenellina Superfamily Olenelloidea Family Olenellidae
Subfamily Olenellinae
Lower Cambrian
Pioche Shale, Lincoln County Nevada
Nephalicephalus beebei
Bathyuriscus
Glossopleura sp.
Order Corynexochida
Suborder Corynexochina
Superfamily Corynexochoidea
Family Dolichometopidae
Middle Cambrian
Chisholm Shale, Millard County, Utah
Nephalicephalus beebei
Order Ptychopariida
Family Marjumiidae
Middle Cambrian
Weeks Formation,
Millard County, Utah
Elrathia kingii
Order Ptychopariida
Family Marjumiidae
Middle Cambrian
Weeler Shale, Millard County, Utah
Bathyuriscus wasatchensis
Order Corynexochida
Family Dolichometopidae
Middle Cambrian
Spence Shale, Utah
Olenellus terminatus
Genevievella granulatus
Amecephalus piochensis Trilobite
Olenellus terminatus
Family Olenellidae Subfamily: Olenellinae
Lower Cambrian
Pioche Shale, Lincoln County, Nevada
Genevievella granulatus (rare)
(formerly: Democephalus granulatus)
Family: Llanoaspididae
Middle Cambrian
Wolsey Formation
Mntana
Amecephalus piochensis
Trilobite Order Ptychopariida
Family Alokistocaridae
Middle Cambrian
Chisholm Shale, Lincoln County, Nevada
Isoteloides flexus
Pseudocybele nasuta
Triarthrus
Ptyocephalus declivita
(extremely rare)
Order Asaphida
Superfamily Asaphoidea
Family Asaphidae
Ordovician
Wah Wah Formation
Millard County, Utah
Isoteloides flexus (rare)
Order Asaphida
Superfamily Asaphoidea Family Asaphidae
Ordovician
Fillmore Formation, Millard County, Utah
Pseudocybele nasuta
Order Phacopida
Suborder Cheirurina
Superfamily Pilekiidae
Family Pliomeridae
Ordovician
Fillmore Formation
Millard County, Utah
Triarthrus eatoni
with Soft Tissue Preservation
Order Ptychopariida
Family Olenidae
Lorraine Shale, Lewis County, New York
Paratrinucleus acervulosus
Order Asaphida
Family Trinucleidae
Upper Ordovician
Blacksburg, Virginia

Presbynileus ibexensis
Order Asaphida
Superfamily Asaphoidea
Family Asaphidae
Fillmore Formation, Millard County, Utah

Isotelus maximus
Order Asaphida
Superfamily Asaphoidea
Family Asaphidae
Subfamily Asaphinae
Upper Ordovician
Arnheim Formation
Highland County, Ohio
Flexicalymene retrorsa
Order Phacopida
Suborder Calymenina
Superfamily Calymenoidea
Family Calymenidae
Ordovician
Richmond Formation (Arnheim Member), Mount Orab, Ohio
Homotelus florencevillensis
Order Asaphida
Family Asaphidae
Subfamily: Isotelinae
Upper Ordovician
Clayton County, Iowa
Cryptolithus bellulus
Order Asaphida
Family Trinucleidae
Upper Ordovician
Swatara Gap
Pennsylvania
Bathyurellus teretus
Order Proetida
Superfamily Bathyuroidea
Family Bathyuridae
Lower Ordovician
Fillmore Formation
Millard County, Utah
Ptyocephalus yersini
Order Asaphida
Superfamily Asaphoidea
Family Asaphidae
Subfamily Ptyocephalinae
Ordovician
Fillmore Formation
Millard County, Utah
Pseudocybele lemurei
Pseudocybele lemurei
Order Phacopida
Family Pliomeridae

Ordovician
Fillmore Formation
Millard County, Utah
Flexicalymene meeki
Order Phacopida
Suborder: Calymenina
Superfamily: Calymenoidea
Family Calymenidae
Ordovician
Richmond Formation (Arnheim Member), Mount Orab, Ohio
Anataphrus (Vogdesia) vigilans
Order Asaphida
Family: Asaphidae
Subfamily: Isotelinae
Ordovician
Maquoketa Formation, Fayette County, Iowa
Carolinites sp. aff. C. genacinaca
(exceedingly rare)
Order Proetida
Ordovician
Fillmore Formation Pogonip Group
Millard county, Utah
Radnoria/Trilobite-1.htm
Arctinurus boltoni
Radnoria sp
Order Proetida
Family Brachymetopidae
Middle Silurian
Rochester Shale Formation
Middleport, New York
Arctinurus boltoni
Order Lichida
Superfamily Lichoidea
Family Lichidae
Subfamily Lichinae
Middle Silurian
Rochester Shale Formation
Middleport, New York
Dalmanites limulurus
Order Phacopida
Family Dalmanitidae
Middle Silurian
Rochester Shale Formation
Middleport, New York
Comptonaspis swallowi
Order Proetida
Superfamily Aulacopleuroidea
Family Aulacopleuriidae
Silurian
Waldron Shale, Indiana
Spathacalymene Trilobite
Spathacalymene nasuta
Order Phacopida
Superfamily Calymenoidea
Family Calymenidae
Silurian
Ripley County, Indiana
Dicranurus hamatus elegantus
Kettneraspis williamsi
Reedops deckeri
Dicranurus hamatus elegantus
Order Lichida
Superfamily Odontopleuroidea
Family Odontopleuridae
Lower Devonian
Haragan Formation
Coal County, Oklahoma
Kettneraspis williamsi
Order Lichida
Family Odontopleuridae
Lower Devonian
Haragan Formatio
n
Coal County, Oklahoma
Reedops deckeri
Order Phacopida
Suborder Phacopina Superfamily Phacopoidea Family Phacopidae
Lower Devonian
Haragan Formation
Coal County, Oklahoma
Huntonia lingulcifer
Order Phacopida
Suborder Phacopina Superfamily Dalmanitoidea Family Dalmanitidae
Lower Devonian
Haragan Formation
Coal County, Oklahoma
Viaphacops
Paciphacops campbelli
Viaphacops sp. aff. bombifrons
Order Phacopida
Suborder Phacopina Superfamily Phacopoidea Family Phacopidae
Lower Devonian
Bois d' Arc Formation
Coal County, Oklahoma
Cysphaspis carrolli
Order Proetida
Suborder Proetina Superfamily Aulacopleuroidea
Family Aulacopleuridae
Lower Devonian
Haragan Formatio
n
Coal County, Oklahoma
Paciphacops campbelli
Order Phacopida
Family Phacopidae
Lower Devonian
Haragan Formatio
n
Coal County, Oklahoma
Phacops rana milleri
Order Phacopida
Superorder Phacopina
Superfamily Phacopoidea
Family Phacopidae
Devonian
Silica Shale, Sylvania, Ohio
Paciphacops birdsongensis
Order Phacopida
Superorder Phacopina
Superfamily Phacopoidea
Family Phacopidae
Lower Devonian
Birdsong Formation, Benton County, Tennessee
Phacops (Eldredgeops) rana crassituberculata
Order Phacopida
Superorder Phacopina
Superfamily Phacopoidea
Family Phacopidae
Middle Devonian
Silica Shale Formation, Paulding, Ohio
Phacops rana norwoodensis
Order Phacopida
Superorder Phacopina
Superfamily Phacopoidea
Family Phacopidae
Devonian
Cedar Valley Formation, Johnson County, Iowa
Basidechenella rowi
Order Proetida
Superfamily Proetoidea Family Proetidae
Devonian
Hamilton Group, New York
Bellacartwrightia
Dipleura dekayi
Order Phacopida
Family Homalonotidae
Devonian
Panther Sandstone, New York
Bellacartwrightia whiteleyi
Order Phacopida
Family Acastidae
Middle Devonian
Hamburg Group, New York
Griffithides bufo
Order Proetida
Superfamily Proetoidea Family
Proetidae
Mississippian
Edwardsville Formation, Crawfordsville, Indiana
Breviphillipsia sampsoni
Order Proetida
Superfamily Proetoidea Family
Proetidae
Mississippian
Chouteau Formation
Saline County, Missouri
Comptonaspis swallowi
Order Proetida
Superfamily Proetoidea Family
Proetidae
Mississippian
Chouteau Formation
Saline County, Missouri