Best Zone Fossil

Cambrian paradoxidid trilobite closely related to Paradoxides, known from Gondwanan terranes and used to trace dispersal of Cambrian pelagic faunas across paleocontinents.

Middle Cambrian trilobite whose species O. indicus defines a globally recognized biozone used to correlate Cambrian stratigraphy across multiple continents.

Arthricocephalus is a Cambrian trilobite genus from South China used as an index fossil for the lower Cambrian strata of that region.

Middle Cambrian corynexochid trilobite distributed across North America and Asia, commonly found in deposits contemporaneous with the Burgess Shale fauna.

Crepicephalus is a Late Cambrian trilobite genus from North America that serves as the namesake of the Crepicephalus Biozone used in Cambrian correlation.

Late Cambrian trilobite that defines the Cedaria biozone, a key division in Upper Cambrian stratigraphy widely used for correlation across North America.

Middle Cambrian trilobite widespread across North America, serving as a key index fossil for the Bathyuriscus-Elrathina biozone in Cambrian stratigraphy.

Middle Cambrian trilobite abundant in North America that gives its name to the Glossopleura biozone, a key interval in regional Cambrian stratigraphy.

Saukia is a Late Cambrian trilobite genus belonging to family Saukiidae, found in North America and Asia, and associated with the Sauk megasequence.

Elvinia is a Late Cambrian trilobite genus from North America used as an index fossil for the Elvinia Biozone in the upper Franconian Stage.

Ptychaspis is a Late Cambrian trilobite genus from North America whose name defines the Ptychaspid biomere, a key concept in Cambrian biostratigraphy.

Middle Cambrian marjumiid trilobite from North America whose fossils serve as index fauna for stratigraphic zones in the Basin and Range province.

Middle Cambrian marjumiid trilobite from North America, common in carbonate platform deposits of the western interior United States and used in biostratigraphy.

Cambrian trilobite from Siberia used as an index fossil for the Botomian Stage, aiding global correlation of Lower Cambrian strata across continents.

Irvingella is a Late Cambrian trilobite genus valued for intercontinental biostratigraphic correlation, with occurrences in North America, Europe, Asia, and Australia.

A Late Cambrian agnostid trilobite genus whose type species, Agnostotes orientalis, defines a key global biozone near the Cambrian–Ordovician boundary.

Late Cambrian trilobite widely used as a biostratigraphic index fossil for upper Cambrian zones, particularly in Scandinavia and Baltic paleocontinental regions.

Late Cambrian saukiid trilobite from North America, with early specimens described from New York State, used in Upper Cambrian biostratigraphic correlation.

Middle Cambrian trilobite of the order Corynexochida with broad distribution across North America, Europe, and Asia during the mid-Cambrian period.

Late Cambrian trilobite defining the Aphelaspis biozone, a key stratigraphic marker for the Steptoean Stage in the North American Cambrian time scale.

A Cambrian agnostid trilobite with worldwide distribution, serving as an important biostratigraphic index fossil for Middle to Late Cambrian correlations.

A Late Cambrian trilobite genus from North America, classified within the order Ptychopariida and known from Upper Cambrian deposits of the United States.

Dunderbergia is a Late Cambrian trilobite from the Great Basin of Nevada, USA, named after Dunderberg Peak in the Eureka District.

A cosmopolitan Cambrian agnostid trilobite, Cotalagnostus is recognized by its distinctive two-segmented pygidial axis and wide geographic distribution.

Late Cambrian trilobite closely related to Parabolina, known from Scandinavia and employed in upper Cambrian biostratigraphic correlation across the Baltic region.

Late Cambrian trilobite from North America of the family Pterocephaliidae, known for its broad pygidium bearing prominent marginal and pleural spines.

Middle Cambrian corynexochid trilobite found in North America and Asia, recognized by its distinctive elongated pygidium bearing marginal spines.

A Cambrian agnostid trilobite with a near-global distribution, widely used in biostratigraphic correlation of Middle Cambrian strata across multiple paleocontinents.

Cambrian trilobite known from deposits in Nevada and other western North American localities, contributing to reconstruction of Cambrian shelf faunas.