Trilobites of the Steamboat Limestone


Northwestern Montana

Steamboat Limestone-on the crest of Prairie Reef - Deiss 1936



Elrathiella prima (formerly Coelaspis prima)
Elrathiella cliffensis
(formerly Glossocoryphus cliffensis)
Elrathiella typus
(formerly Glossocoryphus typus)
Glyphaspis dearbornensis
G. indenta
G. similis
Kochaspis dearbornensis
K. resseri
K. unzia
K. upis
Parehmania inornata
(formerly Mcnairia inornata)
Parehmania obscura
(formerly Thomsonaspis obscura)
Parehmania striata
(formerly Thomsonaspis striata)




Deiss,Charles (1939) Cambrian Stratigraphy and Trilobites of Northwestern Montana. The Geological Society of America, Special Papers, Number 18


Resser, C.E. (1935) Nomenclature of some Cambrian Trilobites, Smithsonian, Misc. Coll.., Vol. 93, No. 5, P. 1-46


*researched and compiled by George Ast and James Cook


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